CN115191444A

CN115191444A - Bactericidal composition containing rhodopseudomonas palustris and isoprothiolane

Info

Publication number: CN115191444A
Application number: CN202210972112.8A
Authority: CN
Inventors: 陈岳; 刘勇; 张德咏; 谭新球; 吴希阳; 李成刚; 张鑫
Original assignee: HUNAN PLANT PROTECTION INSTITUTE
Current assignee: HUNAN PLANT PROTECTION INSTITUTE
Priority date: 2022-08-15
Filing date: 2022-08-15
Publication date: 2022-10-18

Abstract

The invention provides a bactericidal composition containing rhodopseudomonas palustris and isoprothiolane, wherein the mass ratio of rhodopseudomonas palustris bacterial liquid to isoprothiolane is 1-50; the concentration of rhodopseudomonas palustris bacterial liquid is 1-9 multiplied by 10 ⁹ cfu/mL. The bactericidal composition can be used for preventing and treating rice blast, has a remarkable synergistic effect, can effectively reduce the using dosage of active ingredients, and can slow down the generation of drug resistance of diseases.

Description

Bactericidal composition containing rhodopseudomonas palustris and isoprothiolane

Technical Field

The invention belongs to the field of pesticide compositions, and particularly relates to a bactericidal composition containing rhodopseudomonas palustris and isoprothiolane and application thereof.

Background

China is a big agricultural country, and rice is an important grain source in China, so that the quality and the disease control of rice are always important matters concerned by people. The rice blast is one of the main diseases of rice, and the rice can be attacked in the whole growth period. The disease can occur in leaves, nodes, ear necks, grains and other parts, and is commonly seen in plague of leaves, neck plague of ears, stalk blast, etc. The rice blast is common in China, can cause withering of rice seedling leaves and short joints when the rice blast occurs seriously, forms white ears and blighted grains, and has great influence on the yield of rice when the rice blast occurs seriously. The prevention and control of the rice blast mainly adopts the measures of breeding disease-resistant varieties, preventing and controlling medicaments, strengthening cultivation management and the like. Most of the disease-resistant varieties are vertical resistant varieties based on the theory of gene-to-gene, the genetic variation of rice blast germs is very frequent, and the physiological race composition and structure of a single disease-resistant variety are easy to change after long-term large-area use, so that the disease resistance is lost.

The chemical control has the advantages of economy, effectiveness, convenience, quick effect and the like, so the chemical control is always an important component in a rice blast comprehensive treatment system. However, the pesticide resistance is enhanced and found out in time, so that the pesticide application is extremely unscientific and reasonable, the pesticide application dosage and times seriously exceed the standard, and the serious problems of environmental pollution, agricultural product quality safety and the like are caused. Therefore, how to reduce the pesticide dosage and comprehensively prevent and control rice blast in a green way is still an important problem in rice production in China at present.

The applicant finds that rhodopseudomonas palustris has excellent control effect on rice blast and false smut in earlier research. For example, CN201610333926 discloses the use of Rhodopseudomonas palustris fermentation broth for the prevention and control of rice blast, wherein the Rhodopseudomonas palustris fermentation broth is obtained by culturing Rhodopseudomonas palustris LY-6 (Rhodopseudomonas palustris LY-6). CN201610333888 discloses application of Rhodopseudomonas palustris biocontrol agent in preventing and controlling rice blast, which is characterized in that the Rhodopseudomonas palustris biocontrol agent is obtained by culturing Rhodopseudomonas palustris LY-6 (Rhodopseudomonas palustris LY-6). In addition, the applicant also researches that the rhodopseudomonas palustris has good control effect on various diseases such as potato scab, tomato chlorosis virus, potato late blight, bacterial streak and the like.

The isoprothiolane has special effect on rice blast, and after being absorbed by rice plants, the isoprothiolane can inhibit the invasion of pathogenic bacteria, particularly inhibit phosphatide N-methyltransferase, thereby inhibiting the growth of the pathogenic bacteria and playing roles in prevention and treatment. The pesticide is applied for 1 time respectively in the opening period and the heading period for preventing and treating rice blast, and can also be used for preventing and treating large leaf spot of corn, small leaf spot of corn, barley stripe disease and leaf streak disease. However, the long-term use of isoprothiolane results in serious resistance to diseases.

In the prior art, no report is provided about the application of the combination of rhodopseudomonas palustris and isoprothiolane in the prevention and control of rice blast.

Disclosure of Invention

In order to solve the problems in the prior art, the invention provides the following technical scheme:

a sterilization composition containing rhodopseudomonas palustris and isoprothiolane comprises 1-50 mass ratio of rhodopseudomonas palustris bacteria liquid to isoprothiolane; the concentration of rhodopseudomonas palustris bacterial liquid is 1-9 multiplied by 10 ⁹ cfu/mL. Preferably, the mass ratio of the rhodopseudomonas palustris bacterial liquid to the isoprothiolane is 1-50. The concentration of the preferable rhodopseudomonas palustris bacterial liquid is 2-5 x 10 ⁹ cfu/mL。

The bactericidal composition also comprises auxiliary material components acceptable for pesticides, and the prepared pesticide is any acceptable preparation. Such as suspending agents, wettable powders and the like

The bactericidal composition provided by the invention is used for preventing and treating rice blast.

Preferably, rhodopseudomonas palustris LY-6 (Rhodopseudomonas palustris LY-6) adopted in the application is preserved in China center for type culture Collection with the preservation number of CCTCC NO: m2014525, the preservation unit address is located at Wuhan university in China, the preservation date is 29 months 10 in 2014, and the strain is named as Rhodopseudomonas palustris LY-6 (Rhodopseudomonas palustris LY-6 is patented and has patent application number: 201410750073.2).

Reference is made to the preparation of Rhodopseudomonas palustris LY-6 (patent application No.: 201410750073.2):

(1) And (3) activation: culturing the preserved species of the rhodopseudomonas palustris strain according to a double-layer plate culture method until a red single colony appears;

(2) Seed culture: inoculating the red single colony cultured in the step (1) into a serum bottle, and culturing to a logarithmic phase by using a photosynthetic bacteria liquid culture medium under the conditions that the temperature is 30-32 ℃, the illumination condition is 2500 Lx-4000 Lx and the pH is 7.0 to obtain a bacterial liquid;

(3) Production and culture: inoculating the bacterial liquid obtained after the seed culture in the step (2) into a production bottle, and performing production culture by using a photosynthetic bacteria production culture medium, wherein the inoculum size of the bacterial liquid is 5 percent of the total volume of the photosynthetic bacteria strain production culture medium, and the bacterial liquid is cultured to a logarithmic phase under the conditions that the temperature is 30-32 ℃, the illumination condition is 2500 Lx-4000 Lx and the pH = 7.0;

concentration of rhodopseudomonas palustris bacterial liquid is 1-9 x 10 ⁹ cfu/mL。

By adopting the technical scheme, the invention has the following beneficial effects:

the rhodopseudomonas palustris and the isoprothiolane have obvious synergistic effect on rice blast germs after being compounded, can reduce the use dosage of active ingredients and slow down the generation of drug resistance of diseases.

Detailed Description

The present invention will be further explained with reference to specific embodiments.

Example 1: indoor toxicity determination of compound agent on rice blast

Test strains: pyricularia oryzae (Magnaporthe oryzae); and (4) collecting, separating and purifying in an experiment base.

Reagent to be tested:

rhodopseudomonas palustris bacterial liquid (a): concentration 5X 10 ⁹ cfu/mL；

Isoprothiolane (B), a raw drug, is commercially available.

The test method comprises the following steps:

inhibition by hypha growth rate method. On the basis of a pre-experiment, each test medicament is prepared into dilution with a series of concentrations under the aseptic condition. Adding the mixture into a melted PDA culture medium according to a certain proportion under an aseptic condition, mixing, pouring into a sterilized culture dish, and preparing a series of drug-containing culture medium flat plates with concentration gradients; the rice blast strain to be tested is firstly cultured on a PDA culture medium at 25 ℃ for 5-7 days, when bacterial colonies grow to the edge of a culture dish, a punch with the diameter of 5mm is used for punching bacterial cakes at the edge of the bacterial colonies, and then the bacterial cakes are moved to the center of a culture medium plate containing the medicine. Control was performed on non-dosed plate medium. 1 block per plate, 1 treatment per dose, 4 replicates per treatment.

According to the growth condition of the bacteria in a blank control culture dish, investigating the growth condition of hyphae of pathogenic bacteria, measuring the diameter of a bacterial colony by using a caliper, measuring each bacterial colony for 2 times by a cross method, representing the size of the bacterial colony by the average number of the bacterial colony, and calculating the bacteriostasis rate and the virulence index, wherein the calculation formula is as follows: inhibition = (control colony diameter-treatment colony diameter)/control colony diameter × 100%.

Calculating the virulence index and the cotoxicity coefficient (CTC) of the medicament according to the Sun Yunpei method.

Measured virulence index (ATI) = (standard agent EC 50/test agent EC 50) × 100;

theoretical virulence index (TTI) = a agent virulence index x percent of a in the mixture + B agent virulence index x percent of B in the mixture;

co-toxicity coefficient (CTC) = [ measured toxicity index (ATI)/theoretical toxicity index of the mixture (TTI) ] × 100;

when CTC is less than or equal to 80, the composition shows antagonism; when 80 < CTC < 120, the composition exhibits additive effects; when the CTC is more than or equal to 120, the composition shows synergistic effect.

And (3) testing results: the rhodopseudomonas palustris and the isoprothiolane are compounded to show different combined effects on rice blast germs of rice; when the proportion of rhodopseudomonas palustris to isoprothiolane is 1-50.

Table 1: indoor toxicity determination of compound agent on rice blast

Example 2 field control of the Compound Agents against Pyricularia oryzae

Test site: chunhua test base

And (3) testing crop diseases: blast of rice

The test method comprises the following steps: the drug treatment and blank control were set, each treatment was repeated 3 times, the cell area was 50m2, the cells were protected and randomly arranged in blocks. And in the opening period of the rice, spraying clean water with the same amount in a blank control area by adopting a manual sprayer to spray on the leaf surfaces and the spike parts of the rice. And no other bactericide is sprayed during the test period, and the field management is carried out according to the convention.

30 days after the pesticide is applied, the disease condition of the rice panicle plague is investigated by a parallel skip sampling method, 20 holes are investigated in each cell, and the disease index and the control effect are calculated (the disease index refers to GBT17980.19-2000, and the field efficacy test criterion-bactericide control rice leaf diseases).

And (3) testing results: compared with the single use, the prevention and treatment effect of the pesticide on rice blast can be obviously improved after the rhodopseudomonas palustris and the isoprothiolane are compounded.

Table 2: field control effect of compound agent on rice blast

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit the same.

Claims

1. A sterilization composition containing rhodopseudomonas palustris and isoprothiolane is characterized in that the mass ratio of rhodopseudomonas palustris bacteria liquid to isoprothiolane is 1-50; the concentration of rhodopseudomonas palustris bacterial liquid is 1-9 multiplied by 10 ⁹ cfu/mL。

2. The bactericidal composition according to claim 1, wherein the mass ratio of the rhodopseudomonas palustris bacterial liquid to the isoprothiolane is 1.

3. The bactericidal composition of claim 1 or 2, wherein the Rhodopseudomonas palustris is Rhodopseudomonas palustris LY-6 (Rhodopseudomonas palustris LY-6) deposited at the chinese type culture collection with a collection number of CCTCC NO: and M2014525.

4. The bactericidal composition of claim 1, wherein the concentration of the rhodopseudomonas palustris bacterial solution is 2 to 5 x 10 ⁹ cfu/mL。

5. The bactericidal composition of any one of claims 1-4, further comprising a pesticidally acceptable adjuvant ingredient.

6. The bactericidal composition of claim 5, wherein the bactericidal composition is formulated as a suspension concentrate or a wettable powder.

7. Use of the fungicidal composition according to claims 1 to 6 for the control of Pyricularia oryzae.