چكيده لاتين :
The comparison of different methods for estimating the genetic diversity could define their usefulness in plant breeding and conservation programs. In this study, a total of 5 seed morphological traits, and 4 highly polymorphic simple sequence repeat (SSR) loci were used to study the morphological and genetic diversity and differentiation among 600 seeds from 6 beech (Fagus orientalis Lipsky) populations (each population 100 seeds from 10 forked and unforked beech trees). The analysis of variance of the morphological data revealed significant differences among seeds of each trees for all measured traits. Principal Component Analysis (PCA) and UPGMA clustering of studied populations or stem form groups in each population did not show any clinal trends in variation of seed and nut traits. A highly non significant correlation coefficient (R2 = 0.002, P = 0.227) between morphology and geographical distance matrices was calculated by the marker systems using mantelʹs test. Nut and seed morphological traits suggest no ecotypes existence of F. orientalis along with Iranian beech forests. Genetic structures were studied based on the mean genetic distance between seeds of each tree. Population differentiation was moderate and differed significantly (Fst = 0.13-0.22) among forked and monopodial tree groups. A tendency of a strong family structure among seeds of forked and monopodial genotypes was obvious, indicating the observed phenotypic variation was at least partly caused by genetic factors. Besides, the correlation between morphology and geographical distance matrices was significant (R2 = 0.136, P = 0.04), indicating the existence of a relatively clinal trends in variation of microsatellite loci. Low correlation coefficients (R2 = 0.028, P = 0.140) between distance matrices of two marker systems shows contrary microsatellites, morphological traits are relatively less reliable and non-efficient for precise discrimination of closely related genotypes and analysis of their genetic relationships.
