Studies on Relations between Coldhardiness and Morphological Characters after Fall Defoliation of Different Alfalfa Cultivars

Five various alfalfa cultivars were used as materials, morphological characters after fall defoliation of sowing year were measured, and evaluated by regrowth ratio after controlled cold treatment. The results showed among the regrowth traits after fall defoliation, regrowth plants height was not correlative observably with coldhardiness since the correlative coefficient of them was just -0.389. But the phenotype score of fall regrowth after first cutting and early growth were correlative remarkably with coldhardiness (R=-0.828,R=0.838,P0.05).