CN111602663A

CN111602663A - Suspension type thread-killing seed coating agent

Info

Publication number: CN111602663A
Application number: CN201910136745.3A
Authority: CN
Inventors: 简恒; 毛雯; 刘倩
Original assignee: China Agricultural University
Current assignee: China Agricultural University
Priority date: 2019-02-25
Filing date: 2019-02-25
Publication date: 2020-09-01

Abstract

The invention provides a suspension type thread-killing seed coating agent. The invention provides a suspension type thread-killing seed coating agent, which consists of the following components: lufuda: 417-1668g a.i/100kg seed; film-forming agent: 5 percent; dyeing agent: 2 to 3 percent. The application of the suspension type thread-killing seed coating agent in the prevention and treatment of the tomato root-knot nematode disease also belongs to the protection scope of the invention. The invention provides a novel thread-killing seed coating agent, which is screened to obtain a Lufuda dose which does not cause phytotoxicity to tomatoes and has a control effect on meloidogyne incognita, and the dosage is greatly reduced compared with the conventional pesticide application mode.

Description

Suspension type thread-killing seed coating agent

Technical Field

The invention relates to the field of root-knot nematode control, in particular to a novel seed coating agent with a control effect on root-knot nematodes.

Background

Plant parasitic nematodes are an important group of plant pathogens that occur and are harmful in many countries and regions of the world. The root-knot nematode is a plant parasitic nematode which is the most harmful in agriculture, has wide distribution area and various hosts, and can parasitize more than 2000 different economic crops such as oil crops, vegetables, tea, fruit trees, tobacco, traditional Chinese medicinal materials and the like. Statistically, the annual loss rate of the root-knot nematode to major crops in the world is about 5%, and the economic loss exceeds 500 billion dollars. With the continuous adjustment of agricultural industrial structure, the continuous enlargement of vegetable production area and the continuous improvement of multiple cropping index in China, good conditions are provided for the large-scale occurrence of root-knot nematode diseases. At present, root-knot nematode diseases are reported in greenhouses in south and north areas of China and are serious. According to the estimation, the annual loss of vegetables in China caused by the root-knot nematode harm exceeds hundreds of millions of yuan. In vegetable crops mainly comprising tomatoes, plant nematode diseases are increased year by year, and the yield of diseased land is reduced by more than 20 percent, and seriously reaches more than 75 percent, even no harvest occurs. Meanwhile, the root-knot nematode can enable fungi and bacteria to easily infect plants, and further induce plant diseases. At present, the prevention and control of plant parasitic nematodes are mainly chemical prevention and control, but chemical nematicides are few in variety, are high in toxicity and residue, and seriously pollute and damage the environment.

At present, a novel nematicide which is provided by Bayer company and contains 41.7 percent of fluopyram suspending agent as an effective component appears on the market. Has the characteristics of high safety, environmental protection, low dosage and long lasting period. The luofu expression shows unique and obviously different mobility from other nematicides in soil, so that the luofu expression can be slowly and uniformly distributed in rhizosphere soil, and the luofu expression can effectively protect plant root systems from being infected by nematodes for a long time in the rhizosphere range due to the moving distribution characteristic of the luofu expression in the soil. The traditional application method of Lufuda is to irrigate roots by adding water according to the recommended dose after the tomatoes are planted, and the liquid medicine consumption of each plant is 400 ml. The formulation is a suspension formulation, is thick and thick, but the dosage is easy to generate inaccurate phenomenon, the combination is rich in the characteristics of the formulation and is more suitable for being prepared into seed coating agent for use, in addition, the initial stage of emergence is an important period for preventing and treating nematode infection, the existing application mode can not meet the requirement of nematode prevention and treatment at the initial stage of emergence, and the seed coating agent can more effectively protect the seedling growth of plants.

Disclosure of Invention

The invention aims to provide a suspension type thread-killing seed coating agent with low toxicity and good prevention and treatment effect.

The invention provides a suspension type thread-killing seed coating agent, which consists of the following components:

lufuda: 417-1668g a.i/100kg seed; (g a.i/100kg seed, which means 417-;

film-forming agent: 5 percent;

dyeing agent: 2 to 3 percent.

Wherein the percentages are relative to the mass of the seed, such as 0.05kg of film former and 0.03-0.03kg of colorant per 1kg of seed.

The film forming agent can be specifically an AF400 film forming agent;

the coloring agent may specifically be allura red 85.

Specifically, the suspension type thread-killing seed coating agent consists of the following components:

lufuda: 1668g a.i/100kg seed;

film-forming agent: 5 percent;

dyeing agent: 2 to 3 percent.

Or, the suspension type thread-killing seed coating agent consists of the following components:

lufuda: 834g a.i/100kg seed;

film-forming agent: 5 percent;

dyeing agent: 2 to 3 percent.

lufuda: 417g a.i/100kg seed;

film-forming agent: 5 percent;

dyeing agent: 2 to 3 percent.

The application of the suspension type nematocide in preventing and controlling tomato root knot nematode also belongs to the protection scope of the invention.

The invention provides a novel thread-killing seed coating agent, which is characterized in that a Lufuda dose which does not cause phytotoxicity to tomatoes and has certain control effect on meloidogyne incognita is screened, the dosage is greatly reduced compared with a conventional pesticide application mode, labor force is saved, and the seedling growth of the tomatoes can be more effectively protected.

Drawings

FIG. 1 is a graph showing the effect of coating tomato seeds with the coating agent of the present invention in example 1 of the present invention. Wherein, 1 is uncoated tomato seeds, and 2 is coated tomato seeds.

FIG. 2-1 shows the emergence of seedlings after 10 days of sowing; fig. 2-2 shows the emergence of seedlings for 15 days after sowing, wherein a, blank control b is diluted 1 time c, d, e, f, g, h, e.

FIG. 3 shows the specific growth state of the seeds treated differently in example 2 of the present invention.

FIG. 4 shows the results of the different treatments of tomato in example 3 of the present invention for 5, 7 and 10 days to inoculate nematodes.

FIG. 5 shows the disease of tomato roots treated differently for 60 days in a pot experiment, wherein 1 is a clear water control; 2, processing fosthiazate; 3 is 40 times; 4 is 20 times; 5 is 10 times.

Detailed Description

The present invention will be described below with reference to specific examples, but the present invention is not limited thereto.

The experimental methods used in the following examples are all conventional methods unless otherwise specified; reagents, biomaterials, etc. used in the following examples are commercially available unless otherwise specified.

Example 1 preliminary screening of coating concentration of Lufuda tomato seeds

The concentration gradient dilution of 41.7% of a suspending agent purchased from Bayer is carried out from 1 time to 100 times, and the suspending agent, an AF400 film-forming agent (purchased from Beijing Greentechnologies), a coloring agent allura red 85 (purchased from Zhejiang Jigagde pigment technologies Co., Ltd.) and tomato seeds are evenly mixed with Qiangfeng ginkgo nuts (purchased from Tianjinxing technologies Co., Ltd.) according to the proportion of 200mL/g seeds, 0.05g/g seeds and 0.02-0.03g/g seeds, and then the mixture is dried. The coating effect is shown in figure 1.

And sowing the dried coated seeds with various concentrations in a seedling raising plug tray filled with sterilized soil. Observing the growth conditions of the seeds treated with different concentrations at the initial stage of germination, wherein in the figure 2, the seeds are diluted by 1 time, 2 times, 4 times, 6 times, 8 times, 10 times and 20 times and then applied, and the phytotoxicity conditions are applied at the initial stage of emergence;

as can be seen from fig. 2: dilution times less than 10 times have obvious phytotoxicity at the early stage of emergence.

The concentration of the screened medicament is as large as possible to meet the effect of preventing and controlling the nematodes without causing phytotoxicity, and finally, the concentration is diluted to 10 times, namely the coating concentration is 1668g a.i/100kg (the seed amount is small when the coating is tried, namely 1g of seeds are coated, 0.1g of Loufida raw medicament is diluted by 10 times by water, the diluted solution is diluted to 1mL, 400 microliters of Loufida medicament 0.04g (Fluopyram is multiplied by 41.7%: 0.01668g) is added to coat the seeds, when the seeds are converted into 100kg, the Fluopyram content is 1668g, and the growth condition of the seeds in the initial germination stage is not different from that of a control when the seeds are diluted by 10 times, 20 times and 40 times for convenience of distinguishing, the next step is adopted, and two kinds of coating concentrations with the higher dilution times, namely 20 times, 40 times, namely the coating concentration and 417g a.i/100kg are selected for research on the basis. Hereinafter, the seed coating agent is expressed in different concentrations by 10 times, 20 times, and 40 times.

Example 2 Effect of different coating concentrations on tomato seed Germination and tomato seedling growth

1. Effect of seed coating agent on tomato seed Germination

Sterile round filter paper is padded in a sterile culture dish with the diameter of 120mm, 100 coated seeds of different strains are uniformly placed after being wetted by sterile water, and the treatment is repeated for 3 times in each treatment of 3 dishes, and uncoated seeds are taken as a control. Culturing in an incubator at 28 deg.C and 85% humidity. And investigating the condition of primary germination in 24 hours, calculating the germination potential according to a formula in 3 days, and calculating the germination rate according to a formula in 5 days. The specific formula is as follows:

germination potential, GE ═ 3d seed germination number/total test seed number × 100%

The germination rate is that the germination number of seeds in GP-5 d/the total number of the co-test seeds is multiplied by 100 percent

TABLE 1 tomato seed germination vigor and germination rate treated with different seed coating agents

The results in table 1 show that the germination potential and germination rate of tomato seeds are slightly reduced with the increase of the concentration of the drug in the seed coating agent, but no significant difference is shown. (failure example, dilution concentration cannot be adjusted to 1-10 times)

2. Influence of seed coating agent on growth vigor of tomato seedlings

Sowing the seeds with different treatments in a seedling raising plug tray filled with sterilized soil, culturing in a greenhouse at 25 ℃, and investigating physiological indexes such as plant height, fresh weight of the overground part, fresh weight of the underground part and the like after 25 days. The specific growth state is shown in table 2 and fig. 3.

TABLE 2 physiological indices of tomato seedlings treated with different seed coatings

The result shows that the three physiological indexes of the height of the tomato seedlings, the fresh weight of the overground part and the fresh weight of the underground part are slightly reduced with the increase of the concentration of the medicament in the seed coating, but no significant difference is shown.

Example 3 prevention and treatment Effect of seed coating agent on tomato root knot nematode disease

1. Sowing evaluation prevention effect in direct sowing mode

Seeds with different treatments are sown in seedling raising plug trays filled with sterilized soil, the seeds are cultivated in a greenhouse at 25 ℃, egg masses of Meloidogyne incognita (Meloidogyne incognita) in the greenhouse are collected during the cultivation period (the Meloidogyne incognita used in the experiment is separated, purified and cultivated from greenhouse disease soil in a laboratory, but the Meloidogyne incognita is seriously damaged and can be collected in a diseased greenhouse), and hatched two-instar larva suspension is collected and the concentration of the nematode is adjusted to be 500 heads/mL for later use.

The method for starting to inoculate the second-instar larvae after tomato seeds are sowed for about 10 days comprises the following steps: 3-5cm deep small holes are inserted near the tomato seedling root, 4 small holes are used for each plant, and the prepared suspension of the second-instar larvae is injected into the small holes, wherein the inoculation amount is 200J 2 plants. And covering the holes with soil after inoculation. Watering at proper time to keep the soil moist, so as to be beneficial to nematode infection. The number of nematodes infecting tomato root tissue at different treatments was investigated at 5d, 7d and 10d after inoculation. The specific investigation method is as follows:

after inoculation for 5d, 7d and 10d, 15 tomato seedlings are taken for each treatment, the nematodes in root tissues are stained, the number of the nematodes is counted under a dissecting mirror, and the population reduction rate is calculated. The specific number of infections is shown in FIG. 4.

(1) The root tissue staining method (sodium hypochlorite acid fuchsin staining method) was as follows:

a. the washed roots were placed in a 150mL beaker, and 30mL of a 5% NaClO solution from distillers was added thereto, followed by stirring with a glass rod for 4 min.

b. The roots were removed with forceps, rinsed under tap water for 40s, then placed in a clean glass, and soaked in 50mL of distilled water for 15 min.

c. The water in the cup was decanted, 30mL of distilled water and 1mL of acid fuchsin solution were added again, and the cup was gently shaken to homogenize the solution.

d. The cup was placed in a microwave oven and heated for about 1min20s and then taken out and immediately placed on ice for cooling.

e. After the solution was cooled, the stained root tissue was removed with forceps and the surface water was blotted with paper.

f. After the cup is cleaned, 20mL of glycerol is added, 2 drops of 5mL/L HCl are absorbed by a rubber head dropper and added and mixed evenly. Heating in microwave oven for 2min to boil, taking out, and placing root therein for fading.

(2) Method for calculating oral cavity decline rate (%) - (control individual population-treated individual population)/control individual population × 100

TABLE 3 reduction of population by different seed coating treatments

The results show that the higher the concentration of the agent, the higher the reduction rate, and that the reduction rate decreases with time under the same seed coating treatment (table 3).

2. Transplanting mode seeding evaluation prevention effect

Sowing the seeds with different treatments in a seedling raising plug tray filled with sterilized soil, and culturing in a greenhouse at 25 ℃. Fully mixing the nutrient soil, vermiculite and chicken manure according to the volume ratio of 3:1:1, carrying out dry heat sterilization at 180 ℃ for 3 hours, and filling into a plastic basin with the specification of 20cm multiplied by 20cm after sterilization and cooling. After 4 true leaves grow out of the tomato seedlings, transplanting the tomato seedlings to plastic pots with soil, one for each pot, and treating for 30 pots, wherein the number of treatments is 5, and the treatments comprise three concentrations of seed coating agents, clear water control and fosthiazate pesticide control.

Inoculating meloidogyne incognita to the tomato seedlings after 3-5 days of field planting. The inoculation method comprises the following steps: collecting eggs of Meloidogyne incognita (Meloidogyne incognita) in a greenhouse (the Meloidogyne incognita used in the experiment is separated, purified and cultured in greenhouse disease soil in the laboratory, but the Meloidogyne incognita is seriously harmful and can be collected in the greenhouse with disease), collecting the hatched suspension of the second instar larvae, and adjusting the concentration of the nematodes to be 500 heads/mL for later use. 3-5cm deep small holes are inserted near the tomato seedling root, 4 small holes are used for each plant, and the prepared second-instar larva suspension is uniformly injected into the small holes, wherein each hole is 1m, namely, each plant is connected with 2000 heads J2. After inoculation, the small holes are covered with soil, and a proper amount of water is poured into the small holes to keep the soil moist, so that nematode infection is facilitated.

And after 60 days of nematode inoculation, randomly taking out 8 tomato seedlings for each treatment, investigating the root knot count through the grading standard of the root knot grade, and calculating the control effect according to a formula. The specific root onset is shown in FIG. 5.

TABLE 4 potted plant test root knot series with different treatments and control effect

As can be seen from the pot experiment results: when the tomatoes are planted for 60 days, the treatment control effects of the fosthiazate and the seed coating agent are respectively 58.7%, 21.8%, 28.3% and 31% in an amount which is 40 times, 20 times and 10 times. I.e., fosthiazate, the control was the highest and the seed coating treatment decreased with decreasing agent concentration (table 4).

In practical application, in order to achieve the thread killing effect of diluting 10 times to prepare the seed coating agent, 4kg of seeds are required to be applied for 100kg of seeds, and since 1668g of a.i/100kg seed, namely 1668 g/41.7% ═ 4kg, the dosage of each seed is estimated to be about 0.0001g of the seed coating agent, and the dosage of each tomato seedling in the traditional application mode is 0.02-0.03g, the dosage of the agent is greatly reduced.

Claims

1. A suspension type thread-killing seed coating agent comprises the following components:

lufuda: 417-1668g a.i/100kg seed;

film-forming agent: 5 percent;

dyeing agent: 2 to 3 percent.

2. The suspension type nematicidal seed coat agent according to claim 1, wherein: the film forming agent is an AF400 film forming agent;

the coloring agent is allura red 85.

3. The suspension type nematicidal seed coat agent according to claim 1, wherein: the suspension type thread-killing seed coating agent consists of the following components:

lufuda: 1668g a.i/100kg seed;

film-forming agent: 5 percent;

dyeing agent: 2 to 3 percent.

4. The suspension type nematicidal seed coat agent according to claim 1, wherein: the suspension type thread-killing seed coating agent consists of the following components:

lufuda: 834g a.i/100kg seed;

film-forming agent: 5 percent;

dyeing agent: 2 to 3 percent.

5. The suspension type nematicidal seed coat agent according to claim 1, wherein: the suspension type thread-killing seed coating agent consists of the following components:

lufuda: 417g a.i/100kg seed;

film-forming agent: 5 percent;

dyeing agent: 2 to 3 percent.

6. The use of the suspended nematicidal seed coating according to any one of claims 1 to 5 for the control of tomato root knot nematode disease.