Abstract:
Biochar amendment is acknowledged to favor plant resistance against soil-borne diseases. Although plant-beneficial bacteria enrichment in the rhizosphere is often proposed to be associated with this protection, the mechanism behind this stimulating effect remains unelucidated. Here, we tested whether biochar promotes plants to recruit beneficial bacteria to the rhizosphere, and thus develop a disease-suppressive rhizosphere microbiome. In a pot experiment, biochar amendment decreased tomato Fusarium wilt disease severity. Using a transplanting rhizosphere microbiome experiment, we showed that biochar enhanced the suppressiveness of tomato rhizosphere microbiome against Fusarium wilt disease. High-throughput sequencing of 16S ribosomal RNA gene and in vitro cultures further indicated that the recruited suppressive rhizosphere microbiome was associated with the increase of plant-beneficial bacteria, such as Pseudomonas sp. This amendment also enhanced the in vitro chemoattraction and biofilm promotion activity of tomato root exudates. Collectively, our results demonstrate that biochar amendment induces tomato seedlings to efficiently recruit a disease-suppressive rhizosphere microbiome against Fusarium wilt.
摘要:
生物炭修正案被认为有利于植物对土壤传播疾病的抗性。尽管经常提出根际中植物有益细菌的富集与这种保护有关,这种刺激作用背后的机制仍未阐明。这里,我们测试了生物炭是否促进植物向根际招募有益菌,从而发展出抑制疾病的根际微生物组。在大麻实验中,生物炭改良降低了番茄枯萎病的严重程度。使用移植的根际微生物组实验,结果表明,生物炭增强了番茄根际微生物组对枯萎病的抑制作用。16S核糖体RNA基因的高通量测序和体外培养进一步表明,招募的抑制性根际微生物组与植物有益细菌的增加有关。如假单胞菌。该修正案还增强了番茄根系分泌物的体外化学吸引和生物膜促进活性。总的来说,我们的结果表明,生物炭改良诱导番茄幼苗有效地招募抑制枯萎病的根际微生物组。