The isolation of the antagonistic strain Bacillus australimaris CQ07 and the exploration of the pathogenic inhibition mechanism of Magnaporthe oryzae

Abstract

Biological control as a promising method to combat plant disease has gained public attention in recent years. In the present study, we isolated 12 strains resistant to Magnaporthe oryzae from western Sichuan subalpine soil. Among them, CQ07 exhibited remarkable activity against M . oryzae . The result of 16S rRNA sequence analysis revealed that CQ07 is approximately 99% similar to Bacillus australimaris . The sterilized culture filtrate of CQ07 inhibited the growth of M . oryzae , which motivated us to deduce the influence of CQ07 on the pathogenicity of M . oryzae . As shown by experimentation, sterilized culture filtrate (10 μl/ml) of CQ07 can delay and even suppress the germination of conidia and prevent the formation of appressorium in vitro and in vivo. In addition, by simulative field tests, the spraying of conidia suspension diluted with sterilized culture filtrate of CQ07 reduced infection of rice blast. To better control rice blasts, understanding the infection mechanism of M . oryzae and inhibiting the mechanism of the antagonistic strain is of great importance.

Short Communication: Bacterial diversity of mangrove ecosystem in Klawalu Sorong, West Papua, Indonesia

“…These bacteria can grow on MRS media, as has been conducted in this study. Furthermore, B. australimaris can be used as a biocontrol, because it is able to inhibit the growth of the pathogen M. oryzae (Chen et al 2019). These bacteria also include lactic acid bacteria that can be used as probiotics and found in fermented food products (Cissé et al 2019).…”

The antagonistic mechanism of Bacillus velezensis ZW10 against rice blast disease: Evaluation of ZW10 as a potential biopesticide

“…The appressorium formation rate was calculated as follows: Formation rate of appressorium (%) = (B 1 / B 2 ) × 100%where B 1 = the number of conidia that formed appressorium and B 2 = the total number of conidia [25].…”

Antimicrobial and quorum sensing inhibitory activity of epiphytic bacteria isolated from the red alga Halymenia durvillei

“…safensis has been isolated from habitats that were relatively extreme for other micro-organisms to grow in. Such habitats include rhizospheres of plants, feather dumping sites, sediments from offshore oilfields, olive oil-contaminated soil, saline desert soil and explosive-contaminated soil [54–57]. Different strains of B.…”

“…Different strains of B. safensis have been shown to produce various enzymes that are important in many industrial applications, such as inulinases [57], proteases [56], keratinases [55], xylanases and pectinases [54]. In addition, the presence of oxidoreductases in B.…”