Economic thresholds of Thrips palmi (Thysanoptera: Thripidae) for eggplants in a greenhouse
Thrips palmi Karny has recently been implicated in damage to eggplant fruits. This thrips causes cosmetic scars on and deforms fruits, thus lowering their market value. To investigate the relationship between the density of thrips and the resulting damage, experimental plots with initial release densities of 0, 20, 40, 70, and 100 adults thrips per plot were established under greenhouse conditions. Thrips density (for flower sampling = x1; for sticky trap = x2) was monitored using flower sampling and blue sticky trap counts, and was found to be directly related to the proportion of damaged-fruits (y) and the reduction in fruit yield: significant relationships were found for the flower samples (y = 1.2261x1 − 0.6232, r2 = 0.8582) and for the trap catches (y = 11.667 ln(x2) − 9.5, r2 = 0.8896). The proportion of damaged fruits that could be tolerated from an economic perspective, based on the cost of controlling the thrips population chemically and the market value of the fruit, was 6.67–11.76 %; this translated into economic thresholds of 1.05–1.5 adults and/or larvae of T. palmi per flower or 4.91–10.17 adults T. palmi per four-day sticky card count.
Commodity risk assessment of Momordica charantia fruits from Honduras
Abstract The European Commission requested the EFSA Panel on Plant Health to prepare and deliver risk assessments for commodities listed in Commission Implementing Regulation (EU) 2018/2019 as ‘High risk plants, plant products and other objects’. Momordica fruits originating from countries where Thrips palmi is known to occur qualify as high risk plants. This Scientific Opinion covers the introduction risk for T. palmi posed by fruits of Momordica charantia L. imported from Honduras, taking into account the available scientific information, including the technical information provided by the National Service of Agrifood Health and Safety (SENASA) of Honduras. The risk mitigation measures proposed in the technical dossier from Honduras were evaluated taking into account the possible limiting factors. An expert judgement is given on the likelihood of pest freedom taking into consideration the potential pest pressure in the field, the risk mitigation measures acting on the pest in the field and in the packinghouse, including uncertainties associated with the assessment. For T. palmi on M. charantia fruits from Honduras, an expert judgement is given on the likelihood of pest freedom following the evaluation of the risk mitigation measures acting on T. palmi, including any uncertainties. The Expert Knowledge Elicitation indicated, with 95% certainty that between 9,406 and 10,000 M. charantia fruits per 10,000 will be free from T. palmi.
Genetics of the phenotypic evolution in sheep: a molecular look at diversity-driving genes
Background After domestication, the evolution of phenotypically-varied sheep breeds has generated rich biodiversity. This wide phenotypic variation arises as a result of hidden genomic changes that range from a single nucleotide to several thousands of nucleotides. Thus, it is of interest and significance to reveal and understand the genomic changes underlying the phenotypic variation of sheep breeds in order to drive selection towards economically important traits. Review Various traits contribute to the emergence of variation in sheep phenotypic characteristics, including coat color, horns, tail, wool, ears, udder, vertebrae, among others. The genes that determine most of these phenotypic traits have been investigated, which has generated knowledge regarding the genetic determinism of several agriculturally-relevant traits in sheep. In this review, we discuss the genomic knowledge that has emerged in the past few decades regarding the phenotypic traits in sheep, and our ultimate aim is to encourage its practical application in sheep breeding. In addition, in order to expand the current understanding of the sheep genome, we shed light on research gaps that require further investigation. Conclusions Although significant research efforts have been conducted in the past few decades, several aspects of the sheep genome remain unexplored. For the full utilization of the current knowledge of the sheep genome, a wide practical application is still required in order to boost sheep productive performance and contribute to the generation of improved sheep breeds. The accumulated knowledge on the sheep genome will help advance and strengthen sheep breeding programs to face future challenges in the sector, such as climate change, global human population growth, and the increasing demand for products of animal origin.