不同地理种群草间钻头蛛（Hylyphantes graminicola）对杀虫剂的敏感性及抗、感种群的相对适合度

采用成蛛浸渍法测定了湖北武汉、湖北来凤、陕西渭南和山东菏泽4个草间钻头蛛地理种群对氰戊菊酯、溴氰菊酯、辛硫磷和甲胺磷4种杀虫剂的敏感性。结果表明：湖北武汉和山东菏泽草间钻头蛛种群对4种杀虫剂的抗药性都较小，处于敏感水平，陕西渭南、湖北来凤种群对甲胺磷和辛硫磷的抗性达到了中抗水平。4个种群对溴氰菊酯和氰戊菊酯均未产生抗药性，说明拟除虫菊酯类杀虫剂对草间钻头蛛的毒力要大于有机磷类杀虫剂。在测定了蜘蛛对不同杀虫剂敏感水平的基础上，以陕西渭南种群为抗性种群（R），湖北武汉种群为敏感种群（S），比较研究了这2个种群的生物学特性和相对适合度。结果表明两种群在发育历期和成活率上无显著差异。在繁殖力方面，R种群产卵率、产卵量和孵化率均明显下降。R种群的相对适合度为0．74，对有机磷产生抗性的草间钻头蛛种群存在繁殖不利性。

Susceptibility to pesticides of different geographic populations of Hylyphantes graminicola and relative fitness of susceptible and resistant populations

Samples from populations of Hylyphantes graminicola(Araneae:Linyphiidae)were collected from Wuhan(WH)(Hubei Province),Laifeng(LF)(Hubei Province),Weinan(WN)(Shanxi Province)and Heze(HZ)(Shandong Province)in China and their susceptibility to fenvalerate,deltamathrin,phoxin and methamidophos were investigated using dipping methods.The results showed that the populations of H.graminicola from Wuhan and Heze were susceptible to 4 species of insecticides,and those from Weinan and Laifeng had developed middle levels of resistance to phoxin and methamidophos.All four populations were susceptible to fenvalerate and deltamathrin,It indicated that pyrethroids had a high toxicity to H.graminicola than organophosphates.The biology and reproduction of the Weinan(resistant)population and Wuhan(susceptible)population were carefully observed and relative fitness was determined by net reproductive rate(R0).The results showed that resistant population suffered reproductive disadvantages including having lower mean fecundity and a decrease in oviposition and hatching rates.No developmental defect was observed in resistant population.Resistant population was calculated to have a fitness value of 0.74 relative to susceptible population.