Effects of Different Levels of Gamma Radiation on Growth and Yield Characteristics of Groundnut
M. Thenuja
Department of Crop Science, Faculty of Agriculture, Eastern University, Sri Lanka.
S. Sutharsan
Department of Crop Science, Faculty of Agriculture, Eastern University, Sri Lanka.
L. M. Rifnas *
Department of Agro-technology, University of Colombo Institute for Agro-technology and Rural Sciences, Hambantota, Sri Lanka.
*Author to whom correspondence should be addressed.
Abstract
One of the key strategy for improving the crops is plant mutation breeding, which generates a large germplasm pool to improve crop characteristics. In this field experiment, the effects of different levels of gamma radiation on the growth and yield characteristics of groundnut were investigated. "Gamma chamber 1200 Cobalt-60" research irradiator was used to irradiate the groundnut seeds. Two experiments were conducted, with the first exposing the seeds to gamma radiation levels ranging from 0 to 100 Gy, and the second exposing them to levels from 0 to 500 Gy. Irradiated seeds were sown in poly bags and kept under shade. After 2 weeks, seedlings were transplanted in an open field using a Randomized Complete Block Design with five replications. Growth and yield parameters were collected, and statistical analysis was carried out using SAS 9.1 software, with treatment means compared using DMRT at 0.05 level. Results from experiment one showed no significant (P ≥ 0.05) differences among treatments. However, in experiment two, treatments showed significant differences in the measured variables. Seeds exposed to 200 Gy had increased shoot fresh weight (123.3%), root fresh weight (69.8%), number of pods (46%), 100-seed weight (47.7%), and total yield (65.6%). The study recommends 200 Gy as a more suitable level of gamma radiation to create desirable characteristics in groundnut. In conclusion, gamma radiation can be an effective tool for inducing mutations in plants for crop improvement. The findings of this radiation study could contribute to the improvement of new cultivars of groundnut with desirable traits, such as increased yield and improved plant growth.
Keywords: Crop improvement, gamma radiation, survival rate, mutational breeding