مشخصات پژوهش

عنوان	The Study of Forage Yield and its Components in Relations with Resistance to Alfalfa Weevil (Hypera postica Gyll.) in Some of Medicago sativa Genotypes in Hamedan
نوع پژوهش	مقاله چاپ‌شده در مجلات علمی
کلیدواژه‌ها	Alfalfa collection Factor analysis Forage yield Principal component analysis
چکیده	Alfalfa (Medicago sativa L.) is one of the most important perennial forage crops in Iran. The aims of this study were to evaluate phenotypical and genetical variabilities in alfalfa germplasm collections using multivariate analysis and to select the most promising ecotype for further breeding programs. Principal component analysis (PCA) and factor analysis were used for understanding data structure and traits correlation. Forty-six alfalfa ecotypes collected from different regions in Iran were sown and studied in the pattern of Completely Randomized Design (CRD) in a research field at Bu-Ali Sina University, Hamedan, Iran. Some important agronomic traits and the traits related to weevil pest attack were recorded during the growing season in 2012. The data were analyzed by multivariate statistics for determining groups based on their similarities. The studied ecotypes were classified into 4 clusters. Factor analysis was performed for all agronomic traits and reduced them to 4 common factors which accounted for 82% of the total variations among the ecotypes studied. Collected data were centered and scaled to unit variance and analyzed by principal component analysis. The results showed that the first four PCs contributed to 0.7% of the total variability among the ecotypes. In other words, data reduction would let the plant breeders to reduce field costs required to obtain the genetic parameter estimates necessary to construct selection indices.
پژوهشگران	مهدی کاکایی (نفر اول)، حجت اله مظاهری لقب (نفر دوم)