草原蝗虫防治指标的研究

STUDY ON THE ACTION THRESHOLD OF THE GRASSLAND GRASSHOPPERS

作者测定了4种蝗虫从孵化至成虫期的食量,把草原蝗虫划分为以红翅皱膝蝗、邱氏异爪蝗和狭翅雏蝗为代表的大、中、小三种食量类型,混合种群虫口密度(x)与其对牧草取食量(y)的模型为y=16.4732x。通过野外混合种群不同密度下对牧草产量损失的测定,回归式为(?)=-20.8070+14.4143x±15.56(r=0.9993,F>F_(0.01)),两种方法计算的防治指标分别为21.7、26.2头/m^2,其经济允许损失均为8.8％。大、中、小三种食料类型的防治指标分别为5.2、17.6和32.3头/m^2。

Based on the individual grass consumption test of four grasshopper species from hatching to adult stage, the feeding types of grassland grasshoppers were classified as more-, medium- and less- consumption represented by Angaraeris rhodopa, Euchorthip-pus cheui and Chorthippus dubius respectively. The proportion of compound population density per square meter to grass consumption (kg)was determined as 1 : 16. 4732, and the regression equation reflecting the relationship between that density (x) and yield loss rate of grass was derived as y=-20. 8070+14. 4143x±15. 56 (r = 0. 9993, F>F0.01) According to the two results mentioned above, the action thresholds were obtained as 21. 7 and 26. 2 grasshopper no. / square meter respectively, and both the economic tolerant yield loss rates were 8. 8%. The action thresholds of single species belonged to the three consumption types were 5. 2(more consumption) ,17. 6(medium consumption)and 32. 3(less consumption)grasshopper no. /square meter.