【摘要】 室内采用叶碟饲养的方法研究了苹果园塔六点蓟马Scolothripstakahashii各发育阶段对山楂叶螨Tetranychusviennensis各虫态的功能反应,结果表明,塔六点蓟马成虫、幼虫对叶螨的卵、幼若螨及成螨的功能反应均为Holling-Ⅱ型;随着蓟马个体的不断生长,其捕食量逐渐增大,雌成虫的捕食量显著大于雄虫,但其捕食的猎物数量随着叶螨个体的不断生长而减少;温度对蓟马成虫的功能反应有明显的影响,在20~35℃范围内,随着温度的升高其处置时间缩短、捕食能力明显增强;蓟马成虫的日龄对其功能反应也有明显影响,雌虫在日龄在12d之后,捕食能力逐渐减弱,15d日龄的雌虫对螨卵的处置时间显著长于3~6d日龄,雄虫则在9d日龄时对螨卵的处置时间已显著延长。更多还原

【Abstract】 Scolothrips takahashii Prisener is an important specialized predator of hawthorn spider mite, Tetranychus viennensis Zacher, a damaging pest in apple orchard in Northern China. In this study, a leaf disc bioassay was used to examine the functional response of each active stage of the predatory thrips against the spider mite under the conditions of (25±1)℃, RH 60%±10%, and a photoperiod of 16L:8D; the influences of temperature and age of adult thrips on the functional response were also investigated at different level of constant temperatures and prey densities. Logistic regression was used to determine the type of functional response and Roger’s random predator equation to fit the experimental data; then a non-linear regression, i.e. Gause-Newton, was used to estimate and compare the attack rates and handling times among different treatments.The results indicated that functional responses of the thrips, including 1 st larvae, 2 nd larvae, female and male adults against each stage of the spider mite belonged to Holling-Ⅱtype. The number of prey killed by the thrips increased hyperbolically with increasing prey densities in each trial. Handling time (Th) estimates for the thrips decreased as the mite developed and increased with the development of thrips themselves, e.g. the Th of female adults of S. takahashii preying on eggs, larvae, protonymphs, deutonymphs, and females adult of T. viennensis were 0.4031, 0.6066, 0.7622, 1.0829, and 1.4524h, respectively, but when eggs of the mites were offered as prey, the Th of the thrips decreased from 2.779 h in 1 st larvae to 0.403 h and 1.2660 h in females and males respectively. There was no significant difference in the attack rates (a) among various stages of the thrips due to the overlaps of their associated 95% confidence interval, but significant differences were recorded in the handling times. In other wards, the smaller the prey, the shorter the handling times. Handling times in female thrips were significant shorter than that of males, indicating that female thrips were more voracious than males. The maximum predation of the spider mite eggs by females and males of the thrips were 59.81 and 23.19, respectively. The analysis showed that temperature had significant effects on the predatory capacity of adult thrips over the range of 20～35℃. The values of a in both males and females were significantly lower at 20℃ than at 25～35℃. The handling times in both males and females decreased linearly with increasing temperatures. Based on these results, a temperature vs handling time model was developed and parameterized. That is, Th=1.1438-0.0261x for females,and Th=2.405-0.056x for males (x is temperature), suggesting that the thrips would spend more time to handle the mite when temperature is low. Age of adult thrips imposed significant impacts on the functional response of S. takahashii attacking T. viennensis eggs. There was no significant difference in attack rates in both females and males among various ages tested, but obviously prolonged handling times were noted in both females aged 15 d or more and males aged 9 d or more,compared to that of 3-6 days old thrips. It was suggested that the ageing rate in males was faster than that in females.更多还原