Induced Chromosomal Abnormality and Pollen Sterility in Wild and Cultivated Urd and Mung Beans

Abstract

Seeds of Vigna sublobata (wild), V. radiata cv. PS 16 and V. mungo cv. T 9 (both cultivars) were used for the induction of mutations with EMS and gamma rays. Four dose treatments of each of these mutagens (EMS: 0.1%, 0.2%, 0.3% and 0.4%; gamma rays: 10 KR, 20 KR, 30 KR and 40 KR; EMS+gamma rays: 0.1%+10 KR, 0.2%+20 KR, 0.3%+30 KR and 0.4%+40 KR) were employed. In M₁ and M₂ generations of all the three species, there is a dose dependent increase in the frequencies of different kinds of meiotic chromosomal abnormalites. The presence of univalents, trivalents and multivalents suggests that mutagenesis did result in point mutations or deletions, inversions and translocations. The spectrum and frequencies of different kinds of chromosomal abnormalities extend support to the exchange hypothesis. There is a dose dependnt increase in the percent pollen sterility; the ‘r’ value between chromosomal abnormality and pollen sterility is positive and highly significant.