Departamento de Entomologia e Acarologia, ESALQ-USP, Piracicaba, SP, Brazil.
Exp Appl Acarol. 2011 May;54(1):21-32. doi: 10.1007/s10493-011-9426-8. Epub 2011 Jan 29.
The two-spotted spider mite, Tetranychus urticae Koch, is an important pest of tomato in different parts of the world. Biological control of this pest on this crop has not been very successful. Phytoseiulus macropilis (Banks) has been used commercially for the control of T. urticae on different crops, but no information has been published on its potential to control T. urticae on tomato. The objective of this work was to compare the performance of a Brazilian population of P. macropilis on tomato with its performance on other plant species, relating the observed variation to the respective types and densities of trichomes. It has been hypothesized that the presence of the webbing produced by T. urticae could help the predator to avoid contact with trichomes and consequently to improve its performance on tomato plants. This hypothesis was also evaluated. Phytoseiulus longipes Evans was included in the work as a control, given that it has been reported to be a promising predator of Tetranychus species on tomato. The study was conducted under laboratory conditions. It was found that the performance of P. macropilis was similar to that of P. longipes and that trichomes hampered the locomotion as well as prey consumption and oviposition rate of both predators; that the presence of webbing resulted in higher levels of prey consumption and of predator oviposition; and that the presence of webbing eliminated the negative effect of trichomes of eggplants and partially eliminated the negative effect of trichomes of the 'cerasiforme' tomato variety. The observed density of trichomes in 'Carmem' one of the most common tomato varieties grown in Brazil, seems not to have interfered significantly with the prey consumption and the oviposition rate of P. macropilis. The results suggest that the latter is a promising predator of T. urticae on tomato. Complementary studies are warranted, to further evaluate the potential of P. macropilis for use as a biological control agent of this pest.
二斑叶螨（Tetranychus urticae Koch）是世界不同地区番茄的重要害虫。这种害虫的生物防治在这种作物上并不十分成功。巴氏新小绥螨（Phytoseiulus macropilis（Banks））已被商业化用于防治不同作物上的 T. urticae，但关于其控制番茄上 T. urticae的潜力尚未有报道。本工作的目的是比较巴西巴氏新小绥螨种群在番茄上的表现与其在其他植物物种上的表现，将观察到的变化与相应的类型和密度的刚毛相关联。有人假设，T. urticae 产生的网有助于捕食者避免与刚毛接触，从而提高其在番茄植株上的表现。该假设也进行了评估。长毛钝绥螨（Phytoseiulus longipes Evans）被包括在工作中作为对照，因为它已被报道是番茄上的 Tetranychus 物种的有前途的捕食者。该研究是在实验室条件下进行的。结果发现，巴氏新小绥螨的表现与长毛钝绥螨相似，刚毛阻碍了两种捕食者的运动以及猎物的消耗和产卵率；网的存在导致了更高的猎物消耗和捕食者的产卵率；网的存在消除了茄子刚毛的负面影响，并部分消除了“cerasiforme”番茄品种刚毛的负面影响。在巴西种植的最常见的番茄品种之一“Carmem”中观察到的刚毛密度似乎没有对巴氏新小绥螨的猎物消耗和产卵率产生重大影响。结果表明，后者是番茄上 T. urticae 的有前途的捕食者。需要进行补充研究，以进一步评估巴氏新小绥螨作为该害虫生物防治剂的潜力。
