[Yield characteristics and genetic diversity of main alfalfa varieties in China]

The dry matter (DM) yield and its characteristics of 28 alfalfa varieties were evaluated in the 4th year under space sowing condition. The results showed that there existed significant difference (P<0.01) in DM yield and its characteristics among the varieties. The highest and higher DM yield were obtained form varieties Xinjiang Deye (452.8 g x plant(-1)) and Gannong No. 3 (373.0 g x plant(-1)), respectively, and the varieties with the highest height and branch/plant at the 3rd cutting were Gannong No. 3, Xinjiang Deye, Weixian, Tumu No. 2, Xinmu No. 1, and Zhaodong. The correlation analysis between DM yield and its characteristics indicated that the main factors affecting yield were the height and the branch/plant. The genetic diversity of DM yield and its components in 28 alfalfa varieties showed that the variations of DM yield and yield components of within-variety were larger than those of among-variety in majority of test varieties. The CV of all characteristics were presented in order of 3rd No. branch/plant>DM yield/plant>1st No. branch/plant>2nd No. branch/plant>Spring height>3rd height>2nd height>leaf width>budding height>leaf length>1st height.