Genotype · environment interaction and identification of dual-season cultivars in chickpea

Abstract

Genotype-environment (G x E) interaction plays a significant role in the relative expression of different cultivars in different environments. The productivity of chickpea in the Central and West Asia and North Africa (CWANA) region is constrained mainly by terminal drought because it is traditionally cultivated as a spring crop using conserved soil moisture. Studies conducted at the International Center for Agricultural Research in the Dry Areas (ICARDA) have clearly demonstrated that planting chickpea in winter can produce almost twice the yield of the spring crop. This study examined the extent and nature of G x E interaction on the yield of chickpea and identified genotypes that can produce high yields in both seasons. Sixteen sets of genotypes were evaluated in lattice designs at two contrasting locations in Syria and Lebanon in both spring and winter. In the analysis of individual trials, spatial variability was modeled in terms of block structure, linear trend across columns, and auto correlated plot errors. Genotype x season interaction was significant. The best linear unbiased predictor (BLUP) was obtained from individual analyses and adjusted across trials to screen from all the entries. Keeping in view the occurrence of high G x E interaction, and small number of genotypes in individual trials, selection efficiency was kept at a relatively moderate percentage (10%) to cover most of the desirable genotypes. The dual-season lines identified were FLIP98-121C, FLIP97-49C, FLIP97-50C, FLIP97-21C, S95082, FLIP97-17C, FLIP98-56C, and FLIP97-24C for Syria; and FLIP98-90C, FLIP99-37C, FLIP 97-56C, S96026, FLIP97-131C, FLIP 98-21C, FLIP01-63C, FLIP97-93C, and S95082 for Lebanon. We suggest that these genotypes be evaluated in multi-location trials with larger plots to identify the most desirable promising lines suitable for dual-season planting. The approach used in this study can be used to identify dual-season varieties in different target environments.