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Natural rubber is an important national strategic and industrial raw material. The leaf anthracnose of rubber trees caused by the Colletotrichum species is one of the important factors restricting the yields of natural rubber. In this study, we isolated and identified strain Bacillus velezensis SF334, which exhibited significant antagonistic activity against both C. australisinense and C. siamense, the dominant species of Colletotrichum causing rubber tree leaf anthracnose in the Hainan province of China, from a pool of 223 bacterial strains. The cell suspensions of SF334 had a significant prevention effect for the leaf anthracnose of rubber trees, with an efficacy of 79.67% against C. siamense and 71.8% against C. australisinense. We demonstrated that SF334 can lead to the lysis of C. australisinense and C. siamense mycelia by causing mycelial expansion, resulting in mycelial rupture and subsequent death. B. velezensis SF334 also harbors some plant probiotic traits, such as secreting siderophore, protease, cellulase, pectinase, and the auxin of indole-3-acetic acid (IAA), and it has broad-spectrum antifungal activity against some important plant pathogenic fungi. The genome combined with comparative genomic analyses indicated that SF334 possesses most genes of the central metabolic and gene clusters of secondary metabolites in B. velezensis strains. To our knowledge, this is the first time a Bacillus velezensis strain has been reported as a promising biocontrol agent against the leaf anthracnose of rubber trees caused by C. siamense and C. australisinense. The results suggest that B. velezensis could be a potential candidate agent for the leaf anthracnose of rubber trees. [ABSTRACT FROM AUTHOR]

Transcription activator-like effectors (TALEs) are proteins produced by plant pathogenic Xanthomonas spp. TALEs exhibit a conserved structure and have the ability to directly bind to the promoter region of host target genes where they activate transcription. TALEs in Xanthomonas oryzae pv. oryzae (Xoo), the causal agent of bacterial blight (BB) in rice, play important roles in triggering resistance (ETI) and susceptibility (ETS) for rice immunity. This review briefly describes rice resistance breeding in China, TALE properties and their roles, BB resistance (R) and susceptibility (S) genes in rice, the arms-race between TALEs and TALE-targets, and strategies for breeding disease-resistant crops. A systematic overview of the complex roles of TALEs are presented along with ongoing efforts to breed crops with durable and broad-spectrum resistance to the pathogenic bacterium. [ABSTRACT FROM AUTHOR]