Cytological Studies on Some Ecotypes of Nigella sativa L. in Iran

The karyotype of six Iranian ecotypes of Nigella sativa, which is a member of the Ranunculaceae family, was studied. The results showed that all studied ecotypes contained 12 chromosomes (2n=2x=12). The karyotype formulas for the ecotypes are: G1 : 5m+1T, G2: 4m+1sm+1st, G3: 5m+1st, G4: 5m+1T, G5: 4m+1sm+1T and G6: 3m+2st+1sm. The total form percentages (TF%) of the ecotypes observed were as follows: G1 40.64, G2 41.04, G3 43.83, G4 41.36, G5 39.60, G6 38.94. The largest total haploid length was detected in G6 (51.76 mu m) while G4 demonstrated the least (32.56 mu m). The first two principal component analysis (PCA) justified over 89% of the total variations of cytological characteristics. UPGMA cluster analysis was carried out for chromosomal parameters which classified the studied ecotypes into five classes.