摘要
研究了苹果黄蚜危害苹果树新梢第二、四叶的百叶蚜量 (x)与苹果产量损失率 (y)的相关式为y =- 16 .0 0 9975 +0 .0 370 7x(r=0 .94 73) ,分析提出了其经济阈值为 2 5 0叶 (第二、四叶 )蚜量 12 5 0头。为了节省调查工时 ,根据第二、四叶卷叶率 (y)与蚜量 (x)的相关式y =- 0 .0 6 80 1+0 .0 0 70 6 9x(r=0 .994 5 ) ,求得卷叶率 ,即其经济阈值也可为第二、四叶卷叶率 10 %。
The relationship between the amount of Aphis citricala on one hundred leaves (first leaf and fourth leaf)(x)and the yield loss rate of apple(y)was studied,their relative formura:y=-16.009975+0.03707x(r=0.9473).Through analysis,its economic threshold:1250 aphids on first leaf and fourth leaf of 250 leaves.In order to save man-power and time of survey,we used the relative formula of aphid amount(x)and the rate of roll leaf(y):y=-0.06801+0.007069x(r=0.9945)to find y,i.e.the economic threshold might be 10% of rate roll leaf rate also.
出处
《山东农业大学学报(自然科学版)》
CSCD
北大核心
2002年第1期87-88,100,共3页
Journal of Shandong Agricultural University:Natural Science Edition
关键词
苹果
苹果黄蚜
卷叶率
经济阈值
经济损失
apple
Aphis citricala
the rate of roll leaf
economic threshold