GENOTYPE BY ENVIRONMENT INTERACTION AND YIELD STABILITY ANALYSIS OF DOUBLED HAPLOID LINES OF UPLAND RICE

The aims of this research was to determine the effect of genotype-by-environment (G x E) interaction ongrain yield among upland rice doubled haploid lines (DH) of upland ricein order to obtain stable and high yielding lines through multilocation yield trials. Fourteen DH lines and two upland varieties i.e. Inpago 10 and Limboto were planted at 6 different locations in Indonesia, i.e. Bogor, Indramayu and Sukabumi (West Java Province), Malang and Blitar (East Java Province), and East Lampung (Lampung Province). In each location, the experimental design was randomized complete block design with three replications nested in locations. Stability was analyzed using linear regression model. Combined analysis of variance showed that the effects of location, genotype and interaction of genotype x location were highly significant (p<0.01) for grain yield. There was considerable variation for grain mean yield among both genotypes (DH lines) and environments (locations) which made it difficult to select stable lines in response to environmental change. DH lines of ST6 and ST9 were classified as stable and widely adapted in all locations based on Finlay-Wilkinson, Eberhart-Russel and AMMI stability analysis. ST13 was classified as stable only by Finlay and Wilkinson's analysis, but achieved the highest average yield of six locations(5.00 tons ha(-1)), higher than check variety Inpago 10 (4.03 tons ha(-1)),and similar to Limboto (4.98 tons ha(-1) ).ST6, ST9, and ST13 DH lines also had high yield potential, i.e. 6.26, 6.28, and 7.18 tons ha(-1), respectively. In addition, AMMI analysis also showed that ST1 was DH lines specifically adapted to Malang, while ST7 was specifically adapted to Blitar.