EVALUATION OF MARKETABLE LEAF YIELD OF FLUTED PUMPKIN IN DIFFERENT ENVIRONMENTS USING ADDITIVE MAIN EFFECTS AND MULTIPLICATIVE INTERACTION (AMMI) MODEL

This study was conducted to determine the yield stability and to analyse the Genotype by Environment Interaction (GEI) of twenty five genotypes of fluted pumpkin genotypes. The experiment was laid out in a randomized complete block design (RCBD) with three replications under four environments using Additive Main effects and Multiplicative Interaction (AMMI) analysis. The mean squares of the analysis of variance revealed significant genotype, environment and GEI on marketable leaf yield per plant. AMMI analysis revealed that the major contributions to treatment sum of squares were environments (3.24%), GEI (46.90%) and genotypes (49.70%), respectively, suggesting that the marketable leaf yield of the genotypes were under the major genotypic effects of GEI. The first two principal component axes (PCA 1 and 2) cumulatively contributed 93.50% of the total GEI and were significant (p ≤ 0.01). The biplot accounted for 85.82% of the total variation. The AMMI model identified genotypes Ftn44, Ftk20, and Fts34 as most stable, while Fta39 with highest yield (398.80g/plant) had the largest negative interaction. The best genotype with respect to Abeokuta location was Ftw21 while Fta39 was the best for Akure area. Therefore, these genotypes can be recommended according to their specific adaptation areas. Abeokuta in the 2012 and 2013 had positive interaction values of 14.38 and 9.46 respectively whereas Akure in 2012 and 2013 recorded negative interaction values of -5.03 and -18.81 respectively. Akure 2013 was the most discriminating environment and had the highest mean yield thus it is considered as a very good environment for cultivation of fluted pumpkin for marketable leaf yield.