Biplot analysis of diallel crosses for yield and some of morphological traits in wheat

Abstract

A study of combining ability for improving bread wheat yield and yield components was carried out via genotype plus genotype\u2009×\u2009environment (GGE) biplot. Six bread wheat genotypes were used to obtain F1 in a diallel cross matings at the Gachsaran Field Station, Dryland Agricultural Research Institute during 2012–2013 cropping seasons. Analysis of variance indicated significant effects of genotypes, general combining ability (GCA) and specific combining ability (SCA) for all of the studied traits. The highest values of plant height (108.15\xa0cm), peduncle length (33.95\xa0cm) and grain yield (265.5\xa0g\xa0m−1) were obtained in g6 (DAMARA-6 ICW99-0427-8AP-0AP-0AP-3AP-0AP). GGE biplot analysis showed that g4 (Kouhdasht) and g6 (DAMARA-6 ICW99-0427-8AP-0AP-0AP-3AP-0AP) were as the best general combiners for days to maturity, plant height and grain yield, whereas g1 (Karim) had the highest GCA effects for spike length and thousand grain weight, and g3 (Aflak) showed the highest GCA effects in terms of peduncle length. Meanwhile, g6 showed large SCA effects for thousand grain weight and grain yield, while g4 had high SCA effects for spike length. g5 (PASTOR/2*SITTA//PBW343*2/KUKUNACMSS04Y00333S-099Y-099ZTM-099Y-099\xa0M-3WGY-0B) had large SCA effects for peduncle length. Because of significant effects of mid-parent heterosis for grain yield, g4\u2009×\u2009g6 was considered as the best possible cross for improvement of this trait. Based on the results of present study, GGE biplot indicated good potential for identifying suitable parents and heterotic crosses and the best hybrids according to diallel mating design.