GENOTYPE BY ENVIRONMENT INTERACTION AND STABILITY ANALYSIS OF SEED YIELD, AGRONOMIC CHARACTERS IN MUNGBEAN (VIGNA RADIATA L. WILCZEK) GENOTYPES

Field experiments were conducted in monsoon season, 2011 at Food Legumes Section, Department of Agricultural Research (DAR), Yezin, Tatkon Research Farm and Sebin Research Farm by using Randomized Complete Block Design with four replications. Seven mungbean breeding lines (three lines from Yezin-9 x VC-6371-23-11, three lines from NM-92 x VC-6368-46-40 and one line from NM-92 mutant) and six released varieties were used to examine the genotype x environment (G x E) interaction on seed yield and to identify stable and high yielding mungbean genotypes across environments. Genotype x environment interaction was observed in all recorded characters except for seeds per pod. Mean seed yield performance in three environments indicated genotype YM-03-2-6 which produced the highest seed yield of 9.73 g per plant followed by Yezin-9 (9.57 g). YM-03-2-6 and Yezin-9 were stable genotypes with high mean yield that genotypes produced close to unity (b_i=1), non significant differences from regression coefficient (b_i) and deviation from regression (S_di^2) due to stability analysis with close to the zero of IPCA scores from the results of AMMI analysis. Genotype YM-03-2-5 produced average mean yield with high b_i and S_di^2 value and coupled with high positive interaction in Tatkon Research Farm while genotype YM-03-2-2 also produced average yield mean yield with low b_i and high S_di^2 value and coupled with high positive interaction in Sebin Research Farm. This showed that genotype YM-03-2-5 and YM-03-2-2 were better responsive to high yielding environment and poor environment, respectively. So, both the Stability analysis (Eberhart and Russell, 1966) and additive main effects and multiplicative interactions (AMMI) analysis considered YM-03-2-6 and Yezin-9 could be used as broad adaption varieties with high yield in all tested environments. Genotypes that could be used as good adaptation to specific environments were YM-03-2-5 for Tatkon Research Farm and YM-03-2-2 for Sebin Research Farm.