Effects of low-dose gamma radiation on quality and storability of groundnut (Arachis hypogaea L.) seeds

Shelled and unshelled groundnut seeds ( cv. Chinese ) subjected to low doses of gamma irradiation (0,1,2,3,4 and 5 Gy) and stored under ambient conditions were evaluated using eight tri-weekly intervals over a five-month storage period for seed quality and storability. The experimental design adopted was a Completely Randomized Design (CRD) with each of the twelve treatments replicated three times. Data comprising Physiological, Sanitary and Genetic seed qualities collected included moisture content, germination percentage, germination speed and peak, root and shoot lengths, seedling vigour, percentage emergence, days to 50% flowering, leaf and petiole colours, Statistically significant differences between irradiated shelled and unshelled seeds and their controls were observed for root and shoot lengths as well as speed of germination. Unshelled seeds recorded significantly (p \(\:\le\:\)0.05) lower seed moisture content with higher values for percentage germination, speed and peak of germination. Pathogen infectivity however rose significantly (p \(\:\le\:\:\)0.05) from 22% to 79.9% over the storage period. Days to seedling emergence, petiole and leaf colour as components of genetic seed quality were not affected significantly by irradiation despite the seed form with both shelled and unshelled having similar seed germinations despite irradiation dose. A dose range of 2–4 Gy was observed to have had slight stimulatory effect on seed germination and seedling vigour of both seed forms. Further investigations using 2–4 Gy radiation doses are recommended.