霜霉病对苜蓿幼苗生长和结瘤的影响  

Influence of Downy Mildew on Growth and Root Nodulation of Seedlings of Alfalfa.

作　　者：侯天爵[1] 周淑清[1] 

机构地区：[1]中国农业科学院草原研究所

出　　处：《中国草地》1997年第2期52-54,共3页Grassland of China

摘　　要：接种试验表明，霜霉病对苜蓿幼苗生长发育影响显著，感病植株幼苗高度减低４２．６％～５２．０％，生长速度明显减慢，健苗的平均增长率为４５．７％，而病苗仅为２２．７％；地下部主根入土深度（根长）减少２７％，根的直径（根颈部）减少４４．３％，根鲜重减少７５％，根瘤的数量减少５４．１％，而且病苗的根瘤均为白色无效根瘤，健苗的根瘤约半数为粉红色的有效根病。根的长度与根瘤数量呈明显正相关，健苗的相关系数ｒ＝０．８６８６，病苗的相关系数ｒ＝０．５６７９，说明幼苗感病后根瘤数量明显减少并很快失效。Inoculation test showed that the influence of downy mildew on the growth of seedlings of alfalfa was significant. The height of diseased seedlings decreased by 42.6%～52.0% in compared with health seedlings. The average rate of growth of the health seedlings was 45.7%, while it was just 22.7% in diseased plants. The length of main root was reduced by 27%, the diameter of root was reduced by 44.3%, the weight of the root was reduced by 70%, and the root nodulation decreased by 54.1% in compared with the health seedlings. On the diseased seedlings, all of the root nodules were ineffective. The correlation analysis showed, that there was direct relationship between the length of root and root nodulation.

关 键 词：苜蓿 霜霉病 结瘤 生长 

分 类 号：S551.7[农业科学—作物学] S435.5