Evaluation of Durum Wheat Cultivars and Promising Lines for Yield and Yield Stability in Warm and Dry Areas using AMMI Model and GGE Biplot

To obtain high yield and stable genotypes, 18 durum wheat cultivars and promising lines along with two commercial durum (Behrang) and bread wheat (Chamran) as check cultivars, were evaluated in four warm and dry regions in Iran including Darab, Ahvaz, Khoramabad and Dezful during two cropping seasons (2013-2015). The experiments were conducted as a RCBD with three replications. Seed yield and some agronomic characteristics were recorded in each location. The results that first two bilinear AMMI model terms were significant and of which the first two terms explained 85.17% of the genotype × environment interaction. Also the results of AMMI model (AMMI1 and AMMI2) indicated that lines no. G5 (DW-93-5), G10 (DW-93-10) and G12 (DW-93-12) were the most stable lines with high mean yield performance. The polygon-view of GGE biplot recognized five superior lines (lines G5 (DW-93-5), G9 (DW-93-9), G13 (DW-93-13), G16 (DW-93-16) and G17 (DW-93-17)) and two mega-environments so that the best genotypes within each environment were determined. Simultaneous evaluation of yield and stability through average environment coordinate (AEC) biplot showed that line no. G5 (DW-93-5) with the highest seed yield and stability was the most stable line. Biplot analysis of correlation among environments revealed that environmental vectors of Khoramabad with three locations including Darab, dezful and Ahvaz were near to 90◦ so; these three locations were different from Khoramabad. Totally, Khoramabad, Darab and dezful locations had high discriminating ability so that were be able to show differences between lines and cultivars at ideal environment, so they had the highest discriminating ability and representativeness. Finally, lines no. G5 (DW-93-5) and G10 (DW-93-10) with high yield, broad adaptability, relative resistance to foliar diseases and seed quality were selected as best line for further investigation and to be candidate as commercial durum wheat cultivars.