CN-122012335-A - Sinorhizobium meliloti ASZJHZ-4 with functions of promoting growth and inhibiting aspergillus flavus and application thereof

Abstract

The invention discloses sinorhizobium meliloti (Sinorhizobium meliloti) ASZJHZ-4 with high-efficiency growth promoting and aspergillus flavus inhibiting functions and application thereof, and the preservation number is CCTCC M2026230. The invention realizes the integration of the characteristic antibacterial volatile matter of producing 2-methyl butyric acid and the high-efficiency symbiotic nitrogen fixation on a single strain in sinorhizobium meliloti for the first time. The 2-methylbutyric acid volatile matters released by the strain can accurately down regulate the expression of toxin synthesis key genes and spore development core genes in the aspergillus flavus, thereby realizing efficient bacteriostasis on a molecular level. Through one-time inoculation, the double targets of promoting growth and fixing nitrogen and inhibiting bacteria from the source can be synchronously realized in the peanut rhizosphere ecological niche. Particularly, aiming at the biological characteristics of peanut 'flowering on the ground and fruiting on the ground', a durable biological fumigation protective layer is formed in the soil microenvironment in the critical period of pod development.

Inventors

• LI PEIWU
• ZHANG QI
• 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 sinorhizobium meliloti ‌ ASZJHZ-4 with the functions of promoting growth and inhibiting aspergillus flavus is characterized by being classified and named Sinorhizobium meliloti, having a preservation number of CCTCC M2026230, a preservation date of 2026 and 23 months, and being preserved in China center for type culture collection, wherein the preservation unit address is eight-path 299-number Wuhan university in Wuchang district of Wuhan, hubei province.
2. 2. A microbial agent or formulation comprising at least one of sinorhizobium meliloti ‌ ASZJHZ-4, a fermentation product thereof or a culture thereof 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 wherein the culture comprises a solid culture, a liquid culture or a dry formulation thereof.
3. 3. Use of the microbial inoculant or formulation of sinorhizobium meliloti ‌ ASZJHZ-4 as claimed in claim 1 or claim 2 for promoting peanut growth and nodulation and nitrogen fixation.
4. 4. Use of the microbial agent or formulation of sinorhizobium meliloti ‌ ASZJHZ-4 as claimed in claim 1 or of the microbial agent or formulation of claim 2 for inhibiting aspergillus flavus growth, spore production and aflatoxin synthesis.
5. 5. The use according to claim 4, wherein the inhibition function is achieved in particular by volatile organic compounds released by sinorhizobium meliloti ‌ ASZJHZ-4.
6. 6. A method for inhibiting Aspergillus flavus is characterized by comprising the step of applying the Sinorhizobium meliloti ‌ ASZJHZ-4 of claim 1 or the microbial agent or preparation of claim 2 to peanut planting environments or peanut plants.

Description

Sinorhizobium meliloti ASZJHZ-4 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 sinorhizobium meliloti (Sinorhizobium meliloti) ASZJHZ-4 with high-efficiency growth promotion and nitrogen fixation and strong aspergillus flavus inhibition functions and application thereof in green and safe production of peanuts. Background 1. Importance and core challenges of the peanut industry The peanuts are used as global important oil and cash crops, and the safe production of the peanuts has strategic significance for guaranteeing the supply of grain and oil, increasing the income of farmers and maintaining the stable trade. However, the sustainable production faces two major challenges of yield improvement and aflatoxin contamination prevention and control. Aflatoxins (AFs) are strong carcinogens generated by aspergillus flavus (Aspergillus flavus) infection, which not only seriously harm food safety and consumer health, but also often trigger international trade technical barriers, and become a key bottleneck for restricting the high-quality development of the peanut industry. 2. Core mechanism for increasing yield of leguminous crops and action of sinorhizobium For leguminous crops such as peanuts, the most efficient yield increasing way is to establish a specific symbiotic relation with rhizobia to form root nodules, and convert nitrogen in the atmosphere into nitrogen sources available for plants. Sinorhizobium meliloti (Sinorhizobium meliloti) is a known rhizobium group capable of efficiently symbiotic with various leguminous plants, and has important application potential in promoting plant nodulation and nitrogen fixation. However, the traditional rhizobia agents have single functions, mainly focus on nitrogen fixation and growth promotion, and generally lack direct antagonism capability on soil-borne pathogenic fungi such as aspergillus flavus. 3. Limitations of the existing aflatoxin prevention and control technology At present, aflatoxin prevention and control mainly depends on agricultural management measures, a physicochemical method and biological control mainly comprising Bacillus spp and Trichoderma spp. These methods or effects are passively unstable or costly and present a risk of chemical residues. Particularly, the unique growth habit of the peanuts such as flowering on the ground and fruiting on the ground makes the traditional chemical or biological prevention and control means based on the overground parts difficult to effectively act on fruits in soil in the critical period of pod development and infection, and forms obvious physical prevention and control barriers. 4. Systematic drawbacks of prior art paths The current "yield increase" and "gas defense" in peanut production are split into two parallel but independent systems on a technical path, and this structural split results in the following deep systematic defects: (1) Loss of function singleization and biological synergy The design core of the existing growth promoting microbial inoculum (comprising the traditional rhizobium inoculant) mainly surrounds growth promoting physiological mechanisms such as nitrogen fixation, phosphorus dissolution, hormone production and the like, has single functional localization, and generally lacks direct and high-efficiency inhibition capability on specific soil-borne pathogenic fungi such as aspergillus flavus and the like. On the contrary, the breeding and application of the existing biological control bacterial agent take antagonism pathogenic bacteria as a core target, the metabolic pathway and action mechanism of the biological control bacterial agent are not directly related to the promotion of plant growth (especially the symbiotic nitrogen fixation process specific to leguminous crops), and the colonization and the co-production establishment of rhizobia can be interfered even due to nutrition competition, space occupation or secretion of inhibitory metabolites. The two kinds of microorganisms with single functions are simultaneously introduced into the complex ecological system of the rhizosphere, so that functional complementation and synergistic interaction are difficult to realize, and the field effect is unstable and unpredictable and even weakened mutually due to competition or antagonism among microorganism seeds, so that the technical dilemma of 1+1<2 is formed. (2) Complicated operation and obviously increased comprehensive cost In actual production, farmers need to purchase, store, formulate and apply two different types of microbial preparations respectively. The double-product double-flow application mode not only directly increases the material cost of seed treatment or field operation, but also greatly improves the labor input, equipment use and time management cost. The complex operation flow reduces the operability and