RESUMEN
Background: The production of high-oil-yielding hybrid varieties is a primary objective in oilseed rape (Brassica napus L.) breeding programs. Biometric genetic experiments such as line × tester provide valuable insights into the genetic structure of traits associated with high oil yield. Methods: In this study, 21 winter hybrids of oilseed rape were evaluated, which were generated by crossing three restorers with seven CMS lines. The experiment was conducted using a line × tester experiment based on a completely randomized block design. Phenological, agronomic, yield, and oil yield components were assessed in this study. The ideal genotype selection index (SIIG) methodology was also employed to identify superior hybrids based on all studied traits simultaneously. Results: Significant differences were observed between the obtained hybrids and the check cultivars. Heritability analysis revealed that phenological traits were primarily controlled by additive effects, while agronomic and qualitative traits were mainly influenced by non-additive gene effects. Both broad-sense and narrow-sense heritability exhibited a wide range, underscoring the importance of genetic variance. Notably, the hybrids T1 × L5, T1 × L6, and T3 × L1 showed significant specific combining ability values of 394.74, 541.73, and 1236.79, respectively, making them the top specific combinations for increasing seed yield. Based on the SIIG index, hybrids T3 × L1, T1 × L5, T1 × L3, and T2 × L3 emerged as high-oil-yielding hybrids with desirable agronomic traits. Conclusions: The identified superior hybrids by line × tester and SIIG approaches hold promise for the development of high-yielding oilseed rape cultivars with desirable agronomic traits in oilseed rape breeding programs.
RESUMEN
High molecular weight glutenin subunits (HMW-GSs) at the Glu-1 loci play an important role in the variation of dough strength, elasticity, and end-use quality of bread wheat. Multilocation trials in a wide range of climatic conditions and crop management practices help explain the role of HMW-GSs in the rheological properties of dough. In the current study, allelic variation of HMWs and quality scores were determined in 28 bread wheat cultivars across a wide range of climates and locations in Iran. Twelve HMW-GSs subunits (3 at Glu-A1, 7 at Glu-B1 and 2 at Glu D-1) in 16 unique combinations were identified in the studied cultivars. In the most rheological properties associated with good bread-making quality, the compositions of 1/17 + 18/5 + 10, 1/13 + 16/5 + 10 and 2*/7 + 9/5 + 10 (all with a quality score of 10) had significantly higher values than the other allelic compositions. While, the lowest values were observed in 1/21 + 19/2 + 12 (quality score of 6). The degree of dough softening was significantly greater in 1/21 + 19/2 + 12 than other allelic combinations. At Glu-A1, Glu-B1 and Glu-D1, 2*, 17 + 18 and 5 + 10 had significantly greater qualitative and rheological properties than the other subunits, which are related to the good quality of wheat flour. While null at Glu-A1, subunits 21 + 19 at Glu-B1 and 2 + 12 at Glu-D1 were associated with weak baking quality. Moreover, the highest dough softening values at Glu-A1, Glu-B1 and Glu-D1 were observed in null, 21 + 19 and 2 + 12 subunits, respectively. A negative and significant correlation (P < 0.05) was observed between the degree of dough softening and other qualitative and rheological properties related to good bread-making performance. The results of this study demonstrated the role of HMW-GSs in determining the end-use quality of bread wheat across a wide range of climates and environments. Supplementary Information: The online version contains supplementary material available at 10.1007/s12298-023-01324-6.