Trait profiling and genotype selection in oilseed rape using genotype by trait and genotype by yield*trait approaches

Abstract

Selection and breeding for high‐yielding in oilseed rape have always been one of the leading objectives for oilseed rape breeders. This process becomes more complicated when all quantitative traits are considered in selection in addition to grain yield. In the present study, 18 oilseed rape genotypes along with 2 check cultivars (RGS003 and Dalgan) were evaluated across 16 environments (a combination of 2 years and eight locations) in the tropical climate regions of Iran during 2018–2019 and 2019–2020 cropping seasons. The experiments were conducted in a format of randomized complete block design (RCBD) with three replications. The obtained multienvironmental trial data were utilized to conduct multivariate analysis, genotype by trait (GT) biplot, and genotype by yield*trait (GYT) biplot (Breeding, Genetics and Genomics, 1:2019). The GT and GYT biplot accounted for 55.5% and 93.6% of the total variation in the first two main components. Based on multivariate analysis and GT biplot, pod numbers in plant (PNP) and plant height (PH) were chosen as two key traits in spring oilseed rape genotypes for indirect selection due to high variation, strong positive correlation with grain yield (GY), and their high representatively and discriminability in genotype selection. The mean × stability GT biplot represented G10 (SRL‐96‐17) as the superior genotype. Based on the mean × stability GYT biplot, eight above‐average genotypes were identified that took high scores in stability, high‐yielding, and all evaluated quantitative traits at the same time. Based on the superiority index of GYT data, G10 (SRL‐96‐17) and G5 (SRL‐96‐11) indicated the best yield–trait combinations profile and ranked above check cultivars and then selected as superior genotypes. Similarly, cluster analysis using the WARD method also separated eight superior genotypes. Based on the result of the present study, GT ad GYT methodologies are recommended for trait profiling and genotype selection in oilseed rape breeding projects, respectively.

Enhancing yield and oil content in oilseed rape hybrids: Insights from line × tester and SIIG approaches

“…This emphasizes the need for multi‐environment trials to assess trait stability and adaptability across different growing conditions. Consistent with current literature, the present study identified significant genotypic variation in all the studied traits, indicating the presence of high genetic diversity among the tested oilseed rape genotypes (Bakhshi, Amiri Oghan, Rameeh, Zeinalzadeh Tabrizi, et al., 2023 ). Genetic variation serves as the foundation for selecting superior genotypes with desirable traits and is instrumental in breeding programs aimed at improving oilseed rape.…”

“…The results of this study align with previous research highlighting the significant influence of environmental factors on the performance of studied traits in oilseed rape (Perveen et al., 2005 ; Tuncturk et al., 2005 ). Environmental effects on traits such as days to flowering, days to maturity, and yield have been reported in recent studies as well (Bakhshi, Amiri Oghan, Rameeh, Fanaei, et al., 2023 ; Bakhshi, Amiri Oghan, Rameeh, Zeinalzadeh Tabrizi, et al., 2023 ). This emphasizes the need for multi‐environment trials to assess trait stability and adaptability across different growing conditions.…”

“…in recent studies as well Bakhshi, Amiri Oghan, Rameeh, Zeinalzadeh Tabrizi, et al, 2023). This emphasizes the need for multi-environment trials to assess trait stability and adaptability across different growing conditions.…”