Composition containing bacillus subtilis and epsilon-polylysine for preventing and treating fusarium diseases of crops and application of composition

Abstract

The invention relates to a composition containing bacillus subtilis and epsilon-polylysine for preventing and treating fusarium diseases of crops and application of the composition, and belongs to the technical field of agricultural biology. The bacillus subtilis is named as bacillus subtilis JDBS-89, and the preservation number of the bacillus subtilis is CCTCC (China Center for Type Culture Collection) NO. M 20231482. The epsilon-polylysine is produced through streptomyces fermentation, and the molecular weight of the epsilon-polylysine is 3500-5000D. Compared with the prior art, the pesticide composition disclosed by the invention has the beneficial effects that (1) products and technologies for preventing and treating fusarium diseases of crops by using the composition of bacillus subtilis and epsilon-polylysine are not found on the market; and (2) the two effective components have a synergistic effect, so that the control effect on fusarium diseases of crops is enhanced, and the propagation of the diseases is effectively controlled.

Description

Technical Field

[0001] The invention relates to a composition containing Bacillus subtilis and epsilon-polylysine for preventing and treating Fusarium diseases of crops and application thereof, belonging to the field of agricultural biotechnology. Background Art

[0002] Fusarium spp. is a type of fungus distributed worldwide, commonly found in soil and plant and animal organisms. It is an important type of pathogen. After infecting plants, it can cause root rot, stem rot, stem base rot, ear rot, flower rot, fruit rot and other diseases. It can infect the vascular system of plants, destroy the conductive tissues of plants, and make the organs of the infected parts unable to obtain sufficient water and nutrients, causing plant wilt, withering of leaves and leaf buds, and even death, seriously affecting the yield and quality of crops.

[0003] Fusarium oxysporum has a wide range of hosts and can invade the vascular bundle from the root tip, fibrous root or lateral root and main root wound of crops. It uses plant tissues in the vascular bundle as nutrition, colonizes and multiplies in the vascular bundle, and produces a large number of hyphae and conidia that block the vascular bundle vessels, causing crops to wilt. It can cause wilt diseases in more than 100 crops such as Solanaceae, Leguminosae, Cucurbitaceae, Banana, Flowers, Fruit Trees, etc. Fusarium graminearum can cause a wide range of diseases in Gramineae crops such as wheat, such as wheat scab, which seriously affects the quality and yield of wheat. At the same time, the fungal toxins it produces also seriously threaten the health of humans and animals.

[0004] In current agricultural production, the prevention and control of wilt caused by Fusarium wilt mainly relies on chemical fungicides such as methyl thiophanate, carbendazim, pyrimethanil, and tebuconazole. The long-term use of these conventional fungicides has led to an increase in the number of uses and drug concentrations year by year, and pathogens have also developed a certain resistance to conventional fungicides. Compared with chemical fungicides, the use of microbial preparations and natural products has better environmental compatibility and safety. With people's attention to food safety and environmental protection, the development of low-toxic, high-efficiency, and low-residue biological preparations has become an important direction for pesticide development in recent years.

[0005] Bacillus subtilis is gaining more and more attention as a biocontrol agent. It has a fast growth rate, strong environmental adaptability, and good stress resistance, which is conducive to mass cultivation and colonization and propagation in field environments. The antimicrobial peptides secreted by Bacillus subtilis can inhibit the production and germination of pathogenic spores, dissolve cell walls, leak protoplasm, and deform mycelium. The secreted secondary metabolites such as macrolides, phenols, and polyenes can inhibit the growth of pathogens by changing the permeability of cell membranes, or inhibit the activity of pathogens by inhibiting prokaryotic protein synthesis.

[0006] ε-Polylysine is the product of the combination of the carbonyl group at the α-position of lysine and the amino group at the ε-position. It is composed of 25-30 lysine residues. It has a synergistic effect when used in combination with hydrochloric acid, citric acid, malic acid, glycine and higher fatty glycerides. It is a polypeptide with antibacterial effect and has a certain inhibitory effect on the growth of yeast, mold and bacteria. Summary of the invention

[0007] The purpose of the present invention is to provide a composition containing Bacillus subtilis and ε-polylysine, and to provide an application of the composition in preventing and controlling Fusarium diseases of crops.

[0008] To achieve the above object, the present invention adopts the following technical scheme: a composition containing Bacillus subtilis and ε-polylysine is used for preventing and controlling Fusarium diseases of crops, and its active ingredients are Bacillus subtilis and ε-polylysine.

[0009] The Bacillus subtilis of the present invention is obtained by screening a large number of Bacillus subtilis biocontrol strains in a plate confrontation experiment of simultaneously antagonizing ε-polylysine and Fusarium oxysporum. The Bacillus subtilis is named Bacillus subtilis JDBS-89, and the preservation number is CCTCC NO.M 20231482.

[0010] The ε-polylysine of the present invention is produced by fermentation of Streptomyces, and has a molecular weight of 3500-5000 D. Plant living body experiments show that the ε-polylysine has a certain effect on preventing and controlling Fusarium diseases of crops.

[0011] The structural formula of the ε-polylysine of the present invention is as follows:

[0012]

[0013] Furthermore, the weight ratio of the active ingredient Bacillus subtilis JDBS-89 to ε-polylysine is 1:30-50:1.

[0014] Furthermore, the weight ratio of the active ingredient Bacillus subtilis JDBS-89 to ε-polylysine is 1:5-20:1.

[0015] Furthermore, the composition of the present invention may also contain other general pesticide adjuvants, such as a wetting agent, a thickener, a dispersant, a disintegrant, an antifreeze agent, a defoaming agent, an emulsifier, a solvent, a filler, a pH regulator, or water, or a combination thereof.

[0016] Furthermore, the composition of the present invention is in the form of an aqueous solution, a water-dispersible granule, an aqueous emulsion, a microemulsion, a suspension, a seed coating agent, a wettable powder, a granule, or the like.

[0017] Furthermore, the composition of the present invention is applied by root irrigation, spraying, broadcasting, furrow application or hole application.

[0018] Compared with the prior art, the composition of the present invention has the following beneficial effects:

[0019] (1) There are no products or technologies on the market that use a combination of Bacillus subtilis and ε-polylysine for preventing and controlling Fusarium diseases in crops.

[0020] (2) The two active ingredients of the present invention have a synergistic effect, which enhances the control effect on crop Fusarium diseases and effectively controls the spread of diseases. DETAILED DESCRIPTION

[0021] The present invention is further described below in conjunction with preferred embodiments, but the protection scope of the present invention is not limited thereby.

[0022] The composition of the invention uses Bacillus subtilis JDBS-89 and ε-polylysine as effective active ingredients, which are combined in a certain ratio and have an obvious synergistic effect on the prevention and treatment of crop fusarium diseases.

[0023] The fermentation medium of Bacillus subtilis JDBS-89 in the composition of the present invention is formulated as follows: 10-40 g / L bean cake powder, 10-30 g / L corn flour, 5-15 g / L glucose, 5-10 g / L corn peptone, 1-5 g / L yeast extract, 1-5 g / L potassium dihydrogen phosphate, 1-3 g / L ammonium sulfate, 0.2-1 g / L magnesium sulfate, 0.01-0.2 g / L ferrous sulfate, and the initial pH of the fermentation is 7.0-7.2. The liquid volume of a 100L fermentation tank is 75L, the culture conditions are 37°C, the speed of the stirring paddle is 180 rpm, the tank pressure is 0.11 MPa, the ventilation volume is 1-1.5 VVM, and the tank is released when the spore rate is ≥95%, thereby obtaining a Bacillus subtilis fermentation liquid of 18 billion cfu / mL.

[0024] The compatibility ratio and concentration of the composition of the present invention are shown in Table 1:

[0025] Table 1 Composition ratio and concentration Example description

[0026]

[0027] The above examples were tested in a greenhouse using the following protocol:

[0028] (1) The isolated and purified Fusarium oxysporum was inoculated onto a PDA plate (potato 200 g / L, glucose 20 g / L, agar 20 g / L, natural pH) and cultured at 25°C for 5-7 days. After the mycelium was fully grown, 10-20 mL of sterile water was added, and the spores were gently scraped off with an inoculation loop. The mycelium was filtered through 4 layers of gauze, and the spore suspension was adjusted to 2 × 10 6 cfu / mL.

[0029] (2) In the greenhouse, transplant one 10-day-old cucumber seedling into each pot.

[0030] (3) 10 days after the cucumber seedlings were planted, the soil around the roots was gently removed and wounds were made on the roots of the plants with sterile scissors. 300 mL of spore suspension was then irrigated into the roots and the soil was covered after the spore suspension had fully contacted the roots.

[0031] (4) Five days after inoculation with Fusarium oxysporum, each plant of Examples 1 to 9, Control 1, and Control 2 was irrigated with 500 mL of water according to the specified dilution multiple. A commercially available 5 billion cfu / g Trichoderma harzianum powder diluted 500 times, a 15% ethoxypropane emulsifiable concentrate diluted 500 times, and a 20% carbendazim suspension diluted 1500 times were also used as control agent treatments, and the root irrigation dosage for each treatment was 500 mL. At the same time, an equal amount of clean water was used as a negative control for root irrigation.

[0032] (5) After 30 days, each plant was irrigated with the same agent again.

[0033] (6) 10 pots per treatment.

[0034] (7) 90 days after the first root irrigation, investigate the disease status of plants with different treatments, calculate the disease index and calculate the prevention effect.

[0035] Classification standards and prevention efficiency calculation method:

[0036] Grade 1: asymptomatic;

[0037] Level 2: 0-25% of branches and leaves are withered or yellowed;

[0038] Level 3: 26-50% of branches and leaves are withered or yellowed;

[0039] Level 4: 51-75% of branches and leaves are withered or yellowed;

[0040] Level 5: More than 75% of the branches and leaves are withered or yellowed, or the whole plant is dead.

[0041] Disease index = ∑ (disease level × number of plants at the corresponding level) / (total number of plants surveyed × highest disease level) × 100

[0042] Control effect (%) = ∑ (disease index of control area - disease index of treated area) / disease index of control area × 100

[0043] The protective efficacy test data of the embodiments and control agents are shown in Table 2:

[0044] Table 2: Test data of the protective effect of the embodiment and the control agent

[0045]

[0046] It can be seen from the above control effect data that after Bacillus subtilis JDBS-89 and ε-polylysine are combined, there is a certain synergistic effect on the prevention and treatment of wilt caused by Fusarium. The control effects of Example 2 and Example 8 both exceed the control effect of the positive control agent carbendazim. The best control effect is Example 8, which has an increase of 30.0% and 56.0% compared with Control 1 and Control 2, respectively. Bacillus subtilis JDBS-89 and ε-polylysine have a significant synergistic effect.

Claims

1. A composition for preventing and controlling Fusarium diseases of crops, the active ingredient of which is Bacillus subtilis subtilis JDBS-89) and ε-polylysine.

2. The composition for preventing and controlling Fusarium diseases of crops according to claim 1, characterized in that: The weight ratio of Bacillus subtilis JDBS-89 and ε-polylysine in the effective components is 1:30-50:

1.

3. The composition for preventing and controlling Fusarium diseases of crops according to claims 1-2, characterized in that: The weight ratio of Bacillus subtilis JDBS-89 to ε-polylysine in the active ingredient is preferably 1:5-20:

1.

4. The composition for preventing and controlling Fusarium diseases of crops according to any one of claims 1 to 3, characterized in that: The composition may further comprise other general pesticide adjuvants, such as a wetting agent, a thickener, a dispersant, a disintegrant, an antifreeze agent, a defoaming agent, an emulsifier, a solvent, a filler, a pH regulator, or water, or a combination thereof.

5. The composition for preventing and controlling Fusarium diseases of crops according to any one of claim 4, characterized in that: The total content of active ingredients Bacillus subtilis JDBS-89 and ε-polylysine in the composition is 5-80% of the composition.

6. The composition for preventing and controlling Fusarium diseases of crops according to any one of claim 5, characterized in that: The total content of the active ingredients Bacillus subtilis JDBS-89 and ε-polylysine in the composition is preferably 25-60% of the composition.

7. The composition for preventing and controlling Fusarium diseases of crops according to any one of claim 5, characterized in that: The dosage form of the composition is any one of aqueous solution, water dispersible granules, aqueous emulsion, microemulsion, suspension, seed coating agent, wettable powder, granules and the like.

8. The composition according to any one of claims 1 to 3, characterized in that: The application methods are root irrigation, spraying, broadcasting, furrow application or hole application.

9. The use of the composition according to any one of claims 1 to 3, characterized in that: Used to control crop diseases caused by Fusarium.

10. The use according to claim 9, characterized in that: The crop diseases caused by the Fusarium include wilt, root rot, stem rot, stem base rot, ear rot, blossom rot, fruit rot, wheat fusarium rust and other diseases.

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