陇东天蓝苜蓿产量构成因素的相关性分析

Correlation analysis of yield components of Longdong black medic

测定了天蓝苜蓿生长旺盛期与鲜草产量形成有关的11个农艺性状,以各性状为自变量,单株产量为因变量,进行多元回归和通径分析.相关分析的结果表明:分枝数、分枝节间数、侧枝数、侧枝节间数、分枝长度侧枝长度、主枝茎粗、侧枝茎粗8个性状与产量呈正相关,其中与分枝数、分枝长度达极显著水平(P<0.01),与分枝节间数、侧枝长度达到显著水平(P<0.05);而与分枝叶柄长度、侧枝叶柄长度、自然高度3个性状呈负相关,其中与自然高度达到极显著水平(P<0.01).通径分析结果表明:11个农艺性状对产量的直接作用由大到小依次为:分枝长度>分枝节间数>分枝数>侧枝长度>分枝茎粗>侧枝节间数>侧枝茎粗>侧枝数>侧枝叶柄长度>主枝叶柄长度>自然高度,各性状通过分枝长度对产量产生较大的正向间接作用,通过自然高度表现出较大的负向间接作用,分枝长度、分枝节间数对产量的形成具有决定性的作用.

Eleven characters related to the fresh yield of Longdong black medic （Medicago lupulina L. cv. longdong ） were studied by the method of correlation analysis and path analysis. The results showed that eight characters including the number of branches, branch nodes, sub-branches, sub-branch nodes, branch length, sub-branch length, branch stem diameter, sub-branch stem diameter were positively correlated with the yield, among which the correlation of fresh yield to the number of branch, branch nodes, branch length, sub-branches, sub-branch nodes were significant or extremely significant,while other 3 characters including length of branch leaf stalk,length of sub-branch leaf stalk,natural height were negatively correlated to the yield, and natural height got extremely significant difference with yield. The result of path analysis showed that the direct effect of eleven characters on the yield was as follows：branch length〉num ber of branch nodes〉number of branches〉length of sub-branches〉branch stem diameter〉 sun-branch nodes〉sub-branch stem diameter〉 number of sub-branches〉length of sub-branch leaf stalk〉length of branch leaf stalk〉natural height . Each character had larger positive indirect effect on the yield through length of branch,and had larger negative indirect effect through natural height. Length of branch,number of branch nodes had decisive significance to the black medic fresh yield.