High nitrogen in maize enriches gut microbiota conferring insecticide tolerance in lepidopteran pest Spodoptera litura
Lin Hu,
Zhongxiang Sun,
Cuicui Xu,
Jie Wang,
Azim U. Mallik,
Chengzhen Gu,
Daoqian Chen,
Long Lu,
Rensen Zeng,
Yuanyuan Song
Affiliations
Lin Hu
Key Laboratory of Ministry of Education for Genetics, Breeding and Multiple Utilization of Crops, College of Agriculture, Fujian Agriculture and Forestry University, Fuzhou 350002, China; Key Laboratory of Beibu Gulf Environment Change and Resources Utilization of Ministry of Education, Nanning Normal University, Nanning 530001, China
Zhongxiang Sun
Key Laboratory of Ministry of Education for Genetics, Breeding and Multiple Utilization of Crops, College of Agriculture, Fujian Agriculture and Forestry University, Fuzhou 350002, China
Cuicui Xu
State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, College of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou 350002, China
Jie Wang
Key Laboratory of Ministry of Education for Genetics, Breeding and Multiple Utilization of Crops, College of Agriculture, Fujian Agriculture and Forestry University, Fuzhou 350002, China
Azim U. Mallik
Department of Biology, Lakehead University, Thunder Bay, ON P7B 5E1, Canada
Chengzhen Gu
State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, College of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou 350002, China
Daoqian Chen
Key Laboratory of Ministry of Education for Genetics, Breeding and Multiple Utilization of Crops, College of Agriculture, Fujian Agriculture and Forestry University, Fuzhou 350002, China
Long Lu
Key Laboratory of Ministry of Education for Genetics, Breeding and Multiple Utilization of Crops, College of Agriculture, Fujian Agriculture and Forestry University, Fuzhou 350002, China
Rensen Zeng
Key Laboratory of Ministry of Education for Genetics, Breeding and Multiple Utilization of Crops, College of Agriculture, Fujian Agriculture and Forestry University, Fuzhou 350002, China; State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, College of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou 350002, China
Yuanyuan Song
Key Laboratory of Ministry of Education for Genetics, Breeding and Multiple Utilization of Crops, College of Agriculture, Fujian Agriculture and Forestry University, Fuzhou 350002, China; Corresponding author
Summary: Abuse of chemical fertilizers and insecticides has created many environmental and human health hazards. We hypothesized that high nitrogen (N) in crops changes insect gut microbiota leading to enhanced insecticide tolerance. We investigated the effect of high N in maize on gut microbiota and insecticide tolerance of the polyphagous pest Spodoptera litura. Bioassays showed that high N applied in both maize plants and artificial diets significantly enhanced larval growth but reduced larval sensitivity to the insecticide methomyl. High N promoted the gut bacterial abundance in the genus Enterococcus. Inoculation with two strains (E. mundtii and E. casseliflavus) isolated from the larval guts increased larval tolerance to methomyl. Incorporation of antibiotics in a high-N diet increased the larval sensitivity to methomyl. These findings suggest that excessive application of N fertilizer to crops can increase insecticide tolerance of insect pests via changing gut microbiota, leading to increased use of insecticides worldwide.
