Evaluation of indices related to grain quality, chemical and rheological properties of bread wheat using biplot analysis

To study the genetic variation in baking quality related characteristics of 30 wheat bread recombinant inbred lines, an experiment was conducted based on randomized complete blocks with two replications. following traits were measured on each plot: Physical traits of grain (1000-grain weight, hectoliter weight), Chemical traits of grain (humidity (%), dry matter (%), protein content (%), gluten index, wet and dry gluten (%), ash (%) and fat content (%)) and bakihg quality traits of dough by farinograph method including; water absorption (%), mixing dough, dough development time, degree of softening (after 10 and 20 min), resistance to extension and dough stability. Analysis of variance showed significant differences among genotypes for all traits. Factor analysis resulted in six factors that determined 79.14% of the total variation. The first factor defined 25.76% of variation including farinogram triats. The second factor explained 15.81% of variation including; qualitative traits. Third factor explained 12.29% of variation included; 1000-grain weight, mixing dough and dry. The fifth factor along with the sixth factor accounted for 15.52% of total variation. In this study, the purpose of using GGE biplot method on the obtained data, was investigate the relationship between different traits and determining the relative importance of traits associated with quality and yield. According to results from GT biplot, traits of dough development time, dry matter (%), resistance to extension, dough stability, gluten index, water absorption (%) and hectoliter weight can be introduced as the best and most important traits related to quality and yield, as well as the appropriate indicators in the selection of genotypes of of bread wheat. Among bread wheat recombinant inbred lines and based on all evaluation factors, line 16 was the closest line to the ideal genotype. These findings would be employed in bread wheat breeding program to improve the baking quality characteristics in breeding materials.