Phenotypic variability of autochthonous walnut (Juglansregia L) genotypes in northwestern Bosnia and Herzegovina

Abstract

IntroductionThe walnut is an important species of edible nuts. The Juglandaceae family consists of seven genera, comprising of about 60 monoecious species. Persian walnuts, known as common or the English walnut (Juglansregia L.), are the only species that are grown for their edible nuts. It is extensively grown for the high quality of its nuts and timbers (McGranahan and Leslie, 2012). Generally, today's European walnut production still depends on trees grown from seeds rather than clonal trees. The characteristics of such production are inequality in the quality of fruit and irregular yielding which result in decreasing of the supply of walnuts to markets. Genetic variability in walnut populations has been observed very high and exists in various parts of the world (Polat et al., 2015;Toprak, 2019). Morphological characters are considered to be an option for selection and classification of promising germplasm. Morphological variation in nut sizes, thickness of shell, kernel percentage and yield of kernels in walnut trees from various geographical areas have been reported (Okatan, 2018; Gundesli et al., 2019).According to Forde and McGranahan (1996), walnut breeding programs focused mostly on the selection of genotypes with commercially important traits, such as high percentage of kernel, late leafing and flowering, and lateral habits of fruiting. Germplasm diversity is usually estimated using morphological descriptors (Bernard et al., 2018). Until recently, phenotypic evaluation was the first step for classifying and describing the germplasm and selecting superior walnut genotypes. So far, a large amount of research has been carried out on the evaluation of genotypes of walnuts in many countries of the world (

Morphometric Traits and iPBS Based Molecular Characterizations of Walnut (Juglans regia L.) Genotypes

“…Principal components with a statistical signi cance, the rst three PCs, explained 54.77% of the total variance and indicated a high phenotypic diversity in agro-morphological characters for studied genotypes. Similar to our study, previous studies revealed a high phenotypic diversity in pomological characters of walnut genotypes (Khavidi et al, 2019;Farrokhı Toolır and Mozaffarı 2020;Skender et al, 2020).…”

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Morphological Characteristics of Grapevine Cultivars and Closed Contour Analysis with Elliptic Fourier Descriptors

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