Department of Zoology, Jomo Kenyatta University of Agriculture and Technology, PO Box 62000-00200, Nairobi, Kenya.
Exp Appl Acarol. 2011 Aug;54(4):385-93. doi: 10.1007/s10493-011-9446-4. Epub 2011 Apr 11.
The spider mite Tetranychus evansi has a broad range of host plants. Control of T. evansi has been a big challenge to tomato farmers due to its fast rate of reproduction, development of resistance to chemical pesticides and its ability to use weeds as alternative hosts when the tomato plants are not available. The aim of the current study was to determine the host plant acceptance and the relative contributions of trichomes in the control of the red spider mite by comparing the survival, development and oviposition rates of the red spider mite on eight tomato accessions. Leaflets from eight tomato varieties were assayed with the spider mites to determine the egg laying capacity and developmental time of the spider mites on the tomato accessions as well as the trichome densities. Densities of trichome types I, IV, V and VI varied among the tomato accessions. Variation in types I, IV and VI accounted for most of the variation in mite responses. The varieties with high densities of types IV and VI had the highest fecundity and mite development did not go beyond the larval stage. The developmental time varied significantly among the tomato accessions. The results indicated that the higher the density of trichome type I the lower the adult survival. The findings indicated possible resistance of some of the tested tomato accessions against T. evansi which is partially associated with trichomes types and density.
叶螨 Tetranychus evansi 有广泛的宿主植物。由于其繁殖速度快、对化学农药产生抗药性以及在番茄植株不可用时能够利用杂草作为替代宿主，因此控制叶螨对番茄种植者来说是一个巨大的挑战。本研究的目的是通过比较 8 种番茄品系上红蜘蛛的存活率、发育和产卵率，确定宿主植物的接受程度和毛状体在控制红蜘蛛中的相对贡献。用叶螨检测 8 个番茄品种的小叶，以确定叶螨在番茄品系上的产卵能力和发育时间以及毛状体密度。番茄品系之间的毛状体类型 I、IV、V 和 VI 的密度存在差异。I 型、IV 型和 VI 型的变异解释了大多数螨类反应的变异。IV 型和 VI 型密度较高的品种具有最高的繁殖力，并且螨虫的发育不会超过幼虫阶段。番茄品系之间的发育时间差异显著。结果表明，毛状体类型 I 的密度越高，成虫的存活率越低。研究结果表明，一些被测试的番茄品系可能对 T. evansi 具有抗性，这部分与毛状体类型和密度有关。
