Analysis of Multi-Environment Yield Trails of Clusterbean [Cyamopsis tetragonoloba (L.) Taub.] Genotypes using GGE Biplot 

A set of 42 clusterbean genotypes were evaluated for yield attributing trait pods per plant over three environments. Pooled analysis of variance showed that Environments (E) explained highest proportion of variation for pods per plant, accounting for 42.16% of it, followed by G × E interactions (GEI) effects (31.1%) and genotype (26.7%). Higher effect of GEI compared to G alone indicated the possible existence of mega environments among the testing locations. The biplot explained 89% of the total variation relative to G plus GEI. Based on environment discrimination test, Environment 1(Madurai) is the ideal environment. Which Won Where (WWW) Polygon identified the most diverse genotypes namely M local, T local, RGC1055, RGC1033, HGS75, MRSG6 and CAZG10-2 were found to be highly diverse. These genotypes also occupied the convex of the hull. The genotype CAZG10-2 won in the Environment1 (E1) and the genotype HGS75 won in both environments E2 (Coimbatore) and E3 (Kovilpatti). Genotype stability test identified genotypes namely RGC1031, R local, HGS75, MRG1786, HGS2-1, HGS365, RGC1003, HGS2-4, HGS2-20 and PNB were stable over the other genotypes as they placed near to the Average Environment Coordination (AEC) abscissa.