مطالعه کاریولوژیکی ژنوتیپهای چای (.Camellia Sinensis L) موجود در ایران

Tea (camellia sinensis l.) is an important beveragecrops containing caffeine worldwide. releasingcultivars with high yield and quality demandsknowledge about tea genetics and cytogenetics.karyotypical study of nine tea genotypes was carriedout using squash method on root tips. the bestmicroscopic slides was first obtained using root tip oftea cuttings pretreated by ?-bromo naphthaline for 8 h,fixed by farmer solution and then stained withhematoxilin. eight morphological traits were taken intoconsideration, each within three meiotic chromosomesusing micromeasure software. analysis of varianceshowed significant differences (1%) among genotypes,chromosomes and the interactions, for all of themeasured parameters. all studied teas were diploid andhad 2n=2x=30 metacenteric and submetacentericchromosomes. total length of chromosomes rangedfrom 1.10 to 4.42 ?m. also, in terms of total length ofchromosomes, genotypes 4 and 8 had the highestcorrelation and genotypes 2 and 9 had the lowest.moreover some cytogenetic statistics was used in orderestimate the karyotypic symmetry of genotypes. theresults obtained showed that the genotypes 1 and 2 hadthe most asymmetric and genotypes 3 and 8 had themost symmetric, based on the tf%. ordination basedon principal components analysis (pca) revealedpresented that more than 97% of total diversity with two components was described. centromeric index andlong arm length had the most roles in the components,respectively. cluster analysis using upgma method,also grouped the genotypes in four clusters and 100promising clones were separated from the others,similar to result of pca bi-plot, relatively