不同葫芦科作物对二斑叶螨的抗性评价

Resistance of different cucurbit crops to Tetranychus urticae Koch

【目的】二斑叶螨Tetranychus urticae Koch是世界性重大农业害螨,葫芦科作物是其重要寄主植物。为明确不同葫芦科作物对二斑叶螨生长发育的抗性/适合性,开展了二斑叶螨在葫芦科作物上的产卵和取食选择性研究。【方法】选择苦瓜、葫芦、南瓜、丝瓜、西瓜、甜瓜和黄瓜作为供试寄主植物,室内采用离体叶片和室外采用活体植株比较了二斑叶螨对7种作物的取食选择性及其种群生存与繁殖动态。【结果】供试7种葫芦科作物中,二斑叶螨对黄瓜的选择率最高,为35.49%,其次为甜瓜和西瓜;二斑叶螨在南瓜和黄瓜叶碟上的生存率和繁殖率高,12 h单雌产卵数分别为9.72粒和7.83粒;在葫芦和苦瓜叶碟上,二斑叶螨48 h螨口减退率达47.5%和32.5%,表现为较低的取食和生存适合度,同时葫芦和苦瓜活体植株上二斑叶螨繁殖率显著低于其他5种葫芦科作物。【结论】二斑叶螨在黄瓜、西瓜和甜瓜上的种群发育适合度高,在葫芦和苦瓜上适合度低。这一结果可为田间防控二斑叶螨生态措施的制定及开展葫芦科作物抗螨性机理和抗螨育种提供科学依据。

[Objectives]To determine the resistance of different cucurbit crops to the two-spotted spider mite,Tetranychus urticae Koch,a major global pest of the cucurbitaceae.[Methods]The preference,survival and reproductive dynamics of T.urticae on bitter gourd,calabash,pumpkin,towel gourd,watermelon,melon and cucumber,were measured and compared using the leaf disc method in the laboratory and in field trials.[Results]Cucumbers were the most preferred crop(35.49%),followed by melons and watermelons.T.urticae had a higher survival and reproductive rate on the leaf discs of pumpkins and cucumbers,laying 9.72 and 7.83 eggs per female within 12 h,respectively.The abundance of T.urticae had reduced by 47.5%and 32.5%after 48 h on leaf discs of calabash and bitter gourd,respectively,indicating lower preference for,and survival on,these crops.The reproductive rate of T.urticae on calabash and bitter gourd was also significantly lower than on the other 5 cucurbit crops.[Conclusion]T.urticae has higher fitness on the leaves of cucumber,watermelon and melon than on those calabash and bitter gourd.These findings provide a scientific basis for developing ecological strategies to control this pest in the field,research on mite-resistance mechanisms in the cucurbitaceae and breeding mite-resistant cucurbit cultivars.