Affiliation:
1. Department of Agronomy and Plant Breeding, Karaj Branch Islamic Azad University Karaj Iran
2. Oil Crops Research Department, Seed and Plant Improvement Institute Agricultural Research, Education and Extension Organization (AREEO) Karaj Iran
Abstract
AbstractBackgroundThe 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.MethodsIn 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.ResultsSignificant 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.ConclusionsThe 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.