Penoxsulam-resistant barnyardgrass-mediated rhizosphere microbial communities affect the growth of rice

BACKGROUNDThe incidence of herbicide-resistant barnyardgrass is escalating in paddy fields, yet the interactions between resistant weeds and rice are largely unknown. The microbiota of herbicide-resistant barnyardgrass rhizosphere soil is critical for both barnyardgrass and rice fitness. RESULTSRice has different biomass allocation and root traits in the presence of penoxsulam-resistant versus penoxsulam-susceptible barnyardgrass or in their conditioned soil. Compared to susceptible barnyardgrass, resistant barnyardgrass led to an allelopathic increase in rice root, shoot, and whole-plant biomasses. Resistant barnyardgrass recruited distinct core and unique microbes in rhizosphere soil compared to susceptible barnyardgrass. In particular, resistant barnyardgrass assembled more Proteobacteria and Ascomycota to enhance plant stress tolerance. Furthermore, the root exudates from resistant and susceptible barnyardgrass were responsible for the assembly and establishment of the root microbial structure. Importantly, (-)-loliolide and jasmonic acid in root exudates were correlated with the core microbes in the rhizosphere soil. CONCLUSIONThe interference of barnyardgrass with rice can be mediated by rhizosphere microbial communities. Biotype-specific variation in the ability to generate soil microbial communities appears to ameliorate the negative consequences for rice growth, providing an intriguing possibility for modulation of the rhizosphere microbiota to increase crop productivity and sustainability. (c) 2023 Society of Chemical Industry.

Automated summary

The interaction between herbicide-resistant barnyardgrass and rice is mediated by rhizosphere microbial communities. Resistant barnyardgrass recruits specific bacteria and fungi to enhance its stress tolerance, and the root exudates of barnyardgrass are correlated with the core microbes in rice rhizosphere soil. Modulating the rhizosphere microbiota may improve rice growth, increase crop productivity, and ensure sustainability.