B和Q型烟粉虱是世界重要入侵性害虫。在中国，Q型烟粉虱逐渐取代B型而成为农田优势生物型，其确切取代机制目前所知甚少。我们前期研究发现，Q型烟粉虱较之B型烟粉虱在营养贫乏的寄主植物上表现更好。同时Q型烟粉虱具有更广的寄主范围，如辣椒和菜豆上，Q型烟粉虱生长发育良好，而B型烟粉虱很难存活，Q型烟粉虱可能对寄主抗虫物质耐受性更强。寄主受害虫侵染后诱导防御反应通常降低营养水平和升高次生抗虫物质含量，B和Q型烟粉虱对寄主防御反应耐受性差异也可能介导二者之间的竞争取代。据此我们推测：B和Q型烟粉虱对寄主营养水平和次生抗虫物质（组成型和诱导型）耐受性差异可能介导B和Q型烟粉虱间竞争取代。本研究以B和Q型烟粉虱及不同品种的辣椒和甘蓝为研究体系，比较不同品种寄主营养水平及次生抗虫物质对B和Q型烟粉虱取食和产卵、生长发育、繁殖和解毒酶表达及竞争取代的影响，从营养和和抗性生理角度阐明B和Q型烟粉虱竞争取代机制。

B and Q biotypes Bemisia tabaci are important invasive pests throughout the world. Q biotype B. tabaci in China is gradually replacing the B biotype and become the dominant biotype in field, however, we know little about its exact mechanisms underlying the competitive displacement of B by Q whitefly. Our previous studies found that Q whitefly performed better on the oligotrophic host plants compared with B whitefly. Q whitefly has a wider host range, Q whitefly could complete growth and development on some host plants, such as peppers and kidney beans, whereas B whitefly is difficult to survive on these plants. Q whitefly is more tolerant to the insect-resistant material derived from host plants than B whitefly. The defense responses of the host plants induced by pest infestation usually decrease host nutrient levels and increase the secondary insect-resistant material content, the tolerance differences between B and Q whitefly to host defense response may mediate the competitive displacement. We therefore speculated that the tolerance differences between B and Q whitefly to host nutrient levels and the secondary insect-resistant substances (constitutive and inducible) may mediate their competitive displacement. In the present study, we compare and determine the asymmetric effects of the nutrient levels and/or secondary insect-resistant substances derived from some pepper and cabbage cultivars differing in resistance to whitefly on B and Q feeding and oviposition, growth and development, reproduction and detoxification enzyme activity. From the perspective of host nutrition and resistance physiology, we aim to elucidate the underlying mechanisms of competitive displacement of B by Q whitefly.