گزارش جديد كروموزومي و مطالعه كاريوتيپي چهار گونه گون astragalus در ايران

NEW CHROMOSOME NUMBER AND KARYOTYPE ANALYSIS IN FOUR ASTRAGALUS L. (FABACEAE) SPECIES

Karyotype studies were performed in four Astragalus species of A. cornu-carpoe, A. mucronifolius, A. tatimansurensis frum the section Leucocersis and A. crysostachvs from the section Hymenostegis . AU four species showed 2n = 2x :=: 16 chromosome number and had metacentric and sub-metacentric chromosomes. The size of chromosomes varied from 0.75 /lIn in A. tolimansurensis to 4.00 urn in A. cornu-carpae, The species studied differed significantly in the size of their chromosomes and in karyotype formulae indicating the role of quantitative change in the chromatin (DNA) material as well as chromosomes structural changes in the species diversification. The chromosome numbers of all four species studied are new to science. PCA ordination of the species showed their karyotype distinctness and that such data are of no use in the sectional delimitation in Astragalus,