Investigation quality of durum wheat landraces and determination of the parents to use in the breeding program

Abstract

The study was conducted to evaluate the quality of durum wheat grain. For this reason, genetic resources are crucial for the identification of parents and the enrichment of the gene pool that can be used in the development of new varieties for better nutrition of people. For this purpose, 131 populations of landraces, 9 promising line and 5 new varieties were used. The experiment was set up in randomized blocks with 7 replications, according to the augmented (increased) experimental design in 2015-2016 growing season. In the study, we examined total nitrogen content, protein ratio, CIE (Commission Internationale Eclairage) wheat color analysis (L* brightness, b* jaundice, a* redness) of 145 genotypes of durum wheat seeds. According to analysis of variance, highly significant differences (P < 0.05 or P < 0.01) were determined for total nitrogen, protein content and CIE L* value, while differences were not significant for b* value and a* value. The superiority of the genotypes was determined by the first two principal components (IPC1 (principle component) and IPC2) in order to create a two-dimensional GT biplot. The sum squares of the first two components were accounted by 45.34% (PC1) and 40.03% (PC2) for genotypes. The GT (genotype x trait) biplot indicated that 9 (nine) sectors occurred among genotypes and quality parameters. On the other hand, three groups occurred among the quality parameters based on the genotypes. The scatter plot demonstrated that there is a high correlation between b* jaundice, and a* redness. The results showed that cultivars and more landraces have general adaptability for all quality parameters, while some genotypes (G79, G78), (G22, G102), (G3) and (G121, G5) showed specific adaptation for N (nitrogen), PC (protein content) and L*, a* and b* values, respectively. According to the biplot techniques, G36 came forward with the N, P and a* value and desirable landraces, G5 for b* value, G30 stable line for all quality parameters, while (G128, G61) and the majority of promising lines (L4, L6) did not come forward with any quality parameters. The results of the study indicated that the majority of landraces can be used as parents to improve the quality of durum wheat varieties. The study indicated that GT biplot can be used to evaluate the genotypes graphically to select the best genotypes for parents to use in breeding programs.