Bacillus velezensis HY19 and application thereof

Abstract

The invention discloses bacillus velezensis HY19 and application thereof. The strain Bacillus velezensis HY19 is preserved in the China General Microbiological Culture Collection Center (CGMCC), the preservation date is January 4, 2021, and the preservation number is CGMCC No.21590. The strain can generate various water-soluble and volatile antibacterial substances, can effectively antagonize various plant pathogenic fungi, is wide in antibacterial spectrum and strong in antibacterial effect, has a relatively good biological prevention and treatment effect on flue-cured tobacco brown spot, is harmless to the ecological environment, and is not easy to cause drug resistance of pathogens. The strain has the characteristics of high breeding speed, high environmental adaptability, simple nutritional requirements, wide disease-resistant spectrum and the like, and is a novel biocontrol microorganism which is safe, efficient and capable of preventing and treating fungal diseases of plants in a broad-spectrum manner. The biocontrol microbial agent of the invention is simple in preparation method, easy for industrial production, and has good development and application prospects.

Description

technical field

[0001] The invention belongs to the technical field of biological control, and in particular relates to a bacillus HY19 and an application thereof. Background technique

[0002] Tobacco red spot disease (Alternaria alternata) is a fungal disease that threatens tobacco leaves the most in tobacco production. It has the characteristics of short incubation period and rapid prevalence. It occurs in all tobacco-growing provinces (regions) in my country, and the damage is serious in Heilongjiang, Henan, Shandong, Guizhou, Anhui, Sichuan and other provinces. The rate of diseased plants in general fields is 20% to 60%, and the rate of severely diseased fields can reach more than 90%. . As a result, the yield and quality of tobacco leaves are reduced, which seriously restricts the development of flue-cured tobacco production and causes heavy economic losses.

[0003] At present, for the prevention and treatment of red spot disease, chemical agent control is still the ...

Examples

Embodiment 1

[0029] Example 1 Isolation, screening and identification of strain Bacillus velezensis HY19

[0030] Isolation method: HY19 was isolated from the rhizosphere soil of healthy flue-cured tobacco plants in long-term rotation in Yuxi City, Yunnan Province in 2019. Isolation of microorganisms in soil by the dilution-and-spread plate method. Weigh 1.0 g of soil and place it in a 250 mL Erlenmeyer flask filled with 100 mL of sterile water, shake it in a shaker at 28 °C and 150 rpm for 1 h to prepare a soil suspension. Then, the soil suspension was diluted to 10 -2 、10 -3 、10 -4 、10 -5 、10 -6 and 10 -7different concentration gradients. Pipette 0.1mL of the soil suspension with the above dilution factor and spread it evenly on the NA plate. Repeat each dilution gradient 5 times. After the operation is completed, incubate the plate at 28°C for 2 days. , size to pick out different bacteria.

[0031] Screening method: Use the confrontation culture method to screen antagonistic ba...

Embodiment 2

[0041] The application of embodiment 2 bacterial strains Bacillus HY19

[0042] Preparation of fermentation broth: pick HY19 cells on the solid medium with an inoculation needle, inoculate in 1000mL sterilized NB medium, and culture on a shaking table for 24 hours (rotational speed: 150rpm, temperature: 28±1°C) to prepare Out of 10 6～9 cfu / mL of seed solution. Then, pour NB medium into a 100L fermenter, steam sterilize, add 1000mL seed liquid after sterilization, and cultivate for 120 hours (stirring rate: 150rpm, temperature: 28±1°C, ventilation: 0.1L / min) , prepare HY19 fermented liquid, set aside.

[0043] 1. Antagonistic effect of HY19 fermentation broth on pathogenic fungi.

[0044] The pathogenic fungi Colletotrichum gloeosporioides, Mycosphaerlla melonis, Alteraria alternata, Sclerotinia sclerotiorum, and Rhizoctonia solani were respectively inoculated in the center of the sterile PDA medium. ), wheat root rot (Bipolaris sorokiniana), pepper phytophthora (Phytophtho...

technical field

[0001] The invention belongs to the technical field of biological control, and in particular relates to a bacillus HY19 and an application thereof. Background technique

[0002] Tobacco red spot disease (Alternaria alternata) is a fungal disease that threatens tobacco leaves the most in tobacco production. It has the characteristics of short incubation period and rapid prevalence. It occurs in all tobacco-growing provinces (regions) in my country, and the damage is serious in Heilongjiang, Henan, Shandong, Guizhou, Anhui, Sichuan and other provinces. The rate of diseased plants in general fields is 20% to 60%, and the rate of severely diseased fields can reach more than 90%. . As a result, the yield and quality of tobacco leaves are reduced, which seriously restricts the development of flue-cured tobacco production and causes heavy economic losses.

[0003] At present, for the prevention and treatment of red spot disease, chemical agent control is still the ...

Examples

Embodiment 1

[0029] Example 1 Isolation, screening and identification of strain Bacillus velezensis HY19

[0030] Isolation method: HY19 was isolated from the rhizosphere soil of healthy flue-cured tobacco plants in long-term rotation in Yuxi City, Yunnan Province in 2019. Isolation of microorganisms in soil by the dilution-and-spread plate method. Weigh 1.0 g of soil and place it in a 250 mL Erlenmeyer flask filled with 100 mL of sterile water, shake it in a shaker at 28 °C and 150 rpm for 1 h to prepare a soil suspension. Then, the soil suspension was diluted to 10 -2 、10 -3 、10 -4 、10 -5 、10 -6 and 10 -7different concentration gradients. Pipette 0.1mL of the soil suspension with the above dilution factor and spread it evenly on the NA plate. Repeat each dilution gradient 5 times. After the operation is completed, incubate the plate at 28°C for 2 days. , size to pick out different bacteria.

[0031] Screening method: Use the confrontation culture method to screen antagonistic ba...

Embodiment 2

[0041] The application of embodiment 2 bacterial strains Bacillus HY19

[0042] Preparation of fermentation broth: pick HY19 cells on the solid medium with an inoculation needle, inoculate in 1000mL sterilized NB medium, and culture on a shaking table for 24 hours (rotational speed: 150rpm, temperature: 28±1°C) to prepare Out of 10 6～9 cfu / mL of seed solution. Then, pour NB medium into a 100L fermenter, steam sterilize, add 1000mL seed liquid after sterilization, and cultivate for 120 hours (stirring rate: 150rpm, temperature: 28±1°C, ventilation: 0.1L / min) , prepare HY19 fermented liquid, set aside.

[0043] 1. Antagonistic effect of HY19 fermentation broth on pathogenic fungi.

[0044] The pathogenic fungi Colletotrichum gloeosporioides, Mycosphaerlla melonis, Alteraria alternata, Sclerotinia sclerotiorum, and Rhizoctonia solani were respectively inoculated in the center of the sterile PDA medium. ), wheat root rot (Bipolaris sorokiniana), pepper phytophthora (Phytophtho...

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