CN-122012331-A - Guangdong slow rhizobium APHNZY-24-3 with functions of promoting growth and inhibiting aspergillus flavus and application thereof

Abstract

The invention discloses Guangdong slow rooting tumor bacteria (Bradyrhizobium guangdongense) APHNZY-24-3 with high-efficiency growth and nodulation promotion and aspergillus flavus inhibition functions and application thereof, and the number of the strain is CCTCC M2026225. The invention realizes the integration of the characteristic antibacterial volatile matter of benzothiazole production and the high-efficiency symbiotic nitrogen fixation on a single strain in the Guangdong slow rooting tumor for the first time. The benzothiazole produced by the bacterium can accurately down regulate the expression of toxin synthesis key genes and spore development core genes in the aspergillus flavus. The double targets of growth promotion, nitrogen fixation and source bacteriostasis can be synchronously realized in peanut rhizosphere-pod micro-domain through one-time inoculation, and particularly, a biological fumigation protective layer is constructed in soil in the critical period of pod development aiming at the biological characteristics of peanut 'underground results', so as to continuously block aspergillus flavus infection and toxigenesis.

Inventors

• ZHANG QI
• LI PEIWU
• ZHOU YANG

Assignees

• 中国农业科学院油料作物研究所

Dates

Publication Date

20260512

Application Date

20260212

Claims (6)

1. 1. The Guangdong slow-growing rhizobia APHNZY-24-3 with the functions of promoting growth and inhibiting aspergillus flavus is characterized by being classified and named Bradyrhizobium guangdongense, having a preservation number of CCTCC M2026225, a preservation date of 2026 and 23 months, and being preserved in China center for type culture collection, wherein the preservation unit address is in eight-path 299-number Wuhan universities in Wuhan district of Hubei province.
2. 2. A microbial agent or formulation comprising at least one of the cantonese slow rooting tumor bacteria APHNZY-24-3, its fermentation product or its culture according to claim 1, wherein the fermentation product comprises a fermentation broth, a sterile supernatant or an active substance extracted from the fermentation broth or the sterile supernatant, and the culture comprises a solid culture, a liquid culture or a dried formulation thereof.
3. 3. Use of the microbial agent or formulation of the cantonese slow rooting tumor cells APHNZY-24-3 according to claim 1 or claim 2 to promote peanut growth and nodulation and fix nitrogen.
4. 4. Use of a microbial agent or formulation according to claim 1, to inhibit aspergillus flavus growth, spore production and aflatoxin synthesis, of the cantonese slow rooting tumor bacteria APHNZY-24-3 or of claim 2.
5. 5. The use according to claim 4, wherein said inhibition function is achieved in particular by volatile organic compounds released by said cantonese slow rhizobia APHNZY-24-3.
6. 6. A method for inhibiting Aspergillus flavus, which is characterized by comprising the step of applying the Guangdong slow rooting tumor bacterium APHNZY-24-3 or the microbial agent or preparation of claim 2 to peanut planting environments or peanut plants.

Description

Guangdong slow rhizobium APHNZY-24-3 with functions of promoting growth and inhibiting aspergillus flavus and application thereof Technical Field The invention belongs to the technical field of agricultural microorganisms, and particularly relates to Guangdong slow rooting tumor bacteria (Bradyrhizobium guangdongense) APHNZY-24-3 with high-efficiency growth promotion and nitrogen fixation and strong aspergillus flavus inhibition functions and application thereof in green and safe production of peanuts. Technical Field Peanut as an important oil and commercial crop, its sustainable production faces two major core challenges, continuous yield increase and aflatoxin pollution control. The current industry mainly relies on two independent technical paths: The growth promoting and yield increasing technology mainly depends on the application of universal plant rhizosphere growth promoting bacteria (PGPR) inoculants, such as Bacillus spp, pseudomonas spp and the like. These bacterial agents provide nonspecific growth promotion by dissolving phosphorus, dissolving potassium or secreting hormones. However, the most efficient stimulation mechanism for leguminous crops such as peanuts is the formation of nodules with specific symbiotic nitrogen-fixing microorganisms (rhizobia). The general PGPR is unable to replace or efficiently activate this specific symbiotic system, and the yield-increasing potential has a fundamental bottleneck. The aflatoxin prevention and control technology mainly comprises 1) agricultural management measures (such as rotation) with passive and unstable effects, 2) physical and chemical methods (such as chemical fumigation and adsorbents) with high cost and residual and regulatory risks, and 3) biological prevention and control methods mainly applying antagonistic bacteria such as non-toxic aspergillus flavus and bacillus, and inhibiting pathogenic bacteria by competing or secreting antibacterial substances. Systematic defects and technical blanks exist in the prior art: (1) The function is single, the synergetic defect is that the existing growth promoting microbial inoculum (comprising the traditional rhizobium inoculant) generally lacks direct and efficient inhibition capability to aspergillus flavus, whereas the existing biological microbial inoculum lacks direct promotion effect to the symbiotic nitrogen fixation process of the leguminous crop cores. The microbial agents are applied in fields respectively, so that competition among microbial species is easy to cause, and the effects are unstable and even offset. (2) The technical path is split, and the source control problem is not solved, namely the aspergillus flavus infection starts from the field soil. The unique habit of peanut 'flowering on the ground and fruiting underground' causes the pods in the key development stage to be buried in the soil deeply, so that the traditional chemical prevention and control means face physical barriers in the fruiting stage, namely the seed coating effect is difficult to last, the foliar application cannot act on the underground pods, and the soil chemical treatment damages microecology and is easy to induce drug resistance. The prior art has the defects that the effective control means for the field pollution sources are seriously insufficient due to multiple post-treatment. (3) The core biological functions are not integrated, and particularly, the prior art fails to integrate the most efficient yield increasing mechanism (symbiotic nitrogen fixation) and the most critical toxin source prevention and control (rhizosphere bacteriostasis) of leguminous crops into the same biological carrier. To date, no public report or commercialized product relates to Guangdong slow rooting tumor bacteria which have high-efficiency symbiotic nitrogen fixation capability and can directly and effectively inhibit aspergillus flavus through generating characteristic volatile matters such as benzothiazole and the like. This is a technical gap to be filled in the field. Therefore, there is a need in the art for an integrated biological solution capable of synchronously achieving promotion of peanut symbiotic nitrogen fixation and source aspergillus flavus inhibition from the same ecological niche (rhizosphere), through the same microbial carrier and within the same growth cycle. The development of the multifunctional rhizobia has great significance for breaking through the technical bottlenecks of green, high-yield and safe production of peanuts. The present invention aims to provide this innovative solution. Disclosure of Invention In order to solve the defects in the prior art, the invention provides Guangdong slow-growing rhizobia APHNZY-24-3 with functions of promoting growth and inhibiting aspergillus flavus and application thereof. In order to solve the technical problems, the invention provides the following technical scheme: the first purpose of the invention is to provide a Guangdong slow-growing rhizobia APHN