ISSN: 0041-3216 (Online), 0041-3216 (Print)
Volume 70 Number 4
Genetic variation in agronomic characters of lima beans induced by seed irradiation
The effects of gamma irradiation on dry seeds of two cultivars of lima beans, Phaseolus lunatus L., cv. TPL 2508 and TPL 84A, were investigated under dosages ranging from 5.0 to 25.0 kR. The pooled mean ID50 for seedling survival for the two cultivars was 16.6 kR, whereas 10.0 kR and 15.0 kR were the most effective dosages for mutation frequency for TPL 2508 and TPL 84A, respectively. The irradiation induced higher genetic variation of up to four times within the cultivars under study compared to the unirradiated population. It has been observed in the present investigations that in lima beans, seed yield could be increased through selection for number of pods plant-1 among irradiated populations because of its higher genetic variance, heritability, and genetic gain compared to the unirradiated population.
Keywords: Genetic variation; Gamma irradiation; Mutagenic effectiveness