Genotype×Environment Interaction of Maize Hybrids under Intercropping With Sweet Potato in Indonesia

Abstract

Background and Objectives: Intercropping of maize with sweet potato is one of cropping systems to improve land use efficiency of maize and sweet potato. The goals of the research were to study G×E interaction and to select adaptive maize hybrid for intercropping with sweet potato. Materials and Methods: Two experiments were set up in Bandung, Indonesia during rainy and dry season. The genetic materials were 13 new and one commercial check hybrids. These materials were cultivated based on a split plot design arrangement with two replications which the main plot comprised maize sole cropping and maize/sweet potato inter-cropping and the sub-plot was the hybrid. Data analysis covered the analysis of variance of maize hybrid in the maize sole cropping and in the intercropping system with sweet potato during both rainy and dry seasons. Homogeneity of variance error was tested using Bartlett test. Combined ANOVA was pursued to determine the interaction of G×E interaction (GEI) when variance errors were homogenous. Adaptability of maize hybrids was determined using genotype and genotype-environment interaction (GGE) biplot analysis. Results: The adaptive maize for intercropping with sweet potato was selected based on their land equivalent ratio (LER) and competitive ratio (CR). Genotype 3×4 was selected as potential hybrid variety for intercropping with sweet potato. Conclusion: The G×E interaction (GEI) plays an important role for male flowering and yield as well as genotype in this study. Selection of stable and adaptive maize hybrid variety for intercropping with sweet potato requires further multi-environment evaluation in several locations in Indonesia. Key