Radiation induced polygenic mutation in two common Nigerian Sesame (Sesamum indicum L.) cultivars.

Abstract

In order to study the level of tolerance of Sesame (Sesamum indicum L.) to Fast Neutron Irradiation (FNI) as well as induction of valuable mutants, two sesame cultivars (Ex-Sudan and Kenana-4) were exposed to FNI from an Americium Beryllium source with a flux of 1.5 × 104 ncm-2s-1. Seeds of Ex-Sudan and Kenana-4 were irradiated with 4, 8, 12 and 16 µSv doses of FNI before they were grown to maturity, alongside their respective controls (0 µSv dose of FNI). The parameters investigated include number of flowers per plant, number of capsules per plant, length of capsule, weight per capsule, number of seeds per capsule, percentage flowering and oil content. No significant differences (P ˃ 0.05) were observed for all the yield parameters of sesame plants after exposure of seeds to different doses of FNI except for Length of capsule, weight of capsule and number of seeds per capsule in Ex-Sudan and weight of capsule in Kenana-4. Similarly, the two varieties showed significant differences in oil content (P ≤ 0.01) at different doses of FNI. Even though none of the correlation coefficients were significant, they were generally positive in Ex-Sudan and negative in Kenana-4 suggesting that the two varieties respond to FNI in different ways. 12 and 16 µSv were the most potent dose to induce viable mutant in Sesame especially in Ex-Sudan accession since it resulted in better yield parameters. Therefore FNI may serve as a valuable tool for the improvement of Sesame.