Karyotype analysis of some Allium species in Iran

The karyotypes of ۱۰ species (۱۵ accessions) of Allium from Iran were investigated using the squash technique and ۱% (w/v) aceto-iron-hematoxylin stain. The basic chromosome number was x = ۸, and only in A. giganteum (۱) x = ۷. Karyotypes of ۱۴ taxa of Allium were diploid with ۲n = ۱۶; only A. macrochaetum was tetraploid with ۲n = ۳۲. Satellite chromosomes were seen in A. asarense. All karyotypes were symmetrical, consisting of metacentric and submetacentric chromosome pairs. Only A. caspium and A. stipitatum (۱) had subtelocentric chromosomes. Karyotype analysis according to Stebbins categories placed the studied taxa in symmetric classes of ۱A and ۲A, indicating a symmetric karyotype. The results of the analysis of variance showed significant differences for total chromosome length (TCL), mean chromosome length (CL), long arm length (LA), short arm length (SA) and intrachromosomal asymmetry index (A۱). The longest chromosome length was detected on A. asarense, A. elburzense, A. giganteum (۳), A. rotundum and A. stipitatum (۳) (۱۷.۹-۱۹.۷ μm), while A. ampeloperasum demonstrated the shortest value (۸.۲ μm). Results of cluster analysis based on chromosomal parameters classified the taxa into four groups using the unweighted pair group method with arithmetic mean (UPGMA). Using principal component analysis, the first three components determined ۹۷.۳% of the total variation. The grouping of the taxa based on the ۲-D scatter plot using the first two principal components, corresponding to the results of the karyotypic characteristics.

کلیدواژه ها:

Chromosome ، Cluster analysis ، Cytogenetic ، Karyology ، Principal component analysis