Evaluation of diversity in Iranian ecotypes of alfalfa using forage quality components

Forage quality components of 47 alfalfa ecotypes were studied using near infrared reflectance spectroscopy (NIRS). Results of correlation coefficient among the studied traits showed that dry matter digestibility (DMD) had a positive significant correlation with crude protein (CP) (0.67), and a negative significant one with crude fiber (CF) (-0.51) and acid detergent fiber (ADF) (-0.96). However, correlation between CP and CF (-0.60) and ADF (-0.52) was significantly negative, A positive significant correlation was estimated between CF and ADF (0.37). Result of regression analysis showed that CF and WSC justified 63.5% and 7% of the total variation in ash content, respectively. Hence carbohydrates are the most important variables in determination of total ash content. For evaluating of Mahalanobis distance, the ecotypes were classified into five groups according to their geographical locations and the results illustrated a high distance between the western ecotypes and the others. However, a similarity between the central ecotypes (Esfahan and Chaharmahalo Bakhtiari) and the eastern one (Khorasan, Golestan and Semnan) was clarified. By principal components analysis, DMD, CP, ADF and metabolism energy (ME) were introduced as the most important indicators in forage quality. A Depicted Bi-Plot based on PC1 and PC2, elucidated a high dispersal and diversity among ecotypes and indicated the appropriate ecotypes for utilizing in breeding programs. Cluster analysis using Between-Group Linkage method was performed and depicted dendrogram illustrated a high diversity in forage quality components in ecotypes even those collected from one province. As a whole, the results showed that there is a high potential for selection of desirable parents and usage of heterosis in breeding programs. The results of correlation between the traits could be used for the selection of plants with good quality traits.