PERFORMANCE EVALUATION AND GRAIN YIELD STABILITY OF RELEASED UPLAND RICE (ORYZA SATIVA L.) VARIETIES AT SOUTHWESTERN PART OF ETHIOPIA, JIMMA ZONE

Abstract

In Ethiopia, rice is one of the most important strategic food security crops and it becomes the
source of income. In Southwestern part of Ethiopia, especially in Jimma zone, lack of high
yielding, biotic and abiotic stress tolerant upland rice varieties were major problem for the
reduction of yield. The objective of the present study was to estimate the magnitude of GEI and
to identify high yielding and stable upland rice varieties for Jimma zone and to recommend for
large scale planting. A total of seven (including one check) rice genotypes were evaluated in
randomized complete block design (RCBD) with three replications at Southwestern Ethiopia,
Jimma zone of Melko, Shebe and Kersa under main season conditions for two main seasons
(2021 to 2022). The combined ANOVA revealed significant variation among G, E and GEI for
mean grain yield of seven upland rice genotypes. The relative contribution of E,G, and GEI
indicated that environment was the most important source of variation for grain yield
performance. E, explained 68.14% of total sum of square (SS) of grain yield, while GEI
accounted for 20.73% and G contributed 4.98%.The first 2 principal components (PC1 and PC2)
were used to create a 2-dimensional GGE bi-plot and explained 55.36 and 26.36 % of GGE sum
of squares, respectively with a total of 81.72% for yield variation. The GGE biplot identified
three rice growing mega-environments. The first mega environment consisted of environments
Melko 2022 (M22), Melko 2021 (M21) and Kersa 2021 with the vertex genotype of Shaga
(SHG) and Second mega environment consists of Kersa 2022 (K22) with the vertex genotype of
Nerica-4 (NE) and third mega environment consists of Shebe 2021 and Shebe 2022 with the
vertex genotype of Wanzaye (WZ). Melko 2022 was ideal environment for rice evaluation and
rice variety, Shaga was found to be benchmark/ideal genotype and could be used as check to
evaluate the performance of other genotypes and also can be recommended for wider cultivation
in the tested locations and similar agro-ecologies.