Morphological variation among Persian walnut (Juglans regia) genotypes within the population and depending on climatic year

The main goals of this study were to compare walnut genotypes of spontaneous flora of Romania, based on main sources of phenotypic variability, using both univariate (ANOVA and Tukey tests) and multivariate (PCA) statistical approaches. Six main sources of phenotypic variability (nut length, nut diameter I, nut diameter II, nut weight, kernel weight, kernel ratio) were used for the study. Based on this analysis, the aim is to provide a recommendation for culture, and to find out which of the analyzed walnut genotypes have the optimal values for all the observed traits. The results of the study indicate that the conclusions based on the use of univariate and multivariate statistical methods can be used successfully in identifying genotypes with superior characteristics in genetic diversity assessment studies. Six walnut genotypes (B29, B40, B8, B5, B6, B11) were determined to possess optimal values for all six main sources of phenotypic variability. These results show large phenotypic diversity among the selected walnut genotypes.