To evaluate the viability of exoscopes in the context of neurosurgical education and compare the use of a 4k3D exoscope to a traditional operative microscope in the execution of a task of anatomic structure identification on a model of cranial approach.A cohort of volunteer residents performed a task of anatomical structure identification with both devices three times across an experimental period of 2 months. We timed the residents’ performances, and the times achieved were analyzed. The volunteers answered two questionnaires concerning their opinions of the two devices.Across tries, execution speed improved for the whole cohort. When using the exoscopes, residents were quicker to identify a single anatomical structure starting from outside the surgical field when deep structures were included in the pool. In all other settings, the two devices did not differ in a statistically significant manner. The volunteers described the exoscope as superior to the microscope in all the aspects the questionnaires inquired about, besides the depth of field perception, which was felt to be better with the microscope. Volunteers furthermore showed overwhelming support for training on different devices and with models of surgical approaches.The exoscope appeared to be non-inferior to the microscope in the execution of a task of timed identification of anatomical structures on a model of cranial approach carried out by our cohort of residents. In the questionnaires, the residents reported the exoscope to be superior to the microscope in eight of nine investigated domains. Further studies are needed to investigate the use of the exoscope in learning of microsurgical skills. Operative exoscopes (Exo) are a relatively novel class of devices for intraoperative visualization and magnification in Neurosurgery, consisting of an HD camera mounted to a support arm streaming images to a large screen. Multiple exoscope models are commercialized; the more advanced units are capable of producing 3D 4K images on large screens.Superior ergonomics to traditional operative microscopes (OM) is often cited as one of the major, if not the biggest, advantages of the exoscope .Abundant reports, albeit mostly based on surveys and opinions, can be found in the literature concerning the perceived educational value the use of the exoscope affords to trainees and expert surgeons alike , 3. WithFurthermore, conflicting data are reported concerning the learning curve of the exoscope across different settings, even in similar tasks , 8.Few studies have comparatively investigated the use of the exoscope by residents for training purposes. During the execution of 2D and 3D tasks, a study found the traditional operative microscope to be superior to both 2D and 3D exoscopes and 3D exoscopes to be marginally better than 2D versions .The aim of this work was to compare the learning curves of residents using an exoscope and an operative microscope to perform the same task, to investigate whether the new paradigm of exoscopic surgery could be suitable for a beginner, and to investigate how learning on the exoscope can be compared to that on the microscope.The primary objective of the study was to evaluate the use of an operative microscope  and a 3D exoscope  by a cohort of residents during identification of anatomical structures.In order to guarantee patient safety and repeatability, an anatomical model  was used. The model reproduced a pterional approach, chosen because of its ubiquity and reproducibility in neurosurgical practice.The primary objective of the study was to investigate if the improvement achieved by residents comfort.Secondary objective of the study was the investigation of the residents’ progress over time with the two devices, whether and how seniority and previous experience influenced the performance of the single residents.Finally, we sought to investigate how the study participants felt about the visualization devices and the use of anatomical models.The study was designed as a preclinical laboratory investigation with a group of volunteers using both instruments in an alternate fashion. All residents from University of Milano-Bicocca and University of Brescia Neurosurgery Residency programs who volunteered for the study were enrolled.Prior to the first experimental session, investigators randomly generated 51 lists of 6 anatomical structures represented in the model of pterional approach to be used for the study. A so-called “Standard series” was generated from a subset of structures in the anterior cranial fossa and perisellar region. The small number and accessibility of the structures included in this series made it comparatively easier. The Standard Series is reported in Fifty more series, numbered sequentially, were generated from a list including all the structures featured in the model. At the beginning of their first experimental session, each participant was randomly assigned of these series .Two questionnaires were furthermore designed, one to be completed after each experimental session and one after the last session , 3.Prior to the study, all participants received specific instructions concerning the aims and modality of the study and a brief lecture concerning the pterional approach and relevant topographic neuroanatomy. Furthermore, the participants were given pictures of the anatomical model . Before Multiple surgical instruments, including metal suction tubes, spatula, and tweezers, were provided, and the participants were free to choose which instruments to use. The surgical model was placed on a table, and the participants were sitting on a chair, set to a comfortable height by each participant prior to starting the task .At the beginning of the task, the visualization device was in the resting position pointing next to the operative field. The participants were required to use the visualization device to identify each structure sequentially, and identification was performed by touching each structure and giving voice confirmation.After each structure was identified correctly, the investigator named the subsequent structure in the series.On each experimental session, participants went through the Standard series and the Personal series they were assigned with each visualization device.The participants were not informed that the same two sets of structures  would be repeated each time. Across sessions, the order in which each participant used the devices were used was alternated to compensate for a possible warm-up effect.The task was timed, and the timer was started when the investigator named the first structure to be identified and stopped when the sixth and last structure in the series was identified. The interval to each structure was also measured. Times were recorded in seconds and rounded to the nearest whole . They were asked to complete a second questionnaire (Questionnaire 2) at the end of the study. The questionnaires were designed to gather information concerning the previous experience of the participants with the visualization device, their assessment concerning multiple domains of the visualization device, and their preferences and opinions.Questionnaire 1: Items 1 through 8 required the residents to score different aspects of the exoscope as compared to the microscope on a Likert-type scale of 1 (very inferior) to 10 (very superior). Higher scores underlie and perceived superiority of the exoscope. Item 9 investigated discomfort and optic strain when using the exoscope, a score between 1 (absent) and 10 (unbearable) was given by each participant.Items 10 and 11 inquired about the amount of the participant’s previous experience with both devices. Item 12 inquired about whether the resident had significant amounts (arbitrarily chose as 100 h) of videogaming experience see .Questionnaire 2: This questionnaire investigated multiple domains of participants’ opinion of the two visualization devices, their personal preference, and whether they found training similar to the experimental design useful , and level of self-reported experience was assessed by a general linear mixed model with a random intercept. Statistical analysis and graphics were carried out by Stata Software version 16.The distribution of the time to identify the first structure was described by mean and compared by a standard Between March and May 2022, 16 residents see  from thep: 0.552) on the first try. A statistically significant improvement in the speed with each device was observed on the second and third tries, on average at 12.4 s (p: 0.008) and 10.3 s (p: 0.0001), respectively, on the microscope, and 9.5 s (p: 0.0001) and 10.5 s (p: 0.004), respectively, with the exoscope. Improvement between the second and third tries approached statistical significance on the microscope (p: 0.056), while it was not on the exoscope (p: 0.455). The average time on the final try did not differ between the exoscope and the microscope .No statistical difference was thus observed in the average time necessary for identification of the first structure between the microscope (15.4 s) and the exoscope (14.3 s) (p: 0.014) on the second try to 18.875 s (p: 0.002) on the third try. Improvement between the second to the third try was not statistically significant (p: 0.52).The average time required for task performance diminished significantly across the experiment. With the microscope, it went from 27 to 20.563 s (p: 0.003) and 16.12 s, respectively. Again, improvement from the second to the third try failed to prove significant (p: 0.08).On the first try with the exoscope, the average time required was 26.06 s. This later improved  to 19.81 s  and the third tries .Participants averaged 20.983 s using the microscope and 14.375 s using the exoscope. While using the microscope, the residents improved their performance significantly on both the second ; on the third (time: 10.56 s), the change was not significant compared to the second (p: 0.087), but it was compared to the first (p: 0.003).Using the exoscope, the performance improvement in average time was not statistically significant on the second try at 12.75 s (p: 0.01) and third tries (p: 0.001) compared to the microscope.This was the only instance that demonstrated a significant difference between instruments: the exoscope fared significantly better on the first (p: 0.01) and not between the second and the third (p: 0.66).The average time needed for the completion of the task with the microscope was 36.03, 26.5, and 24.87 s on the first, second, and third executions, respectively, with a statistically significant improvement between the first and second execution (p: 0.006) but not between the second and third (p: 0.235).The improvement was observed also with the exoscope, with an average time on the first execution of 40.9 s, which later improved to 27.62 and then 21.87 s. The improvement proved significant between the first and second attempt (p: 0.27).The final times achieved with the exoscope and the microscope did not display statistically significant differences , B (10–49 surgeries), and C (more than 50 surgeries) based on their answer to Item 10 of Questionnaire 1 see . As resiThe recorded times across attempts and devices of the three groups are represented in p: 0.01) sessions and not between the second and third (p: 0.192).Group A achieved average times of 34.5, 21.0, and 15.50 s on the microscope, displaying a significant improvement between the first and second (p: 0.00) and not between the second and third (p: 0.75).On the exoscope, the results were similar: 37.5 s on the first try, 19.50 s on the second, and 17.75 s on the third try. Again, the improvement proved to be significant between the first and second attempt (p: 0.2 and p: 0.855).Average times for task completion with the microscope were 25.71, 20.71, and 21.43 s across the first, second, and third attempts by group B. The improvement failed to prove statistical significance across sessions (p > 0.0001).Average time was 23.57 s on the first session, 21.29 on the second, and 17 s on the third, when using the exoscope. The improvement proved to be significant only between the first and third sessions .Microscope times were 22.80, 20, and 18 s, respectively, across three attempts. Again, the improvement, while found, failed to cross the threshold to statistical significance (p: 0.27) and the second and last (p: 0.02), but it was between the first and third (p < 0.0001).The times recorded when the exoscope was used were 20 and 40 s, then 18.20 and 13.60 s respectively. The difference was not significant between the first and second attempt (p: 0.07).The average time on the last session was 18 s with the microscope and 13.6 s on the last session; the difference in results approached statistical significance (p: 0.116).On the first try with the microscope , the difference in times, while present, was not statistically significant, even when comparing group A and group C (p: 0.025), with more experienced residents faring significantly better, not between intermediate and experienced residents (p: 0.54).A different effect was observed only during exoscope use, when comparing group A and B .All of the residents reported having used the microscope more than the exoscope before this study (Item 2). Among the participants, 31.2% believed the experience acquired with one device would translate to the other (Item 3).Specific training prior to exoscope use was believed to be necessary by 37.5% of the participants (Item 4).If forced to adopt only one device, 75% would pick the exoscope (Item 5).The exoscope was considered to be more intuitive to start using by 75% of the respondents (Item 6).87% for the volunteers believed the exoscope will be adopted as the standard visualization device in the Operatory Room (OR) in the ftuture (Item 7).Residents were asked to report how useful they considered the activities carried out in this study to be for their own education concerning the use of different visualization devices (Item 8), the average score was 7.875 (median: 7.8), and concerning how useful they considered the activities carried out in this study to be for their own education fort their spatial orientation and anatomic understanding, the average score was 7.88 (median: 8) (Item 9).Training on anatomic models was strongly praised by residents, with an average score of 9.5 (median: 10) on a scale of 1–10 (Item 10).While extensive speculation exists concerning the educational value of the exoscope as compared to the operative microscope , evidencStandard and Personal series.In this study, as we expected, the participants’ performance, assessed as time required to carry out the task, improved over time, i.e., they became progressively more efficient in structure identification. This effect was observed with both the exoscope and the OM and both on the so-called When the participants were considered together, the times achieved across three sessions in both the identification of the first structure and structures 2–6 do not differ significantly based on the device in use: the improvement occurs thus in parallel between instruments according to the pooled performance of all residents in this study. The only exception is the identification of the first structure in the personal series: the time to identify the first structure starting from a resting position outside the field was significantly longer with the microscope than with the exoscope, likely an effect of the superior maneuverability of the latter. This effect was maintained over time.The improvement in the second to sixth structures’ identification was apparent with both instruments, generally more marked between the first and second attempt than between the second and the third. In the Special series, the more challenging of the two, the improvement was more marked with the exoscope.While this could be due to lower starting ability with the exoscope and, thus, bigger margins for improvement with the exoscope, the average times at the beginning of the experiment fail to demonstrate a significant difference, which contradicts this theory. Instead, we propose the effect is due to the exoscope being better suited for tasks involving rapid readjustment among different, somewhat distant, structures.Concerning the effects of previous experience, all the residents reported greater experience in using the microscope compared to the exoscope prior to this study , but this did not seem to contribute to any significant advantage in using the microscope compared to the exoscope when the whole group was considered.In the experience subgroup analysis, an effect of the previous amount of experience was observed but failed to prove statistically significant.Only the beginner group was able to achieve significant improvement over each try; both the intermediate and advanced group failed to do so. We believe this is a consequence of the more experienced groups having already achieved a good level of proficiency in the use of the microscope prior to enrollment in this study. Indeed, the performance of the latter groups is better than those of beginners when starting out.Unsurprisingly, greater microscopic surgery experience seems to correlate with better performances in this task, but less experienced residents were able to rapidly catch up to their colleagues, while margins for further optimization by experienced subjects seem slim.The beginner group fared significantly worse on the first try than both the intermediate and advanced groups.The performance of the beginner group markedly improved on the second try, achieving a time comparable to that of more experienced colleagues’ first try. The intermediate group, while improving across tries, failed to do so in a statistically significant manner from each to the next. The advanced group did not display significant improvement from the first to the second try and last try either.The data suggest that previous experience, even with the microscope, proves to be useful when starting to use the exoscope, but this effect again disappears rapidly .p: 0.07). A possible explanation in the exoscope is better suited for such a task than the microscope, possibly because identifying out of field structures requires only readjustment of the camera and not the user’s upper body, as does the microscope. Thus, the performance ceiling is higher with the exoscope than the microscope, but it is only accessible to relatively more experienced users.Results on the first try for the advanced group did not differ significantly between the exoscope and the microscope, but there was a trend toward a significant difference on the last try  enrolled, the chosen task, and the crossover design, with the possibility of skill improvement being carried over among instruments.Future perspectives in this topic concern investigation of the educational value for residents and junior surgeons in the learning of surgical skills.We evaluated the performance of a group of residents in various stages of their neurosurgical education in a task 3D HD exoscope. The exoscope appeared to perform better when used to identify deeper structures while starting from outside the surgical field; otherwise, neither device seemed to offer significant advantages compared to the other in the execution of the task when the whole group was considered.Interestingly, our population seemed more inclined toward the exoscope than the microscope and scored the exoscope higher in all domains but depth perception. Further studies are needed to clarify the role and possible advantages of the exoscope in residents’ education.


Melolontha melolontha is an agricultural pest in many European countries. Populations have a synchronized 3 or 4 years life cycle, leading to temporally isolated populations. Despite the economic importance and availability of comprehensive historical as well as current records on cockchafer occurrence, population genomic analyses of M. melolontha are missing. For example, the effects of geographic separation caused by the mountainous terrain of the Alps and of temporal isolation on the genomic structure of M. melolontha still remain unknown. To address this gap, we genotyped 475 M. melolontha adults collected during 3 years from 35 sites in a central Alpine region. Subsequent population structure analyses discriminated two main genetic clusters, i.e., the South Tyrol cluster including collections located southeast of the Alpine mountain range, and a northwestern alpine cluster with all the other collections, reflecting distinct evolutionary history and geographic barriers. The “passo di Resia” linking South and North Tyrol represented a regional contact zone of the two genetic clusters, highlighting genomic differentiation between the collections from the northern and southern regions. Although the collections from northwestern Italy were assigned to the northwestern alpine genetic cluster, they displayed evidence of admixture with the South Tyrolean genetic cluster, suggesting shared ancestry. A linear mixed model confirmed that both geographic distance and, to a lower extent, also temporal isolation had a significant effect on the genetic distance among M. melolontha populations. These effects may be attributed to limited dispersal capacity and reproductive isolation resulting from synchronized and non‐synchronized swarming flights, respectively. This study contributes to the understanding of the phylogeography of an organism that is recognized as an agricultural problem and provides significant information on the population genomics of insect species with prolonged temporally shifted and locally synchronized life cycles.The European cockchafer  Analyses were based on genome‐wide single nucleotide polymorphism (SNP) loci obtained from double‐digest Restriction site Associated DNA sequencing (ddRADseq).The aim of this study was to address the following three topics: (1) analysing the population structures of 22.1M. melolontha beetles were established from 35 infested sites, including 20 sites in Switzerland, 12 sites in Italy and three sites in Austria  and two 3 mm NucleoSpin® steel beads (Macherey & Nagel). DNA was extracted using the LGC sbeadex Plant Kit (LGC) automated with the KingFisher Sample Purification System (Thermo Fisher Scientific). DNA quality was assessed visually after electrophoresis in 1%‐agarose gels and quantified with PicoGreen® fluorescent nucleic acid stain (Invitrogen).From 2017 to 2019, collections of a Figure . The map2.2M. melolontha and M. hippocastani was documented at nine sampling sites . The ddRADseq libraries were prepared with 240 ng DNA per sample according to Westergaard et al. . Genomic2.4process_radtags component of STACKS 2.55 using default settings  and expected heterozygosity (He), which considers both monomorphic and polymorphic nucleotides for more robust estimation. For each collection, nine individuals were randomly selected to account for differences in sample size between collections. Estimates were extracted from the STACKS population summary statistics output run including individuals with 0% missing data. The R package VCFR 1.13.0 was used to import vcf files into R , employs sequential K‐means, and relies on the Bayesian information criterion (BIC) to infer genetic clusters  approach that is increasingly used in ecology  was similar to expected heterozygosity  at all 35 sites. Mean values of Ho and He were overall small and similar across collections, but mean Ho values were slightly lower in the 10 South Tyrolean collections . Highest levels of heterozygosity were detected in the two collections from the Aosta Valley, i.e., Ho, 1.6 × 10−4 and 1.7 × 10−4 , suggesting a high degree of genetic similarity.Observed heterozygosity  and a South Tyrolean (29: Plattl) collection, while the lowest genetic distance was found between two Swiss collections . A Mantel test performed between Nei's genetic distance and geographic distance matrices revealed a significant positive correlation  association between geographic and genetic distance. Temporal isolation exhibited a negative significant  association with genetic distance. In accordance with the model, genetic distance was slightly, but significantly higher between collections separated by a larger distance, and significantly, though slightly lower among collections from sites where adults were swarming in the same year  revealed that the model including both geographic distance and temporal isolation as explanatory variables was the most suitable; the DIC value of this model was lower than the values obtained for models including either none, only geographic distance or only temporal isolation as explanatory variables Table . The modr Figure .4M. melolontha in an Alpine region, which is particularly affected by severe crop and grassland damage caused during infestations  might represent separate genetic lineages, which recolonized the studied alpine region from different refugia. The collections from northwest Italy , although belonging to the northwestern alpine cluster, showed admixture with South Tyrolean genotypes at K = 2, whereas at K = 7, they showed membership coefficient to a separate cluster  showed shared ancestry at K = 7  in Switzerland, with some years having larger peaks . Since M. hippocastani, which is morphologically similar and has a life cycle of 4 years, is also documented in this region . Studies on the grasshopper Chorthippus parallelus, aimed at investigating the genomic differentiation of individuals in the same region of the “passo di Resia”, revealed levels of differentiation at the cytogenetic and genetic level between northern and southern collections along the pass. The authors hypothesized that this finding was the result of a postglacial expansion of C. parallelus from at least one Balkan refugium to the north of the Alps and from one refugium in southern Italy to the south of the Alps  was particularly interesting, because despite the geographic proximity of these collections, which is approximately 15 km, individuals were assigned to different STRUCTURE clusters Figures , 3b. Thes Figure . The altM. melolontha species in the Alpine region studied. An increase in genetic distance with increasing geographic distance has been observed , despite isolation by distance and the presence of regions of limited gene flow represented in Figure Ips typographus along a transect with a diameter of 300 km in Sweden , interbreeding is more likely between individuals from the same area and less frequently occurs between geographically distant individuals, implying that gene flow tends to be greater between geographically adjacent collections. However, the isolation by distance model is simplistic and other factors, e.g., phylogeography, landscape elements, temporal isolation and anthropogenic activities like pesticide use or agricultural intensification can influence population differentiation within species , located at 1074 m altitude, had a life cycle of 4 years . The Glurns collection area could thus have been colonized from sites with a 3 year life cycle at a lower altitude, and the movement of adults to higher altitudes with lower average temperatures might have decelerated the life cycle to 4 years. Faber . Reduced life cycle length will increase the frequency of years with serious crop damage and higher losses for farmers and fruit growers. Therefore, it is relevant to regularly monitor the life cycle length of M. melolontha, in order to define the most appropriate timing for treatment with B. brongniartii biological control products and to assess whether increased temperatures have an effect on the efficacy of these products and on the establishment of B. brongniartii in the soil. In addition, because increased temperatures may cause a change in the distribution range of M. melolontha and thus causing infestations to reach higher altitudes with less intensively used, high‐biodiversity grasslands, it will be important to monitor its occurrence in newly infested areas and survey potential further damage.According to the results of this study, temporal separation also had an effect, although small, on the genetic distance among collections. Temporally synchronized collections  were characterized by slightly smaller genetic distances between them, suggesting that the length and timing of the life cycle contributes to population differentiation Figure . Populats. Faber  already M. melolontha might cross the “passo di Resia”, a former landscape barrier. A change in the life cycle length of M. melolontha due to global warming, could synchronize previously temporally isolated populations from the south and north of the pass, and directly affect genetic distance between these populations, resulting in increased admixture and gene flow between separate lineages. Because of its sensitivity to temperature fluctuations, which may have direct consequences on the physiology of individuals, their life cycle, and, subsequently, also on the population genomic structure, M. melolontha has the potential to become a model insect for monitoring and studying the consequences of climate change in the Alpine region.It will be particularly interesting to monitor the development of the distribution range at the border between North and South Tyrol. With rising temperatures, M. melolontha in the central Alpine region with the existence of two main genetic clusters, i.e., a northwest alpine and a South Tyrol cluster, reflecting evolutionary history and geographic barriers. The “passo di Resia” connecting South and North Tyrol represented a regional contact zone of the two genetic clusters, with a marked genomic differentiation between the northwestern  and southern (South Tyrol cluster) collections. Although the two collections established from Aosta  were allocated to the northwest alpine genetic cluster, they showed signs of admixture with the South Tyrolean genetic cluster, indicating shared ancestry. Furthermore, the results showed (2) a significant positive correlation of geographical distance and genetic distance among collections of M. melolontha, possibly resulting from limited dispersal capacity. Finally, even though geographic distance was revealed as the main factor influencing genomic structure, the results of the present study also revealed (3) a distinct genetic distance based on temporal isolation (year of flight) of collections, likely as a consequence of reproductive isolation due to temporally synchronized and non‐synchronized swarming flights. This study not only yielded novel data on intraspecific genetic diversity of M. melolontha and its connectivity between natural populations, but also important information for current M. melolontha monitoring approaches.In conclusion, the results of this study revealed (1) population genomic structure of The authors declare no conflicts of interest.Data S1.Click here for additional data file.


Domestic duck populations in China have abundant genetic resources, and this study is the first to evaluate domestic and wild Mallard populations. To explore the genetic diversity and ancestry of duck populations, we analyzed a sequence (619–667 bp) of mitochondrial DNA (mtDNA) in the control region. Two Muscovy duck breeds were included in this analysis, along with wild Mallard ducks, Eastern spot-billed ducks, and 22 domestic duck breeds. Significant genetic diversity was found among domestic duck breeds. These results not only provide valuable insights into the genetic makeup of domestic ducks but also provide clues to the possible origin of domestic ducks in China.(Anas platyrhynchos) were detected in most of the Chinese domestic duck breeds. In addition, the Eastern spot-billed duck (A. zonorhyncha) H8 haplotype was detected in two duck breeds. Only two haplotypes were found in Muscovy ducks, suggesting low genetic diversity within this population. The sequence and haplotype analyses revealed that both A. platyrhynchos and A. zonorhyncha contributed to the evolution of domestic ducks in China.China has a rich genetic resource in its 34 domestic duck breeds. In order to detect the genetic diversity and explore the origin of these indigenous duck populations, the mitochondrial DNA (mtDNA) control region was sequenced and analyzed for 208 individual ducks, including 22 domestic breeds, wild Mallards ducks, Eastern spot-billed ducks, White Muscovy ducks, and Black Muscovy ducks. The haplotype diversity (Hd) was 0.653 and the average nucleotide diversity (Pi) was 0.005, indicating moderate genetic diversity. Sixty haplotypes were detected, and the maximum-likelihood (ML) phylogenetic tree and median-joining (MJ) network were generated from the sequence analyses. In this study, haplotypes from the Mallard duck  Anas platyrhynchos), the interbreeding of domesticated Mallard ducks and domesticated Eastern spot-billed ducks (A. zonorhyncha), or the domestication of wild hybrids of A. platyrhynchos and Anas zonorhyncha [A. platyrhynchos and A. zonorhyncha [A. platyrhynchos than for A. zonorhyncha [A. platyrhynchos [A. platyrhynchos and A. zonorhyncha. Waterfowl resources are rich in China, and the Genetic Resources Committee has officially recognized these resources ,2. Thereorhyncha . Previouorhyncha ,6,7. Usiorhyncha . He et aorhyncha . Similarrhynchos . OverallA. platyrhynchos [It was confirmed that the mitochondrial DNA (mtDNA) could more effectively evaluate the genetic diversity of poultry . Unlike rhynchos . HoweverA. platyrhynchos and A. zonorhyncha.This study performed the first comprehensive evaluation of domestic duck populations and wild Mallard ducks in China. We analyzed a 619–667 bp sequence of the control region of the mitochondrial DNA (mtDNA) of 22 domestic duck breeds, in addition to wild Mallard ducks, Eastern spot-billed ducks, and two Muscovy duck breeds. Sequence and haplotype analyses of the region revealed a high genetic diversity among the domestic duck breeds evaluated in this study. In addition, the identification of haplotypes shared across duck species suggested that Chinese domestic ducks originated from All animal experiments were performed in accordance with the Regulations for the Administration of Experimental Animals issued by the Ministry of Science and Technology . All experiments were approved by the Animal Care and Use Committee of Yangzhou University .n = 8) and the Black Muscovy duck (n = 8), were collected from Putian in Fujian Province and used as the reference group for the analysis. These blood samples (approximately 3 mL) were collected from the wing vein of the ducks in individual vacuum blood collection tubes. The genomic DNA was extracted using a genomic DNA extraction kit . RNA was purified to remove genomic DNA (gDNA), miRNA, and rRNA using the RNeasy Micro kit , RNase-Free DNase kit (Qiagen), and RiboZero™ MagneticKit , respectively. Data collection and analysis were conducted at the College of Animal Science and Technology, Yangzhou University, Yangzhou, Jiangsu Province, China.According to the pedigree records, 208 blood samples were collected from unrelated duck individuals . In addi2 (25 mM), 1.0 μL of dNTPs (10 mM), 1 μL of each primer (10 μM), 0.2 μL of Taq DNA polymerase (5 U/μL)  Co., Ltd.), 1.0 μL of DNA template (100 ng), and of 11.3 μL of sterilized water. The reaction was brought to a final volume of 20 μL by adding double-distilled autoclaved water. PCR amplification was carried out with an Eppendorf Mastercycler . The thermocycler was set as follows: 95 °C (5 min), 94 °C (45 s), 58 °C (45 s), 72 °C (45 s) for 35 cycles, and a final elongation step at 72 °C for 5 min. The last elongation step was extended to 8 min at 72 °C, and samples were held at 4 °C. The F-Primer and R-Primer were provided by Sangon Biotech Shanghai Co., Ltd. , for the direct bidirectional sequencing of target fragments within the PCR products using the ABI 3730 XL sequencing platform.The 667-bp  or 619-bp (Muscovy duck) segment of the mtDNA control region was PCR-amplified using the primers 5′-CCTATGGTCCCGGTAATAAACA-3′ (F-Primer) and 5′-GATAACGCAGGTGTGTCCAG-3′ (R-Primer), which were designed according to the Beijing duck sequence (accession number NC_009684) in GenBank . The PCRSequences of the mtDNA fragments were visualized by Chromas2 software and manually browsed to ensure the accuracy of the bases. Sequences were aligned by DNAStar-MegAlign V.7.10. The genetic diversity parameters of the populations, such as variable nucleotide sites, haplotype diversity, and nucleotide diversity, were calculated by DnaSP V.5.0 software ,17. The The data of 208 ducks were analyzed, and the average composition of the sequences was 25.01% A, 15.71% G, 34.23% C, and 25.05% T , showing little base bias. A total of 99 polymorphic sites (10 singleton variable sites and 89 parsimony-informative sites) were detected. As all insertions and deletions were removed from the analysis, the variable types were classified as transitions and transversions.A total of 60 haplotypes were identified among 26 duck breeds , includiThe average haplotype diversity (Hd), nucleotide difference (K), and nucleotide diversity (Pi) in these 26 duck populations were 0.653, 3.104, and 0.005, respectively; the Zhongshan duck (ZS) had the highest , while Sichuan Ma duck (SC) and White Muscovy duck (BF) had the lowest . A. platyrhynchos) and spot-billed ducks (A. zonorhyncha) in this study.The major H5 haplotype was shared by 61 ducks  from 18 domestic breeds and 3 wild Mallard ducks. The H8 haplotype was shared by one Mallard duck, one Zongyang duck, and one spot-billed duck . The ML A. platyrhynchos (Hd = 0.987 and Pi = 0.008 in Kulikova’s study) [Studies on the origin and evolution of livestock breeds through the different mtDNA sequences also contribute to the understanding of the domestication process of species . For thes study) . In comps study) ,28,29 ans study) , but it s study) . HaplotyStudies on the genetic diversity and genetic structure of species are important components of biodiversity conservation . PreviouA. platyrhynchos. The Eastern spot-billed ducks clustered into the H7–H10 haplotypes. Interestingly, the H8 haplotype was shared by one Mallard duck, one ZY duck, and one spot-billed duck, indicating that the partial domestic duck breeds in China might have originated from A. zonorhyncha. However, there were no other shared haplotypes between the domestic and spot-billed duck populations. Finally, our results suggested that domestic Chinese ducks evolved from A. platyrhynchos and A. zonorhyncha.However, there is still no consensus in the field regarding the origin of domestic ducks in China ,36. In tA. platyrhynchos and A. zonorhyncha contributed to the evolution of domestic ducks in China. The Sichuan Ma duck (SC) and White Muscovy duck (BF) had the lowest Hd, K, and Pi. To summarize, their conservation requires more attention and prioritization of conservation funds in the future.Sixty haplotypes were detected in most of the domestic Chinese duck breeds analyzed in this study. The sequence and haplotype analyses revealed that both


This study explored the molecular characterization of 14 eggplant  genotypes to evaluate their genetic diversity and the impact of heterosis. As eggplant is a vital horticultural crop with substantial economic and nutritional value, a comprehensive understanding of its genetic makeup and heterosis effects is essential for effective breeding strategies. Our aim was not only to dissect the genetic diversity among these genotypes but also to determine how genetic distance impacts heterotic patterns, which could ultimately help improve hybrid breeding programs.Genetic diversity was assessed using 20 SSR markers, and the parental lines were grouped into five clusters based on the Unweighted Pair Group Method of Arithmetic Means (UPGMA). Heterosis was examined through yield and yield-related traits among parents and hybrids.Polymorphisms were detected in eight out of the twenty SSR markers across the parental lines. Notably, a high genetic distance was observed between some parents. The analysis of yield and yield-related traits demonstrated significant heterosis over mid, superior, and standard parents, particularly in fruit yield per plant. Two crosses (RKML-26 X PPC and RKML1 X PPC) displayed substantial heterosis over mid and better parents, respectively. However, the positive correlation between genetic distance and heterosis was only up to a certain threshold; moderate genetic distance often resulted in higher heterosis compared to very high genetic distance.These findings emphasize the critical role of parental selection in hybrid breeding programs. The results contribute to the understanding of the relationship between genetic distance and heterosis, and it is suggested that future research should delve into the genetic mechanisms that drive heterosis and the effect of genetic distance variance on heterosis. The insights drawn from this study can be harnessed to enhance crop yield and economic value in breeding programs. The recent progress in genetic technologies has provided unparalleled prospects to enhance the genetic variability of eggplant. Marker-assisted selection (MAS) techniques have been developed to facilitate the identification, selection, and crossing of plants with desirable traits by breeders. These techniques have been found to be highly efficient in achieving this goal. The utilisation of these techniques may facilitate an increased comprehension of the eggplant’s genetic composition and expedite the breeding procedure to augment the crop’s efficacy and durability . The utiRecent technological advancements have facilitated a more in-depth exploration of the mechanisms that underlie heterosis, also known as hybrid vigor. This phenomenon is characterised by the superior traits exhibited by the first generation of hybrid offspring, surpassing those of the most proficient parent . The pheThe diversification of eggplant’s genetic composition is not solely a scientific pursuit, but also a crucial economic necessity. Eggplant, a vegetable with origins traced back to India, is a significant contributor to agricultural land usage and yield in the country. According to Solanum melongena. The utilisation of genetic technologies and a comprehensive comprehension of mechanisms such as heterosis can enable the exploitation of eggplant’s complete genetic diversity to the advantage of farmers, consumers, and the environment. Given the concurrent challenges of population expansion and climate change, the significance of this research cannot be overemphasized.Therefore, the presence of genetic diversity is an indispensable resource in our efforts to address the issue of food insecurity and enhance nutritional achievements. The utilisation of this technique enables the augmentation of the robustness, yield, and nourishing properties of significant cultivars such as Solanum melongena , with the ultimate goal of devising more accurate predictive models for heterosis effects in hybrid cultivars. The present study entails a comprehensive investigation of the copious genetic variability present in brinjal, specifically in India, which is one of its primary centres of origin. The objective is to harness this diversity for the amelioration of brinjal cultivars via heterosis breeding. The present investigation integrates the utilisation of molecular markers, particularly Simple Sequence Repeats (SSRs), to expedite a more efficient breeding methodology. The primary aim of this study is to utilise the obtained results to augment crop efficacy, amplify output, boost immunity against diseases, and thereby aid in worldwide efforts to tackle food scarcity by creating resilient, high-capacity eggplant varieties.The present investigation aims to elucidate the complex interplay between genetic similarity and hybrid vigor in In this study, the methodology was designed around three primary areas of focus: plant materials, morphological characterization, molecular characterization, and heterosis estimation.The investigation took place at the RKMVERI’s Ranchi research farm over three Rabi seasons . A total of 35 indigenous brinjal lines sourced from various locations in Jharkhand were used, alongside four high-yielding genotypes, selected as testers. These lines were carefully chosen from a core collection pool for their distinctive characteristics and their adherence to the DUS  standards as prescribed by the Authority for the Protection of Plant Varieties and Farmers’ Rights, under the Indian Ministry of Agriculture and Farmers Welfare. Post-classification and further evaluation, these lines are slated for registration .A Randomized Block Design was used to conduct the experiment thrice, considering 19 quantitative characteristics as outlined by DUS guidelines. Four-week-old seedlings were transplanted into the main field with a spacing of 75 X 50 cm. Each plot comprised 20 plants across a 9 m2 area, and five randomly chosen plants from each plot were assessed for all quantitative traits across all replications. Exceptions were the days to flower initiation, days to 50% flowering, and days to fruit initiation, which were monitored at the plot level. The mean of each trait was computed over the three replications, and a Euclidean dissimilarity matrix was generated using these traits. Accessions were then clustered using Ward’s method, facilitated by the R ‘cluster’ package.The genetic diversity of ten indigenous brinjal lines and four testers were evaluated using 20 SSR (Simple Sequence Repeats) markers . DNA wasThe assessment of heterosis, also known as hybrid vigor, is a crucial aspect in augmenting agricultural productivity and acclimatising to alterations in the environment . The curThis is calculated by comparing the performance of the hybrid to the average performance of its parents.1 represents the value of the trait in the hybrid, and MP represents the average value of the trait in the parents.Here, FThis is calculated by comparing the performance of the hybrid to the performance of the better-performing parent.1 is the value of the trait in the hybrid, and BP is the value of the trait in the better-performing parent.Here, FThis is calculated by comparing the performance of the hybrid to a standard cultivar or check variety.1 represents the value of the trait in the hybrid, and ‘check’ represents the value of the trait in the standard cultivar. These formulas allow the heterosis for a specific trait to be expressed as a percentage, which can be helpful in comparing the degree of heterosis across different hybrids or different traits.Here, FTen indigenous brinjal lines were selected from a pool of 35 lines sourced from different locations in Jharkhand, based on their cluster affiliations. The chosen lines were found to be representative of all four clusters, namely RKML1 for Cluster 1, RKML 2, 3, 6 & 26 for Cluster 2, RKML4, 7, 11 & 34 for Cluster 3, and RKML 5 for Cluster 4. This selection was made to ensure a diverse genetic foundation for the study. In accordance with the study conducted by earlier workers , four unA series of crosses were performed between ten genetically distinct lines and four tester lines. In order to achieve a bountiful and thriving harvest, customary cultural procedures were executed in accordance with the guidelines established by Birsa Agricultural University (BAU), a well-established methodology for enhancing agricultural output .The present investigation concerns a heterosis study, wherein multiple quantitative traits were assessed on a sample of five arbitrarily chosen plants in every treatment. The study encompassed an analysis of various traits, namely the number of primary branches, leaf length, leaf width, petiole length, fruit length, fruit diameter, number of fruits per plant, number of marketable fruits per plant, single fruit weight, seeds per fruit, yield per plant, marketable yield per plant, and total yield per hectare. The assessment of traits is a crucial aspect in the identification of exceptional hybrids within plant breeding initiatives .Phenological traits, including the duration of time until the initiation of flowering, the duration of time until 50% of flowering, and the duration of time until the initiation of fruiting, were observed and documented on a complete plot level. The prompt and accurate observation of these traits is of utmost importance as they have a direct impact on the crop’s productivity and adaptability to particular cultivation conditions .The present study aimed to estimate heterosis and assess the potential of selected brinjal lines crossed with specific testers for further use in breeding programmes, by analysing hybrid vigor. The aforementioned endeavours were aimed at providing insights into methodologies for enhancing the quality of brinjal crops, thereby aiding in the resolution of the worldwide issue of insufficient food supply, as emphasised by the International Treaty on Plant Genetic Resources for Food and Agriculture .D2 statistic, indicating significant divergence among the lines  were chosen for the purpose of hybridization. The genotypes in Clusters III and V were both comprised of seven members. Four genotypes, namely RKML-7, 4, 11, and 34, were identified as potential candidates for further crossing from cluster III. Cluster I comprised six distinct genotypes, and the RKML-1 genotype was selected as the representative line for this cluster. Cluster IV comprised of four distinct genotypes, among which the RKML-5 line was chosen for the purpose of crossing. The present study reports the identification of three genotypes, namely Pusa Purple Cluster, Pusa Purple Long, and S. Pratibha, which were classified under Cluster VI. These genotypes were utilised as testers during the hybridization process. One of the testers from Cluster II, S. Shyamli, was chosen for the hybridization process. The selected lines and testers were sourced from separate clusters, indicating a significant divergence among the parental lines. This is a critical factor for future crossbreeding initiatives.Distinct trait combinations were observed in each cluster. Cluster III, comprising of RKML-4, 7, 11, and 34, exhibited the most elevated cluster mean for nine distinct traits. On the other hand, Cluster IV, consisting of RKML-5, demonstrated the highest cluster mean for five distinct characteristics. In addition, the genotypes encompassed in this cluster exhibited the least amount of time required to attain 50% flowering and fruit initiation. The results of the study indicate that Cluster I exhibited the greatest seed count per fruit, whereas Cluster II  exhibited the shortest duration to flowering. Cluster V was observed to display the maximum count of fruits per plant, thereby indicating a superior level of productivity. The aforementioned observations provide evidence for the existence of significant genetic variation among the chosen parental strains, which is a crucial factor in achieving successful heterosis breeding.A molecular characterization study was conducted on 14 genotypes to assess the genetic diversity among the parental lines. A total of twenty markers were employed in the study, revealing the presence of polymorphisms in eight of the 14 parental lines, thereby indicating the existence of genetic diversity  and marketable yield (66.86%) over the superior parent.Considerable positive heterobeltiosis was observed in three hybrids with respect to yield per plant, and in two hybrids for marketable yield per plant. The hybridization of RKML-1 and PPL resulted in the manifestation of the highest heterotic value, which was recorded at 42.40% and 39.91%. The present study investigated the total yield of the hybrid RKML1 X PPC and observed a significant positive heterosis of 98.25% over the mid-parent and 97.54% over the superior parent. In this study, a total of twenty hybrids were analysed for their trait expression and exhibited a notable degree of heterosis over the mid-parent. Additionally, fifteen of the hybrids displayed a statistically significant increase in positive heterobeltiosis. The present study reports the significant standard heterosis of twelve hybrids, among which the hybrid RKML-26 X PPC exhibited the highest degree of 108.67%. The results of this study suggest that there is a significant level of exploitable heterosis in brinjal. This highlights the potential of utilising heterosis breeding techniques to enhance the yield and other related traits in brinjal cultivars.While previous studies suggest that hybrid performance isn’t solely dependent on genetic distance, the relationship between heterosis and genetic distance is valid up to a specific threshold of genetic divergence . HeterosIn this study, as presented in Positive correlations  were estimated between genetic distance and better parent and standard heterosis, considering only the significant cases. These results indicate that when striving for normal heterosis, it may be beneficial to select hybrids that produce superior hybrids.When comparing the yield assessment of hybrids with the genetic distance grouping of parent plants, it was observed that hybrids derived from crosses between parents with the highest genetic distance exhibited a higher degree of heterosis than those resulting from crosses between parents with the least genetic distance. This relationship further reinforces the importance of considering genetic distance in the pursuit of maximizing heterosis and yield potential in brinjal cultivation.The crop of aubergine, which is highly variable in India, presents a multitude of landraces and commercial cultivars that showcase diverse morphological traits, specifically in relation to fruit characteristics . The preThe study conducted by The molecular characterization of high-quality germplasm is an essential aspect of formulating breeding tactics and recognising exceptional complementary lineages. The utilisation of molecular markers, such as Simple Sequence Repeats (SSRs), for the purpose of genetic diversity analysis has been deemed a cost-effective approach. This is due to the high variability, enhanced genome coverage, repeatability, automation potential, neutrality, and immunity to environmental disturbances that SSRs offer . The preThe phenomenon of heterosis is characterised by the enhanced performance of hybrid progeny in multiple domains, including but not limited to yield, adaptability, resistance to pests and diseases, overall robustness, and quality. The present investigation evaluated the performance of hybrid RKML1 X PPC. Results showed that this hybrid manifested the most noteworthy positive effect over the mid-parent and better parent. Approximately 50% of the crosses displayed considerable heterosis over the mid-parent, while 37% exhibited significant heterobeltosis in a positive direction. These findings were reported by The comprehension of the correlation between genetic diversity and heterosis is of great significance for the advancement of inbred lines and plant breeding, with the aim of enhancing the efficacy of germplasm utilisation . Several1 hybrid vigor being our primary approach for generating heterosis. Therefore, Simple Sequence Repeats (SSRs) present an advantageous method for identifying parental components contributing to heterotic effects due to their high polymorphism, which allows differentiation even among closely related individuals. The study provided compelling evidence that economically superior hybrids are typically a product of more genetically distinct parents. However, in the case of brinjal, a remarkable observation was that hybrids derived from crossings between parents with moderate genetic distance exhibited more heterosis than those resulting from parents with a very high genetic distance. These findings suggest that genetic distance can serve as a reliable predictor of heterosis in parents, but only up to a certain threshold. As we look towards the future, a key area of focus should be a deeper exploration of the relationship between genetic distance and heterosis. Additionally, understanding the precise genetic mechanisms and factors driving heterosis could lead to more predictive and strategic hybrid breeding programs. Furthermore, studying the interplay of genetic diversity with environmental factors may offer insights into how to increase crop yield stability under variable conditions. Lastly, advancing molecular marker technology, such as SSRs, and integrating it with advanced genomic and bioinformatic tools could provide a more nuanced understanding of the heterotic effect, eventually leading to more effective and efficient strategies for crop improvement.Our understanding of heterosis and its underlying mechanisms remains limited, with the exploitation of FThe original contributions presented in the study are included in the article/SD and NR: conceptualization, data curation, investigation, supervision, and manuscript writing and editing. KP, FK, BP, AS, MK VS, VK, PJP and ML: data analysis, investigation, manuscript writing and editing. All authors contributed to the article and approved the submitted version.


Phenotypic variability within and between populations can be assessed using morphometric traits. Therefore, this study investigated morphological differences between different goat populations in two distinct agroecological zones of Burkina Faso. Based on 18 linear body measurements and body weight of the 511 adult female animals sampled, no strict distinction was found between the two populations, meaning that these populations are genetically close. Based on body size, four groups were identified representing the two main breeds expected in these areas , their crosses, and the crossbred between Mossi type and the third main breed (Sahelian type) of the country. These different goat morphotypes are the results of farmers breeding practices, specifically uncontrolled mating but also intentional crossbreeding in the search for traits of interest.p < 0.001) larger body measurements than Sudanian goats. Furthermore, relative high variability of the two populations in morphometric traits was observed. Principal Component Analysis (PCA) suggested structure between Mossi breed on one side and Djallonké on the other side, but no strict separation was observed, suggesting that gene flow is occurring among the different populations. A dispersion map with four clusters was built based on the first two factors. The least square means of body measurements ranked the four groups from small to large body size, namely Djallonké, Mossi × Djallonké, Mossi, and Sahelian × Mossi. Gene flow from Sahelian goat into other populations of the country, based on migration of the Fulani ethnic group from the Sahel into areas with Mossi and Djallonké breeds, could explain this configuration and confirms the continuous erosion of genetic identity of these two local breeds. The sustainable use of these adapted local goat genetic resources calls for the promotion of sustainable genetic improvement using participatory breeding approaches.In Burkina Faso, goats are the second most numerous ruminant livestock population, with almost exclusively indigenous breeds being reared in extensive production systems in various agroecological zones. This study was carried out to understand the morphological variation of local goat breeds in the Sudano-Sahelian and Sudanian agroecological zones. A total of 511 adult female animals belonging to two presumed populations  were sampled and body weight as well as a range of linear body measurements, following FAO guidelines, were recorded. The least squares means of body measurements of indicated that Sudano-Sahelian goats have significantly ( In Burkina Faso, goats are the second largest ruminant population. They are exclusively indigenous breeds reared in extensive production systems in various agroecological zones. Indeed, with nearly 15.5 million animals, goats represent about 43% of the domestic ruminants herd, putting Burkina Faso among the countries hosting an important population of this species with a particular socioeconomic importance ,3,4,5,6.Three main goat breeds are traditionally recognized in Burkina Faso based on ethnic and/or geographic location nomenclatures. The Sahelian breed, characterized by a large and elongated body with long and thin limbs, is distributed throughout the Northern region. The Djallonké breed, located in Southern Burkina Faso (Sudanian area), is a short-eared, small-horned goat belonging to the West African dwarf goat population. In the Sudan-Sahel area of the country, there is an intermediate breed between the two previous, named the Mossi breed ,8,9. BurThe characterization of African small ruminant populations will play a major role in the maintenance of these autochthonous genetic resources as the basis for future improvement at both the production and the genetic levels . This chTherefore, the aim of this study is to contribute to the genetic characterization of native goats by investigating their morphological differences in different agroecological zones of Burkina Faso. The results of this study may be useful and important for future breeding programs and management plans of these local breeds.The study was carried out in two provinces, Namentenga and Poni , correspA total of 511 female goats with a minimum age of 3 years in five sites were sampled in the two provinces. The number of animals sampled per site is reported in During the process of data collection, animals were assigned based on their phenotypic appearance to genotypes corresponding to the local breeds of the country named Djallonké, Mossi, Sahelian, and their crosses by the research team. This assignment has been done based on the experience of the team from previous studies.The data was registered directly on the Online Data Kit (ODK)/KoboToolbox platform, then exported to Excel and transferred to R software  for statp < 0.001) variations among the two zones for all linear body measurements. The highest mean values of body weight and most of the linear body measurements were observed in the Sudano-Sahelian area. The coefficient of variability (CV) indicated that variability ranged from 6.31% (height at rump) to 27.48% (chest width) in the whole population. Globally, CV values were relatively low for most of the traits except for body weight (BW), ischium width (IW), tail length (TL), and Muzzle circumference (MC), which were 18.63%, 14.87%, 12.02%, and 27.48%, respectively.Morphometric traits variation among the two agroecological zones are presented in Relationships between traits were analyzed by constructing bidimensional dispersion plots. The first two components of the PCA plot accounted for 85.4% of the total variability of the data . Eight tp < 0.001) higher than those generated by permutation, confirming the validity of our clusters. According to the least squares means of the seven linear body measurements and body weight used for the clustering, the four groups can be arranged from small to large body size (p < 0.05) different for all these linear body measurements and body weight.The results of the ascending hierarchical classification optimized by the determination of the possible number of groups (K) suggested that the optimal number of groups was four . The aveody size  and assiA comparison of assignments by hierarchical classification and subjective evaluation of animals provided extremely high concordance. Indeed, the assignment was 100%, 96.27%, and 88.93% true for Djallonké × Mossi, Mossi, and Djallonké, respectively . HoweverMorphological measurements are a useful tool to describe variability within and between populations. Therefore, they have been used for the characterization of many livestock populations worldwide ,27,28,29The findings of this study suggest notable variation in the physical characteristics of goats in Burkina Faso. Overall, the goats in the two agroecological zones showed high variability in morphometric traits. Globally, Sudano-Sahelian population showed large body proportions compared to goats in Sudanian zone, suggesting distinct ancestry of goats in the two areas. This trend corroborates the findings of previous similar studies of goats in Burkina Faso and in Benin ,30,31. CPrincipal Component Analysis (PCA) suggested structure between Mossi and Djallonké goats and the lack of strict separation, suggesting that genes flow is potentially occurring between the two agroecological zones and specifically from the Sudano-Sahelian into the Sudanian populations. High gene flow in livestock populations in West Africa has been suggested to be a consequence of several factors including mobility and breeding practices. The high phenotypic variation observed in this study would be linked to the action of nomadic Fulani people who move with their Sahelian breeds from the north into the south in search of pasture, causing crossbreeding with native Sudanian types due to uncontrolled mating . In addiIn this study, four morphotypes were found and are probably the consequence of this introgression. Furthermore, the means values of eight variables (seven linear body measurements and body weight) of the discriminant analysis revealed morphological differences among the two agroecological zones. Ranking from the tallest to the smallest, we identified Sahelian × Mossi crossed, Mossi from the Sudano-Sahelian zone, Sahelian × Djallonké crossed, and Djallonké from the Sudanian zone. The variation from large to small body size observed from the Sudano-Sahelian to Sudanian zone confirms the findings of previous studies supporting that goats body size tends to decrease following the geographical gradient north–south ,26,31,34This study showed a weak differentiation between the different genotypes with two intermediate subgroups appearing between the two well-identified breeds . Animals from Mossi type and crossbreeds formed various overlapping clusters indicating low genetic differentiation. The Djallonké tend to form their group with, however, a few Mossi individuals. Genetic group assignment by hierarchical clustering based on weight and linear body measurements coincided very well with subjective breed assignment of a livestock expert, except for crossbred Sahelian × Mossi. This is consistent with the findings of previous similar studies ,9, claimGenes flowing from Sahelian goats into other populations of the country could explain this configuration and confirms the continuous erosion of genetic inheritance of Mossi and Djallonké breeds. Sustainable genetic improvement programs including reasonable crossbreeding need to be promoted to help farmers to meet their needs while preserving the genetic integrity of these indigenous goat breeds. Thus, different breeding programs could be suggested, including pure breeding and crossbreeding programs. To be sustainable, such breeding programs should be implemented with full participation of farmers, taking into account their preferences in animal traits and their breeding practices. Community-based breeding programs that encourage farmer participation is most likely to be fit within such a context ,37.The objective of this study was to assess phenotypic variability of local goat populations in two agroecological zones of Burkina Faso. The results showed that globally the Sudano-Sahelian population have larger body measurements than the Sudanian goat. Out of 19 morphometric traits, 8 linear body measurements and live body weight allowed the clustering of the two populations in four morphotypes, including the native Mossi breed in the Sudano-Sahelian area and the Djallonké breed in the Sudanian zone, while two hybrid groups emerged and were assigned to Djallonké × Mossi and Sahelian × Mossi crossbreds, respectively. Variation in body size was observed among these four subpopulations going from large body size in the Sudano-Sahelian morphotypes to small body size in the Sudanian ones. Several factors could explain this configuration and the variation of body size observed in these goat populations in the study areas, including adaptation and breeding practices (crossbreeding). To prevent the potential genetic erosion caused by this practice, managed breeding programs should be promoted, including supervised crossbreeding systems. Participatory breeding approach like community-based breeding programs can be suggested. In addition, the use of morphological measurements is a basis of genetic characterization of livestock populations, but this approach has some limitations because it does not provide enough information on genetic diversity or on the performance of animals in specific traits. Regarding this, our study should be completed by genomic studies using molecular markers to provide a deep understanding of the genetic makeup of goats populations in the areas.


Osteonecrosis of the femoral head (ONFH) is a disabling and intractable orthopedic disease largely affecting young and middle-aged groups. Current standard of treatment relies on the collapse of femoral head as a predictor for prognosis. However, a wide range of variability in repair potentials is observed in patients with femoral head collapse. Therefore, the present study aimed to evaluate the accuracy of femoral head collapse as a predictor and to propose the necrotic lesion boundary as a novel yet reliable measure for ONFH prognosis.A retrospective cross-sectional study was conducted at the First Affiliated Hospital of Guangzhou University of Chinese Medicine, 203 hips with ONFH from 134 patients were included. The occurrences and progression of femoral head collapse were recorded. Necrosis lesion boundary was quantified and classified for each case based on anteroposterior view intact ratio (APIR) and the frog-leg view intact ratio (FLIR) as independent variables. Dependent variables were defined as progressive collapse or terminal collapse for Association Research Circulation Osseous (ARCO) stage II and III respectively. Logistic regression analysis, Receiver Operating Characteristic (ROC) curve and Kaplan-Meier (K-M) survival analysis was performed and results were interpreted.Out of the 106 hips in ARCO stage II, 31 hips collapsed with further progression, while 75 hips had no collapse or collapse with repair of the necrotic areas. Out of the 97 hips in ARCO stage IIIA, the collapse continued to progress in 58 hips while the necrotic areas were repaired in 39 hips. Logistic regression analysis demonstrated that both APIR and FLIR, were independent risk factors. Further ROC curve analysis indicated that the cutoff values of APIR and FLIR could be considered as indications for evaluating the prognosis of ONFH. Contrary to the traditional view of poor prognosis after femoral head collapse, K-M survival analysis demonstrated a high value of APIR and FLIR for ONFH prognosis.The present study found that the occurrence of collapse is an oversimplified predictor for ONFH prognosis. The collapse of the femoral head in ONFH does not predict a poor prognosis. The necrosis lesion boundary has a high value in predicting ONFH prognosis and informing clinical treatment strategies. Osteonecrosis of the femoral head (ONFH) is a disabling and intractable orthopedic disease largely affecting young and middle-aged groups . ONFH isIn current clinical practice, femoral head collapse is a marker of severe irreversible osteonecrosis and is an indication for hip preservation surgery or total hip arthroplasty (THA) –21. HoweSince we observed a high correlation between the anterolateral necrotic boundary and the collapse of femoral head , we hypoThis study was approved by the institutional review board. Patients with ONFH who presented to the First Affiliated Hospital of Guangzhou University of Chinese Medicine from January 2000 to December 2016 were included. The diagnosis of ONFH was confirmed by senior doctors from X-ray and MRI based on the Chinese Guideline for the Diagnosis and Treatment of Osteonecrosis of the Femoral Head in Adults .Inclusion criteria were as follows: (i) patients who presented with ARCO stage II or IIIA (based on ARCO classification standard established in 2019); (ii) patients aged between 18 years and 55 years; (iii) patients with regular follow-up and complete imaging data of hip X-rays taken at least once every 6 months. Both anteroposterior (AP) view and frog-leg lateral (FL) view of both hips are required.Exclusion criteria were as follows: (i) patients who underwent hip preservation surgery during the follow-up; (ii) patients with severe cardiovascular and cerebrovascular diseases, tumors, infections, or mental health deficit; (iii) patients who had coxa plana, congenital hip dysplasia or other diseases that affect the normal physiological structure of the hip joint; (iv) patients who had rheumatoid arthritis, ankylosing spondylitis and other rheumatic diseases involving the hip joint; and (v) patients who continued to take glucocorticoids or drink alcohol.The anteroposterior view intact ratio (APIR) and the frog-leg view intact ratio (FLIR) were used to assess the retention of the anterolateral boundary of the necrotic lesion. The necrosis lesion boundary was quantified by APIR and FLIR Figure 1Our study reclassified ONFH by quantitative values of the necrosis lesion boundary. According to the proportion of the non-necrotic area of the weight-bearing part of the femoral head in the weight-bearing area of the acetabulum corresponding to the AP view, the lateral necrotic boundary is classified ((i) For ARCO stage II, progressive collapse as an endpoint was defined as persistent collapse without repair (collapse >4 mm or progression to ARCO stage IV) at follow-ups; and(ii) For ARCO stage IIIA, terminal collapse as an endpoint was defined as persistent collapse without repair (collapse >4 mm or progression to ARCO stage IV) on X-rays. The degree of collapse was measured according to Nishii’s modified method .According to the severity of femoral head collapses, patients in ARCO stage II were separated into a progressive collapse group and non-progressive collapse group (non-progressive collapse group included patients with no collapse). Patients in ARCO stage IIIA were separated into a terminal collapse group and a necrotic repair group based on the repair progress of the femoral head.All analyses of data were conducted with SPSS Software version 23.0  and GraphPad Prism Software version 7.04 . Measurement data were tested for normality using the Kolmogorov-Smirnov method. Measurement data subject to normal distribution were expressed as mean ± standard deviation (Mean ± SD), and independent samples t-test was performed, and variables that did not obey normal distribution were expressed as median and interquartile range [M ]. The independent samples t test was used to compare the measurement data that obeyed the normal distribution between groups, and the nonparametric two independent sample Mann-Whitney U test was used for the non-normal distribution. The count data were expressed as frequency and analyzed by chi-square test. Univariate and multivariate logistic regression analysis were performed to identify the risk coefficient of the variable, and then the receiver operating characteristic (ROC) curve was used to evaluate the cutoff of the variable. The Kaplan-Meier (K-M) survival analysis was performed with the classification of outcomes. All statistical analyses were two-sided, with p-values < 0.05 indicating statistical significance.A total of 203 hips from 134 patients were included in this study, including 106 hips in ARCO stage II and 97 hips in ARCO stage IIIA. According to the necrosis lesion boundary classification, there were 3 type A hips, 21 type B hips, 133 type C hips, 26 type D hips, 20 type E hips, 1 type a hip, 28 type b hips, 128 type c hips, 28 type d hips and 18 type e hips. 113 hips were diagnosed with steroid-induced ONFH (SONFH), 70 hips with alcohol-associated ONFH (AONFH), and 20 hips with idiopathic ONFH (IONFH).Out of the 106 hips in ARCO stage II, 31 hips collapsed with further progression while 75 hips had no collapse or collapse with repair of the necrotic areas. Out of the 97 hips in ARCO stage IIIA, the collapse continued to progress in 58 hips while the necrotic areas were gradually repaired in 39 hips. For both ARCO stage II and IIIA, the necrotic lesion boundary classification turned out to be a key factor affecting the outcome in both the progressive collapse and terminal collapse groups P=0.000, Table 1.The combined intact ratio (CIR) was an ROC model for the joint diagnosis of APIR and FLIR. For the progressive collapse group, ROC curve analysis showed the cutoff value of 19.83%  for APIR, the cutoff value of 17.63% for FLIR , CIR , had a higher diagnostic value for collapse  and Magnetic Resonance Imaging (MRI) can provide higher-resolution images, x-rays are currently still the most frequently used clinical examination imaging modality in China due to their low cost beneficial for the large population base. X-rays also have the ability to clearly show the anatomical relationships between bones, making them the best tools for identifying the boundary of necrotic lesions. Several studies have confirmed the value of an FL view on top of a traditional AP view of the X-rays for a clear evaluation of the anterior necrotic lesions , 12, 35.Current commonly used staging such as Ficat staging, Steinberg staging and ARCO staging only reflect the progression of ONFH (whether there is collapse or arthritis) compared to the necrosis lesion boundary classification, while ignoring the location of the necrotic lesion which is considered to be predictive of prognosis. In addition, although the Japanese Investigation Committee (JIC) classification is widely accepted across the world, it is limited in its ability to predict the prognosis of ONFH since it is based solely on the AP view and ignores the three-dimensional anatomy of the femoral head. In general, compared to other classifications, the necrosis lesion boundary classification is a more appropriate new classification to determine the prognosis of ONFH.This study has several limitations. First, the necrosis lesion boundary classification cannot be evaluated for ARCO stage I. Second, this classification does not take into account the size of the necrotic areas, which could potentially affect prognosis. Finally, the sample size of this study is relatively small, and real-life situations may have more complicated considerations. However, these limitations do not obscure the strengths of this study. The patients with non-progressive collapse group and necrotic repair group included in this study were followed up for at least 5 years, maximizing the accuracy of outcome determination. In addition, the necrotic lesion boundary classification is a novel classification that quantify lesion boundary based on both AP and FL views of x-raysTaken together, the occurrence of collapse is an oversimplified predictor for ONFH prognosis. The present study demonstrates that the necrosis lesion boundary has a high value to predict ONFH prognosis and to inform clinical treatment options.The raw data supporting the conclusions of this article will be made available by the authors, without undue reservation.This study was approved by the institutional review board of the First Affiliated Hospital of Guangzhou University of Chinese Medicine (No. JY [2021]165). The patients/participants provided their written informed consent to participate in this study.Conceptualization: YF and ZC. Data extraction and quality assessment: YZ and XL. Software: YF and YL. Formal analysis: JZ and HF. Validation: CZ, WH and ZC. Writing: YF and CZ. All authors contributed to the article and approved the submitted version.


Based on 22 qualitative traits, 13 quantitative traits, and 27 molecular markers (26 SSR and 1 InDel), in the current study we compared the diversity and population structure of 94 local landraces and 85 current breeding lines of pepper in China. The results showed that the Shannon Diversity indices of 9 qualitative traits and 8 quantitative traits in current breeding lines were greater than those of landraces, of which 11 were fruit organ-related traits. Compared with current breeding lines, the mean values of Gene Diversity index and Polymorphism Information content of local landraces were higher by 0.08 and 0.09, respectively. Population structure and phylogenetic tree analysis showed that the 179 germplasm resources could be divided into two taxa, dominated by local landraces and current breeding lines, respectively. The above results indicated that the diversity of quantitative traits of current breeding lines were higher than that of local landraces, especially traits related to fruit organs, but the genetic diversity based on molecular markers was lower than that of local landraces. Therefore, in the future breeding process, we should not only focus on the selection of target traits, but also strengthen the background selection based on molecular markers. Moreover, the genetic information of other domesticated species and wild species will be transferred to the breeding lines through interspecific crosses to expand the genetic background of the breeding material. Capsicum spp.) is an important vegetable crop and condiment widely grown in tropical and subtropical regions of the world. The genus Capsicum has 5 cultivated species, C. annuum, C. frutescens, C. baccatum, C. chinense and C. pubescens, and 33 wild species1, while its genome size ranges from 3.3 to 3.6 GB, the most complex and largest genome in the Solanaceae family3.Pepper 8. Using molecular markers such as Amplified Fragment Length Polymorphism (AFLP), Simple Sequence Repeats (SSR) and Single Nucleotide Polymorphism (SNP), the genetic diversity and population structure of large-scale germplasm materials were analyzed, and some core germplasm banks were constructed to further understand the genetic diversity of germplasm materials12. Numerous studies on the genetic diversity and structure of China's pepper germplasm resources, including those for particular regions15, specific uses or fruit shape of chili germplasm resources19, pepper germplasm resources introduced from abroad22, and core germplasm for breeding materials23 have also been published.Pepper germplasm resources showed huge differences at the phenotypic, biochemical and DNA levels, leading to high genetic diversity in the germplasm resourcesZun Sheng Ba Jian" in 1591. Due to the differences in ecological conditions and dietary habits of various regions of China, a large number of local varieties of pepper have been formed in the long-term natural selection and artificial improvement process24. In China, from 1965 to 1985, research was carried out on the collection, identification and preservation of pepper germplasm resources. At present, more than 2000 pepper germplasm resources are available in the National Genebank of China, which mostly consists of local landraces and also includes a small number of foreign commercial varieties25.Pepper was introduced to China in the late sixteenth century, and the earliest record was found in Gao Lian’s "C. annuum species, with a small amount of C. chinense. In 1972, breeders produced the first hybrid pepper variety26. Since then, Chinese breeders have developed a wide range of current breeding lines and hybrid varieties using classical breeding techniques like hybridization and backcrossing along with modern breeding technologies like molecular marker-assisted selection28. With the innovation of pepper breeding technologies, the development and promotion of pepper varieties has progressed a lot30. Pepper varieties have been improved for three to four generations in China. Currently, hybrids account for more than 95% of the total pepper production32. In the 1970s, our team at the Institute of Vegetable Crops, Jiangsu Academy of Agricultural Sciences bred the first hybrid variety of pepper 'Zaofeng No.1' in China by using the local landrace 'Nanjing Zao Jiao' and the foreign introduced germplasm 'German'. Since then, we obtained a large number of advanced generation inbred lines through genetic improvement of the progeny of local landraces and domestic and foreign commercial varieties. Over the past 50 years, we have bred the 'Su Jiao' series of varieties, which have been widely promoted and utilized in Jiangsu, Shandong, Anhui, Guangdong and other significant pepper production areas, directly reflecting the development trend of pepper breeding in China.The pepper varieties in China are dominated by 33. For the research reported herein, we evaluated the genetic diversity of 94 local landraces and 85 current breeding lines based on their phenotypic and molecular marker polymorphism in order to explore the changes in genetic diversity of pepper breeding resources after 40 years of artificial improvement and selection. This study will serve as a useful reference for guiding the future improvement of pepper breeding lines and the breeding of new varieties.Breeders generally agree that the genetic diversity of current pepper breeding lines is decreasing, but the exact situation is unclear. The reason is that there are few comparative studies of genetic diversity between current breeding lines and former local landraces. In this study, 179 materials were selected as research materials, including 94 local landraces and 85 current breeding lines. The 179 materials were primary core germplasm collections that we identified by evaluating 26 SSR markers and 1 InDel marker on 697 accessions, including 334 local landraces and 363 current breeding lines (data unpublished). The 334 local landraces were introduced from the National Genebank of China and originated from different regions of China in the 1980s, which were highly representative of varieties and breeding lines used 40 years ago in China. The 363 current breeding lines were improved and purified by our team in the recent five years. Among them, some current breeding lines mainly came from the improvement and selection of local landraces, while other current breeding lines came from the isolation and purification of commercial varieties from various regions of China. Therefore, the current breeding lines basically represent the main types of breeding materials for the market of China in recent years. Based on 35 phenotypic traits, the 179 accessions in the core germplasm collections represented about 70% of the genetic information present in the 697 accessions evaluated initiallyIn the previous study, a core collection of 179 materials according to SSR analysis was established based on 334 local landraces and 363 current breeding lines (data unpublished). The local landraces were collected in different regions of China before 1985, almost 40 years ago. In contrast, the current breeding lines are 8–10 generation inbred lines that were used for commercial breeding in the last 5 years. A small percentage of current breeding lines were improved based on local landraces and most of them were purified and improved based on market varieties. The core collection of 179 materials were used in the study, including 94 local landraces and 85 current breeding lines. The 94 local landraces, of which 85 accessions originated from 26 provinces or regions in China, and the remaining 9 accessions were introduced from abroad . The quality and concentration of DNA was measured by 1% agarose gel electrophoresis and Nano Drop One . The DNA concentrations were adjusted to 50 ng/μL and kept at − 20 °C in a refrigerator.35. Each SSR and InDel forward primer was labeled with one of four fluorescent dyes: 6-carboxy-fluorescein, 6-carboxy-tetramethylrhodamine, hexachloro-6-carboxy-fluorescein, or carboxy-X-rhodamine. All primers were synthesized by Tsingke Biotechnology Company .For SSR analysis, we used 26 microsatellite markers publicly available from Nicola et al. and 1 InDel from Guo et al. that spanned 12 pepper chromosomes−1), double distilled H2O 3.5 μL and approximately 1 μL of genomic DNA (50 ng/μL) as templates. Thermocycling was started at 98 °C for 3 min and followed by 30 cycles of 98 °C for 20 s, 55 °C for 10 s and 72 °C for 20 s, with a final extension at 72 °C for 5 min. Following the reaction, 2 μL of PCR product was taken for electrophoretic detection, and then the PCR product was diluted to 2 ng/μL. 10 μL of liz500 mixture (liz500:HiDi = 1:130) were added to each PCR product, which was then heated at 95 °C for 5 min and then cooled in ice water. Fluorescence detection was carried out on an ABI 3730 genetic analyzer .PCR was performed in 10 μL reaction volumes containing PrimeSTAR Max Premix (2 ×) 5 μL , 0.25 μL of each primer  and standard deviation (S) of the aggregate data. A score of 1 was given to any value less than M − 2S and a score of 10 was assigned to any value greater than or equal to M + 2S. Intermediate scores were based on increments of 0.5 S. Distribution frequencies were obtained from these scores. Shannon indices (H′) were also calculated from the scores , as was coefficient of variation 36 and were used to construct a phylogenetic tree based on the unweighted pair-group method of mathematical averages (UPGMA 5.10 Software) as implemented in MEGA  software.GeneMapper 4.0 software was used to evaluate the sizes of amplified fragments  from different samples. The number of unique alleles, gene diversity index, heterozygosity, and polymorphism information content (PIC) were calculated using Power Marker v3.25 software. Genetic distances were calculated by the method of Cavalli-Sforza and Edwards (1967)C. annuum accessions from China, we used the model-based program STRUCTURE v2.3.4. The optimal number of genetic groups (K) were computed by performing eight Markov chain Monte Carlo runs for each value of K from 1 to 10. Each run consisted of 100,000 iterations, with a burn-in period of 30,000 iterations, and used an admixture model allowing for Hardy–Weinberg equilibrium, correlated allele frequencies, and independent loci. A Pr(X|K) index with respect to each K was used to calculate ΔK  where X denotes the genotypes of the sampled individuals37. According to this approach, the optimal K is estimated as the location of the first peak of A ΔK =|L2(K)|/s[Pr(x|k)], where |L2(K)| denotes the absolute value of the second order rate of change of Pr(X|K), and s[Pr(x|k)] is the standard deviation of the Pr(X-|K), and s indicates standard deviation of L(K). The principal coordinate analysis (PCA) was performed with DARwin 5.0.158 Software.To infer the population structure of the 179 All plant experiments were carried out in accordance to relevant institutional, national, and international guidelines and legislation.Twenty-two qualitative traits of 94 landraces and 85 current breeding lines were investigated, and the total number of variation types were 86, with a very rich variation in fruit morphology Table . The ShaThere were six qualitative traits related to plant morphology, including plant habit, main stem color, stem pubescence, leaf shape, leaf color and leaf pubescence Table . The ShaFive qualitative traits related to flowers, including peduncle attitude, corolla color, anther color, stigma color and stigma exertion were also examined Table . The ShaA total of 11 qualitative traits were related to the fruits, among which the fruit shape had the highest number (9) of variation types Table . The ShaFor the other seven fruit related traits, the Shannon Diversity index differences between two populations was not significant, but there were certain regularities in the frequency distribution of variation types Table . In termThirteen quantitative traits of 94 landraces and 85 current breeding lines were investigated. The Shannon Diversity indices for the 13 quantitative traits in the 94 local landraces ranged from 0.98 to 2.17, with a mean value of 1.73, while the Shannon Diversity indices for these 13 quantitative traits of the 85 current breeding lines ranged from 1.70 to 2.04, with a mean value of 1.90. Overall, the Shannon Diversity indices of the current breeding lines were higher than those of the local landraces  and Polymorphism Information content (PIC) ranged from 0.16 to 0.88 and 0.14 to 0.87, with an average value of 0.56 and 0.53, respectively. Among these markers, the GDI and PIC of marker Epms331 were the highest, which were 0.88 and 0.87, respectively. The GDI and PIC of marker Epms391 was the lowest, which were 0.16 and 0.14, respectively , and 15 landraces 21.5%). The Pop2 group was predominated by landraces, with 79 local landraces (72.5%), and 30 current breeding lines, (27.5%). The number of lines with Q values greater than 0.6 in Pop1 and Pop 2 were 62 and 95, accounting for 88.6% and 87.2%, respectively, and 8 and 14 lines with Q values less than 0.6, respectively. The above results indicated that most of the Pop1 and Pop2 lines had a separate sources of genetic components, but some lines combined genetic components from both sources. There was some genetic information shared between the groups. The results for all 179 pepper lines were subjected to principal coordinate analysis, which supported the classification of the two groups, and some lines shared genetic components for both sources  cluster tree was constructed. The results showed that the 179 lines could be divided into two clusters. Cluster I included 85 lines, including 54 current breeding lines and 31 local landraces, accounting for 63.53% and 36.47%, respectively. Cluster II included 94 lines, including 63 local landraces and 31 current breeding lines, accounting for 67.02% and 32.98%, respectively. In the clustering process, some lines with similar agronomic traits were clustered together, such as B227, B247, B262, and B282were all long lantern-shaped, thin-flesh and mildly spicy peppers, while B305, GW090, GW143, GW221, GW160, and GW225 were all long lantern-shaped and thick-flesh sweet peppers. Meanwhile, the ox-horn-shaped and goat-horn-shaped lines, which accounted for a high proportion, also had similar preferential clustering. However, some lines of different fruit shape were clustered together, probably because some of the current breeding lines were obtained by purification after crossing of different fruit shapes  and fruit spiciness Table . All theor Table , indicator Table , 3. ThisAnalysis of 22 qualitative traits in 94 local landraces and 85 current breeding lines revealed significant differences in Shannon Diversity indices of eight qualitative traits between the two populations. In comparison with local landraces, the Shannon Diversity indices of four qualitative traits, including leaf pubescence, corolla color, fruit shape, and fruit glossiness in current breeding lines were lower. While the Shannon Diversity indices for leaf shape, stigma color, fruit shape of apex, and fruit navel appendages were higher in current breeding lines  with GDI and PIC of 0.36 and 0.29, respectively39. Genetic diversity analysis of a 200-member core collection using 61 SSR markers showed the mean values of GDI and PIC were 0.40 and 0.35, respectively23. The above results indicated that the diversity of pepper accessions of China was lower compared with accessions from some other countries, and artificial selection has led to a further reduction in the genetic diversity of breeding lines.While using the same SSR molecular markers as used in this study, the germplasm resources used in the previous studies were more numerous and more broadly sourced compared to those used in the present study, so the GDI and PIC values were higher in those studies compared to those reported herein. For example, Nicola et al. analyzed 1352 pepper accessions using 28 SSR markers, and the mean values of the GDI and PIC were 0.70 and 0.67, respectively12. Cheng et al. used 5149 SNP markers to classify 398 local landraces and backbone lines into two different taxa39. Meanwhile, phylogenetic tree analysis in this study showed that the clustering results based on genetic distance were correlated with fruit shape, and germplasms of the same fruit shape were more likely to be clustered together. This result was consistent with several previous reports23.The population genetic structure analysis and principal coordinate analysis indicated that there were relatively significant differences of the genetic backgrounds between the 94 local landraces and 85 current breeding lines, but some lines in the two populations likely shared genetic backgrounds. More similar to the results of the present study, Gu et al. clustered 1904 germplasm resources of China into two major taxa by population structure analysis and principal coordinate analysisSupplementary Figure 1.Supplementary Figure 2.Supplementary Table 1.Supplementary Table 2.Supplementary Legends.