Transgenic Bacillus thuringiensis (Bt) maize has broad prospects for application in China. Before commercialization, it is necessary to assess possible ecological impacts, including impacts on non-target arthropods (NTAs) in the field. In the present study, transgenic Bt maize expressing cry1Ab/2Aj and its corresponding non-transformed near isoline were planted under the same environmental and agricultural conditions, and arthropods in the field were collected during the three main growth stages of maize. In a one year trial, the results showed the composition of NTA communities in the transgenic and control maize fields were similar. There were no significant differences for community-level parameters of species richness (S), Shannon–Wiener diversity index (H′), evenness index (J) and Simpson’s dominant concentration (C) between the two types of maize fields. Likewise, a Bray–Curtis dissimilarity and distance analysis showed that Cry1Ab/2Aj toxin exposure did not increase community dissimilarities between Bt and non-Bt maize plots and that the structure of the NTAs community was similar on the two maize varieties. Furthermore, planting of the transgenic cry1Ab/2Aj maize did not affect the density or composition of non-target decomposers, herbivores, predators, parasitoids and pollinator guilds. In summary, our results showed that planting of Bt maize producing Cry1Ab/Cry2Aj proteins do not adversely affect population dynamics and diversity of NTAs.

Summary Herbivore‐induced plant volatiles (HIPVs) are known to be perceived by neighboring plants, resulting in induction or priming of chemical defenses. There is little information on the defense responses that are triggered by these plant–plant interactions, and the phenomenon has rarely been studied in rice. Using chemical and molecular analyses in combination with insect behavioral and performance experiments, we studied how volatiles emitted by rice plants infested by the striped stemborer (SSB) Chilo suppressalis affect defenses against this pest in conspecific plants. Compared with rice plants exposed to the volatiles from uninfested plants, plants exposed to SSB‐induced volatiles showed enhanced direct and indirect resistance to SSB. When subjected to caterpillar damage, the HIPV‐exposed plants showed increased expression of jasmonic acid (JA) signaling genes, resulting in JA accumulation and higher levels of defensive proteinase inhibitors. Moreover, plants exposed to SSB‐induced volatiles emitted larger amounts of inducible volatiles and were more attractive to the parasitoid Cotesia chilonis. By unraveling the factors involved in HIPV‐mediated defense priming in rice, we reveal a key defensive role for proteinase inhibitors. These findings pave the way for novel rice management strategies to enhance the plant's resistance to one of its most devastating pests.

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