Cry Toxin from Bacillus thuringiensis: Research Status

doi:10.11924/j.issn.1000-6850.casb2023-0507

Abstract

Abstract:

Bacillus thuringiensis (Bt) is the most successful microbial insecticide in application. The largest class of insecticidal proteins produced by Bt is Cry toxin, and its application in field is an important means for controlling agricultural pests and increasing crop yields. Cry toxin has the advantages of quick-acting at host organisms, low impact on non-target organisms, environmental friendliness and degradability. This study briefly describes the research on insect resistance caused by Cry toxin when it is put into agricultural use. The research status of structure and function, mechanism of action, protein domain and insect resistance of Cry toxin are summarized. The three main features of the promotion of insect resistance by epigenetic mechanism, receptor regulation and native intestinal flora are concluded. The Countermeasures against resistant insects are analyzed. It is considered that artificial selection of new resistant insects can predict possible resistance pathways, and directional evolution of Cry toxin and interactive use strategy in field are the research priorities. The paper is aimed to provide theoretical basis for successful application of Cry toxin in agricultural biological control.

Key words: biological control, Cry toxin, insect resistance, insecticidal mechanism, catastrophic transformation

FU Baiwen, XU Lian, ZHENG Meixia, ZHU Yujing. Cry Toxin from Bacillus thuringiensis: Research Status[J]. Chinese Agricultural Science Bulletin, 2024, 40(5): 88-96.

Figures/Tables 1

References 107

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