GENOTYPE X ENVIRONMENT ANALYSIS OF TRAITS RELATED TO GRAIN YIELD OF UPLAND RICE

Abstract

Nine rice genotypes were cultivated over four environments generated from the early and late rains in
two ecologies located forest and derived savannah ecologies in south western Nigeria to characterize
genotype compatibility to cultivation environment. Grain weight per plant (GWPP) and other grain
yield components were subjected to the additive main effect and multiplicative interaction (AMMI).
Genotype and genotype by environment (GGE) analysis of GWPP was additionally done to identify
genotypes with high but stable grain production and gain insight into the performance of grain yield
components in order to assist in plant breeding efforts. The genotypic effect was significant for all
traits except number of tillers(NT) and grain weight per panicle (GWPPN). The environment was
significant for all traits while the interaction of genotype and environment (G x E) was equally
significant for all traits except GWPPN. The AMMI PC1 was significant for all traits while the AMMI
PC2 was significant only for TN, panicle secondary branching, spikelets number per panicle and
spikelets fertility. Environment explained a significant 90.9% of the variation through the AMMI
analysis for GWPP. Genotype and G x E captured equally significant 1.8% and 4.8% respectively. The
PC1 for GWPP was responsible for 94.2% of the G x E. The GGE biplot for GWPP summarized
98.3% of the total variation and separated the four environments into three with similar genotypes.
WAB 56-50 was best for GWPP but less stable compared to ITA 321, IRAT 170 and WAB 181-18 with
above average but stable grain production.