Influences Of Interactive Feeding On Chinese Kale On Biological Characteristics Of Plutella Xylostella And Bemisia Tabaci

Bemisia tabaci?Gennadius?and Plutella xylostella?L.?are important cosmopolitan pests,which often co-occur in field.In order to clarify the influences of interactive feeding on Chinese cale on biological characteristics of P.xylostella and B.tabaci,the Age-stage,two-sex life table?TWOSEX?was used to study the influence of induced defenses by different infestation order of B.tabaci and P.xylostella on their biology when they fed on Chinese kale.The main results were listed:The induced response on Chinese kale caused by pre-feeding of P.xylostella shortened the development duration of B.tabaci nymphs,improved the uniformity of nymph development and increased the survival rate of 4th instar whitefly nymphs by 21.2%.The net reproductive rate?R₀?and the finite rate of increase???both increased significantly,and the peak value of the fecundity curve of the population increased by 8.7%,and the fecundity increased by 76.4%.When P.xylostella and B.tabaci were fed together,the survival rate of the 2-3th instar nymphs,oviposition days,fecundity and R₀ of B.tabaci increased significantly,with the female adult longevity expended by 77.8%,the life expectancy extended by 57.8%.Population Projection shows that the cohort size of B.tabaci which developed on P.xylostella pre-fed Chinese kale after two generations reached more than 10 times compared to the control.The induced response on Chinese kale caused by pre-feeding of B.tabaci reduced the development uniformity of P.xylostella larvae,pre-adult survival rate,shortened the oviposition days and made the peak values of fecundity curves and female reproduction value curves decrease by 22.7%and 19.1%,respectively.When B.tabaci and P.xylostella fed simultaneously,the peak values of life expectancy and fecundity curves of P.xylostella were decreased,the larval development duration was shortened,but the fecundity of females increased by 74.9%compared to the treatment which B.tabaci pre-fed.The peak values of cumulative age-specific net maternity curve and female reproductive value curve increased by 32.2%and 6.7%,respectively.Regardless of whether the B.tabaci damage was caused first or at the same time,the population parameters of the P.xylostella population,r,R₀,?and T,had no significant difference.Population Projection shows that t he cohort size of P.xylostella which developed on B.tabaci co-fed Chinese kale after two generations expended nearly 100 times compared to the control.The results of this study revealed a strong asymmetry effect between the pests populations related to the colonization order,which is particularly evident when the two pests colonize in sequence.This result can help us better understand the interaction between pests meditated by tritrophic interactions,and can also provide new ideas for us to find comprehensive prevention and control methods in the future.