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bioRxiv · 10.1101/2021.02.08.430243

Rapid spread of a symbiotic virus in a major crop pest following wide-scale adoption of Bt-cotton in China

Wu, K.·Xiao, Y.·Xu, P.·Wilson, K.·Bravo, A.·Soberon, M.·Yang, X.·Yuan, H.·Jin, M.·Zheng, W.·Li, W.
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Abstract

Bacillus thuringiensis (Bt) crops have been widely planted and the effects of Bt-crops on populations of the target and non-target insect pests were well studied. However, the effects of Bt-crops exposure on microorganisms that interact with crop pests havent previously been quantified. Here, we use laboratory and field data to show that infection of Helicoverpa armigera with a symbiotic densovirus (HaDV2) is associated with its enhanced growth and resistance to Bt-cotton. Moreover, field monitoring showed a much higher incidence of cotton bollworm infection with HaDV2 in regions cultivated with Bt-cotton than in regions without it, with the rate of densovirus infection increasing with increasing use of Bt-cotton. RNA-seq suggested resistance to both baculovirus and Cry1Ac were enhanced via the immune-related pathways. These suggest that the exposure to Bt-crops has selected for beneficial interactions between the target pest and a symbiotic microorganism that enhances its performance on Bt-crops under field conditions.

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Wu, K., Xiao, Y., Xu, P., Wilson, K., Bravo, A., Soberon, M., Yang, X., Yuan, H., Jin, M., Zheng, W., Li, W.. 2021-02-10. Rapid spread of a symbiotic virus in a major crop pest following wide-scale adoption of Bt-cotton in China. https://doi.org/10.1101/2021.02.08.430243

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