International Journal of Applied Microbiology and Biotechnology Research
ISSN: 2053-1818
Vol. 8(3), pp. 21-30, August, 2020
doi.org/10.33500/ijambr.2020.08.003

Plant-derived allyl isothiocyanate enrich biocontrol microbes of tomato plant rhizosphere in vegetable greenhouse

Xiangmei Yao¹'³*, Zhijun Lu²'³, Cece Yin¹, Qiong Fu² and Jian Ye¹*.

¹State Key Laboratory of Plant Genomics, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China.
²Laboratory of Pests Detection, Beijing Plant Protection Station, Beijing, 100029, China.
³These authors contributed equally to this work.

*To whom correspondence should be addressed. E-mail: yaoxm@im.ac.cn, jianye@im.ac.cn.

Received 20 May, 2020; Received in revised form 17 June, 2020; Accepted 18 June, 2020.

Abstract

Keywords:
Allyl isothiocyanate, Rhizosphere microbiome, Bacterial community, Fungal community, Soil-borne diseases.

Natural plant-derived metabolites have been widely used for human nutrients, antitumor, antimicrobial agents. Glucosinolate is the most abundant secondary metabolites in the botanical order Brassicales. Recently allyl isothiocyanate (AITC) has been applied as a soil fumigant in greenhouse vegetable production to control soil-borne diseases. Although AITC is known to directly inhibit bacterial and fungal pathogens and nematodes, it is not clear if it could also enrich the beneficial microbes associated with soil. In this study, bacterial and fungal communities from AITC-treated soil, with- or without- tomato plants, were studied in a greenhouse vegetable production facility. Microbiome structures differed between the AITC-treated soil, with- or without- tomato plants. Fungal community diversity was significantly decreased in phylum and species level in two types of AITC-treated soils. The fungal phyla Basidiomycota, Glomeromycota, Zygomycota, and Chytridiomycota were decreased in AITC-treatment soils when the plants were presented. Populations of the fungal pathogens in the genus Alternaria, Aspergillus sesamicola and Aspergillus westerdijkiae were decreased in the AITC-treated tomato rhizosphere. Three potential beneficial bacterial isolates were enriched from the genera Acinetobacter and Pseudomonas communities. These were confirmed to have antifungal and antibacterial properties in pot growth plants. Further bioassays confirmed their roles in the suppression of bacterial wilt pathogens. The data suggest that AITC was critical to the characteristic microorganism of the microbial community in bulk soil, but when tomato plants were present, the plant had a greater effect on soil characteristic microorganism than AITC. AITC not only diminished some pathogenic fungi, but also enriched beneficial biocontrol microbes and reduced disease of tomato by suppressing bacterial and fungal pathogens in the soil.