Ma Junchi, Chen Jili, Zhang Qing, Dong Yumei, Li Zhihua, Xie Junqiu, Yang Dongmei, Zhou Lequn, Yan Dahao, Zhou Bo, Liu Tao
College of Agronomy and Biotechnology, Yunnan Agricultural University, Kunming, China.
Tobacco Leaf Quality Inspection Section, Raw Material Department, Hongyun Honghe Tobacco (Group) Co., Ltd., Kunming, China.
Front Microbiol. 2024 Oct 23;15:1428284. doi: 10.3389/fmicb.2024.1428284. eCollection 2024.
There is a close and complex interaction between the elements in the aboveground-underground ecosystem during the growth and development of plants. Specifically, when the aboveground part of plants is infected by pathogens, it induces the plant rhizosphere to synthesize specific root exudates. Consequently, a group of beneficial rhizosphere soil bacteria is recruited to help plants resist diseases. However, the changes in the rhizosphere soil bacterial community of plants under infection by oomycete pathogens remain unknown.
Three experimental treatments were set up in this experiment: soils inoculated with , no-inoculation with , and a control. The control treatment was composed of soils without transplanted tobacco plants, with the pathogen inoculated twice at an interval of eight days to ensure a successful infection. inoculation treatments were designed using the hyphal block inoculation method. In the non-inoculation treatment, tobacco plants were grown normally without pathogen inoculation. The tobacco plants were grown in a greenhouse.
This study demonstrates that tobacco plants recruit microorganisms at the rhizosphere level as a defense mechanism against disease after infection by the oomycete pathogen . Specific rhizosphere soil bacteria were screened to promote tobacco growth in a biofilm-forming manner, which induced the systemic resistance of the plants to . The recruitment of rhizosphere soil bacteria to the inter-root zone of tobacco plants after infection by can help subsequently cultivated tobacco plants in the same soil resist pathogen infestation.
In conclusion, the present study confirms that infestation caused by oomycete pathogens alters the composition of the plant rhizosphere soil bacterial community and recruits a specific group of beneficial microorganisms that induce disease resistance and promote plant growth, thereby maximizing the protection of progeny grown in the same soil against the disease.
在植物生长发育过程中，地上-地下生态系统中的各要素之间存在着紧密而复杂的相互作用。具体而言，当植物地上部分受到病原体感染时，会诱导植物根际合成特定的根系分泌物。因此，会招募一组有益的根际土壤细菌来帮助植物抵御疾病。然而，卵菌病原体感染下植物根际土壤细菌群落的变化仍不清楚。
本实验设置了三种实验处理：接种土壤、未接种土壤和对照。对照处理由未移栽烟草植株的土壤组成，每隔八天接种两次病原体以确保成功感染。接种处理采用菌丝块接种法设计。在未接种处理中，烟草植株正常生长，不接种病原体。烟草植株在温室中生长。
本研究表明，烟草植株在受到卵菌病原体感染后，会在根际水平招募微生物作为抵御疾病的防御机制。筛选出特定的根际土壤细菌以生物膜形成的方式促进烟草生长，从而诱导植物对该病原体的系统抗性。烟草植株感染该病原体后，根际土壤细菌向根际间区域的募集有助于后续在同一土壤中种植的烟草植株抵抗病原体侵染。
总之，本研究证实卵菌病原体侵染会改变植物根际土壤细菌群落的组成，并招募一组特定的有益微生物，这些微生物可诱导抗病性并促进植物生长，从而最大程度地保护在同一土壤中生长的后代免受该疾病侵害。
