A promising product: Abscisic acid-producing bacterial agents for restricting cadmium enrichment in field vegetable crops

Soil heavy metal contamination and its enrichment in the edible parts of crops have gained global concern. In this study, a compound bacterial agent possessing the ability to produce the plant hormone, abscisic acid (ABA), was applied to contaminated farmland in Hunan province. Its application reduced the concentration of Cd in radish, cabbage, mustard, and lettuce by 15–144%. Accordingly, the Cd contents in these vegetables were found to be below the maximum limits set by GB 2762–2017. Meanwhile, bacteria agents also led to a significant increase in crops yield by 45–82%. Furthermore, the nutritional indices, including soluble sugar and soluble protein increased by 18–66%, as well as the antioxidant indices, including total phenolic, ascorbate content, and DPPH capacity, enhanced by 12–76%, 10–49% and 50–140%, respectively. In conclusion, the use of ABA-producing bacteria is anticipated to be a novel approach for the safe use of soil with moderate and low pollution.