Study on Genetic Divergence Using Multivariate Analysis for Bread Wheat (Triticum aestivum L.) Genotypes

The research was conducted at KARC in 2023 on 50 bread wheat genotypes to assess traits contributing to phenotypic variation, cluster genotypes into divergent groups, estimate genetic distances between clusters, and evaluate genotypes for yellow and stem rust resistance. Analysis of variance revealed significant genetic variability (p<0.01) for eight out of ten traits, including days to 50% heading, days to 90% maturity, grain yield, and rust disease severity, with plant height and thousand kernel weight also showing significant variation (p<0.05). The genotypes displayed a wide range of values: days to 50% heading varied from 61 to 77 days, with four genotypes heading earlier than the check variety Abay. Thousand kernel weight ranged from 18.0 g to 41.0 g, with 30 genotypes exceeding the check variety. Grain yield also varied significantly, with some genotypes outperforming Abay, making them promising for breeding programs. Cluster analysis categorized the genotypes into five clusters, showing genetic diversity. Significant genetic differences were found between clusters, particularly between Cluster I and Cluster V, suggesting that crossing genotypes from these clusters could yield beneficial recombinants with improved traits. Principal component analysis accounted for 73.45% of the total variation, with key traits like grain yield and thousand kernel weight contributing notably to the observed variation. Disease resistance analysis revealed that 48% of genotypes had high resistance to yellow rust, while 82% showed strong resistance to stem rust. These findings underline the potential for breeding high-yielding and disease-resistant wheat varieties, emphasizing the value of genetic diversity in wheat breeding programs