不同磷素水平下大豆农艺性状对产量贡献的通径分析

以东北地区广泛栽培的226个大豆品种为材料，在常磷与低磷处理下，测定了与产量有关的百粒重、株高、节数、分枝数4个农艺性状。并进行通径系数分析．结果表明：磷高效基因型大豆在常磷条件下百粒重与株高负相关，株高与节数呈极显著正相关，节数与分枝数呈正相关，百粒重与节数负相关。百粒重与分枝数呈极显著负相关，株高与分枝数呈负相关；低磷条件下百粒重与株高负相关，相关系数小于常磷条件。株高与节数为极显著正相关，节数与分枝数相关显著，百粒重与节数为负相关．通径系数表明，磷高效基因型在常磷条件下对产量直接贡献最大的是节数，株高对产量负的影响最大，粒重对产量是正影响，分枝数对产量无影响。

Path Analysis of Agronomic Character's Contribution towards Output of Soybean under Different Level of Phosphorus

The paper selected 226 kinds of soybean widely planted in the northeast as experimental material,and measured four agronomic characters related to output such as 100-grain weight,plant height,node number and number of branches in normal and low level of phosphorus.Above these indexes were analyzed with path analysis.The results showed: Under normal level of phosphorus,100-grain weight of soybean genotype with high phosphorus absorption efficiency negatively correlated with plant height,plant height and node number were significantly positive correlation.but the relationship between node number and number of branches had a tendency to significantly positive correlation,100-grain weight and node number were negative correlation,100-grain weight and number of branches were significantly negative correlation,plant height was negatively correlated with number of branches;However under low level of phosphorus,100-grain weight was negatively correlated with plant height,but their correlation coefficient was less than those of normal level of phosphorus;the relationship between plant height and node number was the most significantly positive correlation,node number was markbly correlated with number of branches,100-grain weight and node number was negative correlation.The results of path analysis indicated: Node number of soybean genotype with high phosphorus ` contribution toward output was the most and direct in normal level of phosphorus,negative effect of plant height on output was the most,effect of grain weight on output was positive,but number of branches did not affect output.