بررسي تنوع ژنتيكي عملكرد بذر و صفات مرفولوژيكي در توده هاي علف پشمكي (Bromus tomentellus)

Genetic variation for seed yield and morphological traits in Bromus tomentellus populations

In order to study the relationship of seed yield with its components, 11 genotypes of Bromus tomentellus were examined using complete block design with three replications. The data were collected and analyzed for ear emergence date, pollination date, maturity date, stem density, plant height, peduncle length, spikelet number, thousand grain weight, panicle length, seeds weight per panicle, seeds number per panicle, dry matter yield, seed yield, and harvest index. There were significant differences among genotypes for all the traits except for seeds weight per panicle. The genotypes 587P10, 587P6 and 587P3 originated from Esfahan, Iran, with average values of 3.12 to 3.75 ton/ha and 535 to 697 kg/ha had the highest dry matter and seed production, respectively. The results of phenotypic correlation analysis showed that seed yield had positive and significant correlation with stem density and dry matter yield. Results of principal component analysis for Bromus tomentellus showed that the first three components explained 89% of the total variation. Phonological traits and forage yield in the first and seed yield and stem density in the second and third components were the most important traits. Using cluster analysis the genotypes were grouped into 3 clusters. The genotypes in cluster 3 had higher values for seed and forage yield. Distribution of genotypes based on the first two components scores was in agreement with cluster analysis.