Ecological and evolutionary conseguences of diapause in the interactive system between tetranychid mites and their predators

本文研究了叶螨及其捕食性天敌沃氏钝绥螨滞育特性的变化，并阐明了这种变化对叶螨与沃氏钝绥螨互作系统的生态学和进化意义.叶螨，特别是二斑叶螨的种间和种内变异较大。二斑叶螨滞育受多基因控制，其表达受温度影响较大.华氏蒿滞育强度也有较大的变化。滞育率存在纬度梯度，北方种群在<18 ℃ 9 L15 D时滞育率接近100%，而冲绳种群在15 ℃时仍有许多个体不进入滞育.研究了滞育强度与产卵量的关系 关于我们 率在A. womersleyi的寄生种群。滞育强度高的种群在高温下的繁殖率高于低温，滞育强度弱的种群的产卵率不受温度的影响，即使在低温下也有较高的产卵率.比较了中纬度地区相同生境下中华绒螯螨和中华绒螯螨滞育特征之间的关系。叶螨的滞育在种间和种内都表现出很大的差异，而沃氏叶螨的滞育特征与其猎物种类无关，差异很小。因此，没有发现明显的关系，表明猎物物种的物候不是决定捕食者滞育特征的主要选择力。叶螨与植绥螨的相互作用系统往往很不稳定。为了维持植绥螨的种群数量，捕食者维持种群内滞育属性的变化比严格根据猎物的滞育特征进化滞育策略更有利。少

We studied the variations in diapause characterisitics in tetranychid mites and their phytoseiid predator, Amblyseius womersleyi, and elucidated the ecological and evolutionary significance of the variations to the interactive system between them.1. Wide inter-and intra-spesific variations were observed in tetranychid mites, especially in Tetranychus urticae. The diapause of T.urticae was under polygenic control, and its expression was affected greatly by temperature.2. A.womersleyi had also large variations in diapause intensity. The percentage of diapause showed a latitudinal cline : northern populations showed nearly 100% of diapause at <18ﾟC9L15D,whereas many individuals in populations from Okinawa did not enter diapsue even at 15ﾟC.The diapause expression in populations from intermediate latitudes depended greatly on temperature, and the percentage of diapause decreased with increasing temperature.3. We studied the relationship between the intensity of diapause and the oviposition … More rate in seveal populations of A.womersleyi. Populations with high intensity of diapause had higher reproductive rates at higher than lower temperatures, whereas the oviposition rate in populations with very weak diapause was not affected by temperature and they had high oviposition rates even at low temperature ranges.4. We compared the relationship between the diapause characteristics of teranychid mites and A.womersleyi that occurred at the same habitats in intermediate latitudes. Tetranychid mites exhibited wide variations in diapause both between and within species, whereas A.womersleyi showed little variations irrespective of the diapause characteristics of their prey species. Thus, no clear relation was detected, showing that the phenology of the prey species is not the major selective force for determining the diapuse characteristics of the predator.5. The interactive system between tetranychid and phytoseiid mites often are very unstable. In order that phytoseiid mites maintain their populations, it will be more profitable for the predators to maintain variations in diapause attribute within their populations, than to evolve their diapause strategies strictly in response to the diapause characteristics of their prey. Less