Genetic Improvement for Yield and Its Components through Induced Chemical and Physical Mutagenesis in Peanut (Arachis Hypogaea L.)

The present study was conducted at private Farm at El-Sharqia Governorate, Egypt under supervision of Agronomy Department, Faculty of Agriculture, Suez Canal University, Ismailia, Egypt. Four cultivars of peanut were used in this work namely NC9, Gregory, Bold, and Runner. This work aimed to study the induction of genetic variation in peanut using Sodium azide (NaN₃; Mw=65.01) with two doses (1×10^-3) and (3×10^-3) and three doses of Gamma rays (10, 30 and 50kr) to induce mutagenesis. M1 and M2 seeds per dose for each genotype including the control were sown in a randomized complete block design (RCBD) with three replications in 2017 and 2018 summer seasons. Analysis of variance showed that there were significant differences between genotypes under sodium azide and gamma rays for most studied traits in M1 and M2 generations. Number of primary branches was significantly affected by sodium azide concentrations, however all genotypes gave low number of primary branches under 0.003M than other treatments in both generations. Gregory and NC9 cultivars under Gamma rays had the high number of branches/plant in M1 and M2 generation when treated with 0.001M compared with 0.003M. The average of plant height was affected by radiation mutagen and higher the effect of sodium azide mutagen in both generations. 100-seed weight was affected significantly by sodium azide mutagen more than those by radiation mutagen in both generations. Maximum values of seed yield/plant were recorded for the NC9 followed by Gregory in both generations.  NC9 and Gregory had the maximum values of seed yield/plant, when they treated by 0.001m in both generations. Mean values of oil content were increased significantly with increasing concentration of gamma rays doses in M1 and M2 at 10kr, 30kr and 50kr, respectively compared with control. The Bold cultivar had the highest values 51.34% and 50.39% and runner cultivar with values 49.02 and 49.66, when they treated with 50 kr and 30kr in M1 generation. The Runner and NC9 gave the high values for yield and its components and oil content of most genetic parameters under different mutagens in M1 and M2 generations for the most studied traits. The results of heritability, showed moderate to high values for most characters under studied in different mutagens in M1 and M2 generations. Pod yield/plant under the effect of sodium azide appears high positive correlation coefficients with each of seed yield/plant (0.869 and 0.928) during two the generations and 100-seed weight (0.643) in M1 generation