Morphological characteristics of chestnut Castanea sativa from the area of Una-Sana Canton
Una-Sana Canton (USC) has a large forest areas where chestnut Castanea sativa Mill. grows as a self-sprout tree. The aim of this paper was to determine the morphological characteristics of chestnut fruits from four self-sprout locations (Bužim, Bosanska Krupa, Cazin and Velika Kladusa), and plantation where the domestic tree is grafted with Italian Marroni. Number of fruits/kg, the useless fruit, the percentage of kernel, diameter, width, height and weight of fruits were determined. The number of fruit/kg ranged from 160-222.5, percentage of useless fruit varied between 0.88-6.7%. Percentage of kernel ranged from 78.5 to 87.3%. According to the diameter classification, width, height and weight of fruits, chestnuts fruit from USC enters the category of the smallest fruits of the Mediterranean area. Statistical significant differences (p≤0.01) in the number of fruits/kg and weight of fruits was found between locations, as well in the width of the fruit (p≤0.05), while there is no difference in the diameter and height of the fruit. For grafted chestnut, all the characteristics provided better quality.
Usefulness of 13 morphological and phenological characteristics of sweet chestnut (Castanea sativa Mill.) for use in the DUS test
The descriptive value of 13 chestnut characteristics was assessed in the present study. The variables were measured over a period of 3 years in a contemporary collection of traditional cultivars located in two different environments in the northwest of the Iberian Peninsula. Descriptors, which are particular to each species, are used in the characterization, differentiation and protection of cultivars and should comply with the following three criteria: distinctness, uniformity and stability (DUS). Evaluation of the morphological and phenological characters was carried out with some UPOV descriptors and other descriptors previously recommended on the basis of their potential usefulness for the DUS test. ANOVA models were used to estimate the genetic and environmental components of variability and the genotype × environment interaction, with the aim of determining the properties of different descriptors for use in the DUS test. Most of the variables differed significantly among the cultivars, with high to very high heritabilities of between 0.63 and 0.97. Exceptions were observed with the variables fruit size, chestnut length and time of fruit ripening, which did not differ among cultivars in either plantation. The variables that showed the highest degree of distinctness, uniformity and stability were: time of leaf bud burst, filament length in male flower, time of beginning of male and female flowering, size of fruit hilum, and percentage of chestnuts with split pericarp. In contrast, time of fruit ripening, fruit size and chestnut length showed a low degree or no distinctness and highly heterogeneous degrees of uniformity and stability.
Estimating chilling duration from daily temperature extremes and elevation in Isreal
Deciduous plants require chilling temperatures in winter in order to complete the rest phase of dormancy and to enable normal renewed growth. Models were developed from limited Israeli records of hourly temperatures for estimating chilling temperatures at more widely available stations recording maximum and minimum temperatures. Models and maps were created not only for the traditional definition of chilling temperatures, I.e. hours below 7.2OC, but also for hours below 8.4 "C and 10.4 "C. These data will be useful for both operational care and planning future plantings of deciduous crops.