灰斑病所致大豆品质与产量损失的研究

Studies on quality and yield loss caused by Cercospora sojina Hara in soybean

采用不同病叶、病粒,对大豆灰斑病所致大豆品质和产量的影响进行了研究,结果发现:灰斑病直接影响大豆叶片全N含量及籽粒氨基酸与蛋白质含量。叶片中的全N含量随病情加重而减少,病粒中17种氨基酸总量、蛋白质和脂肪含量与病叶一样也随病情加重而递减。灰斑病引致的大豆产量损失与病粒率和籽粒病指相关密切,与病粒率的相关系数为0.9723,与籽粒病指的相关系数为0.9763。根据相关系数建立两个方程,用Y^=-0.1890+1.4063X10.7993(X1病粒率)和Y^=2.6034+1.338X2(X2病指)可预测大豆由灰斑病病粒引致的减产量,用n’=Int[(YBL×100-8)]/(5+1)可预测当年大豆的等级,并以EL=YM×(1-YLL)×PW n’预测经济损失。

Artifical infected leaves and seeds with Cercospora sojina were analysed for the content of amino acids, protein, fat in infected seeds and all nitrogen in leaves. The results showed that the contents of all nitrogen in leaves, 17 group amino acids, protein, fat in infected seeds were decreased. The change of nutrient substances in infected seeds was relative to disease index. The yield damage had a close correlation with the percent of infected seeds and the disease index of infected seeds, and the coefficiency of correlation was 0. 9723 （ X1 , percent of infected seeds） and 0. 9763 （ X2, diseace index） , respectively. A forecasting model for yield loss was developed as ： = 0. 1890 ＋ 1. 4068X1^0.7993 , with percentage of scabbed seeds as variation and Y = 2. 6034 ＋ 1. 338X2 , with disease index as variation. Two models n＇ =INT[（YBL×100-8）]/（5 ＋1）, and PEL=YM × （1 -YLL）×PWn＇ can be used for forecasting the soybean quality and economic damage.