Abstract:

Weeds are one of the most serious pests to agricultural production, and their control mainly depends on chemical herbicides. Long-term and large-scale use of chemical herbicides will lead to the increase of weed resistance, environmental security and food security. Microbial herbicides are biological herbicides developed by using microorganisms themselves or their metabolites, which are characterized by abundant resources, environmental friendliness, not easy to have resistant weeds, which are the development direction of green weed biocontrol in the world. In this paper, we summarized the types of microbial herbicides and listed the biocontrol microorganisms and toxins with herbicidal activity. Then, we reviewed the mechanism of microbial weed control. Microorganisms invaded the weed host through infection, causing the tube closure of the weed, and finally resulting in plant wilting and dying. In otherwise, they affected the cell structure integrity, biofilm function, lipid stability, energy transfer, photosynthetic pigment synthesis, lipid synthesis and amino acid synthesis of the weed host through effective active substances in metabolites, to achieve the purpose of killing weeds. In addition, we summarized the application status of microbial herbicides, including commercialization, constraints in application and improvement strategies of control effect; as well as the application of omics technology in the field of microbial herbicides. Finally, we prospected the development direction and application prospect of microbial herbicides，aiming to provide reference for the research and development of new herbicides.

Key words: herbicides, plant pathogen, metabolites, weeding mechanism