文章标题：AMF Inoculation Can Enhance Yield of Transgenic Bt Maize ａnd Its Control Efficiency Against Mythimna separata Especially Under Elevated CO2
影响因子：5.754
期刊：Frontiers in Plant Science
作者列表：Wang Long, Wang Xiaohui, Gao Fanqi, Lv Changning, Li Likun, Han Tong, Chen Fajun
发表时间：2021-6-8
DOI:10.3389/fpls.2021.655060
主要研究成果：The promotion ａnd application of transgenic Bt crops provides an approach for the prevention ａnd control of target lepidopteran pests ａnd effectively relieves the environmental pressure caused by the massive usage of chemical pesticides in fields. However, studies have shown that Bt crops will face a new risk due to a decrease in exogenous toxin content under elevated carbon dioxide （CO2） concentration, thus negatively affecting the ecological sustainability of Bt crops. Arbuscular mycorrhizal fungi （AMF） are important beneficial microorganisms that can effectively improve the nutrient status of host plants ａnd are expected to relieve the ecological risk of Bt crops under increasing CO2 due to global climate change. In this study, the Bt maize ａnd its parental line of non-transgenic Bt maize were selected ａnd inoculated with a species of AMF （Funneliformis caledonium, synonyms: Glomus caledonium）, in order to study the secondary defensive chemicals ａnd yield of maize, ａnd to explore the effects of F. caledonium inoculation on the growth, development, ａnd reproduction of the pest Mythimna separata fed on Bt maize ａnd non-Bt maize under ambient carbon dioxide concentration （aCO2） ａnd elevated carbon dioxide concentration （eCO2）. The results showed that eCO2 increased the AM fungal colonization, maize yield, ａnd foliar contents of jasmonic acid （JA） ａnd salicylic acid （SA）, but decreased foliar Bt toxin content ａnd Bt gene expression in Bt maize leaves. F. caledonium inoculation increased maize yield, foliar JA, SA contents, Bt toxin contents, ａnd Bt gene expression in Bt maize leaves, ａnd positively improved the growth, development, reproduction, ａnd food utilization of the M. separata fed on non-Bt maize. However, F. caledonium inoculation was unfavorable for the fitness of M. separata fed on Bt maize, ａnd the effect was intensified when combined with eCO2. It is indicated that F. caledonium inoculation had adverse effects on the production of non-Bt maize due to the high potential risk of population occurrence of M. separata, while it was just the opposite for Bt maize. Therefore, this study confirms that the AMF can increase the yield ａnd promote the expression levels of its endogenous （JA, SA） ａnd exogenous （Bt toxin） secondary defense substances of Bt maize under eCO2, ａnd finally can enhance the insect resistance capacity of Bt crops, which will help ensure the sustainable utilization ａnd safety of Bt crops under climate change.
