KR20180118266A - Microbial pesticides against thrips - Google Patents

Abstract

The present invention relates to a microbial pesticide against thrips which comprises a beauveria bassian ERL 836 strain (KCCM11506P) or a spore thereof. The pesticide of the present invention exhibits a strong control activity equivalent to a conventional chemical pesticide against thrips, is eco-friendly, is easy to handle and manufacture and has excellent commercial utility.

Description

{Microbial pesticides against thrips}

The present invention relates to a microbial insecticide for controlling insect worms.

Thrips (Thrips spp.) Is an insect belonging to Thrips spp. It is an insect pest which causes all kinds of crops such as horticulture and flowers to bloom during the year and cause enormous damage. In particular flower thrips (Frankliniella occidentalis) and cucumber thrips (Thrips palm Karny ) is a foreign insect pest that has recently spread nationwide, causing serious damage to various crops, and it is particularly required to control the virus because it mediates viruses such as tomato spotting virus (TSWV). On the other hand, thrips are proliferative and resistance to chemical insecticides is faster than other pests. In addition, the insecticide is considered to be a relatively insect pest, because the insect repellent is caused by a mixture of various orders such as eggs, larvae, pupa, and adults after a generation has passed since about one month after intrusion into the facility.

About 220 kinds of chemical insecticides have been utilized to control thrips, such as pyridoxine and pinetoram. However, thrips are resistant to most of these chemical insecticides and are also resistant to recent research and development of chemical insecticides such as spinosad, acetamiprid, and deconfuran. (Methionine, cloppyrifos, diazino, etc.), synthetic pyrethroid insecticides (acrinatrine, ben petrolein, citric acid, etc.), insecticides (Spinosad), a methine insecticide (abamectin, milamectin, etc.), and the like, which are typical examples of the insect pests It has been reported as a resistant chemical insecticide.

Recently, the use of chemical insecticides has been gradually restricted due to the increasing interest in the adverse effects such as the emergence of resistant insect pests and the environmental pollution due to the continuous use and abuse of chemical insecticides. As a result, Control methods are being actively studied. For example, it is a method of controlling by using natural enemies such as Orius sp. And predatory mites, or by using insect pathogenic fungi that infects pests. More than 750 insect pathogenic fungi have been identified to date, including Beauveria bassiana , Metarhizium anisopliae , Nomuraea rileyi ) have been developed as microbial insecticides and have been used in various pest control.

In connection with the bovaria bacillus strains, Korean Patent Laid-Open Publication No. 10-2016-0000537 discloses an activity of controlling the bacterium Bacillus sp. FG274 and its parasitic larvae, and Korean Patent Laid-Open No. 10-2016-0139521 The control activity against the bovrieria bacillus SD15 strain and its spotted mite or peach lupus aphid, Korean Patent Laid-open Publication No. 10-2016-0084968 discloses a control activity against the bovaria bacillus JEF007 strain and its antibiotic backbone, Open No. 10-2011-0011239 discloses a strain of Bovia bacillus MaW1 and an active herbicidal or hairy tobacco control agent. Korean Patent Laid-Open Publication No. 10-2011-0094749 discloses an antiviral activity against a bovaria bacillus strain MsW1, , And Korean Patent Laid-Open Publication No. 10-2015-0113255 discloses an activity of controlling bacterium such as Bovaria bacillus and ERL 836 and water pests such as spermatozoa and rice weevil. However, there is still a need for new highly active microbial insecticides that are able to control spermatozoa as strongly as chemical pesticides and are environmentally friendly and easy to handle and use.

Korean Patent Publication No. 10-2016-0000537 Korean Patent Publication No. 10-2016-0139521 Korean Patent Publication No. 10-2016-0084968 Korean Patent Laid-Open No. 10-2011-0011239 Korean Patent Publication No. 10-2011-0094749 Korean Patent Publication No. 10-2015-0113255

The inventors of the present invention discovered that a bacteriocin ERL 386 strain exhibited a potent antimicrobial activity equivalent to that of a chemical insecticide against spermatozoa during the search for an environmentally friendly and powerful microbe insecticide for controlling insects.

Accordingly, it is an object of the present invention to provide an environment-friendly microbial insecticide which is easy to handle and use while exhibiting excellent control activity equivalent to that of conventional chemical insecticides against Thrips worms.

In order to achieve the above object,

The present invention provides a microbial insecticide for controlling insects such as bovaria bacillus or ERL 836 having an insect pathogenicity or a spore thereof.

In addition, the present invention provides a method for controlling insect bugs by applying the microbial insecticide of the present invention to a plant or soil to be protected from pests, their habitats, and pests.

The microbial pesticide containing the bovaria bacillus ERL 836 strain or the spore of the present invention exhibits a strong leveling activity against the insect pests of the same level as the conventional chemical insecticides, . It is also eco-friendly, easy to handle and manufacture, and has excellent commercial utility.

Fig. 1 shows a granular preparation of the microbial pesticide of the present invention.
FIG. 2 are photographs of colonies of the boveriac basiana ERL-836 strain of the present invention formed in soil after treating the soil with the microbial insecticide of the present invention.
FIG. 3 is a photograph showing that the insect pupa in the soil is actively contacting the colonies of the bovaria bacillus or ERL-836 strain of the present invention.
Figure 4 compares the sperm worm density in the treatment group treated with the microbial pesticide of the present invention, the control group treated with the chemical insecticide chlorothianidine, and the control group treated with no pesticide (a: after 20 days , b: after 40 days).
FIG. 5 shows a comparison of the density of spermatozoa in the treatment group treated with the microbial pesticide of the present invention, the comparison group treated with the spinnerot which is a chemical insecticide, and the control group not treated with any pesticide.
FIG. 6 shows a comparison of the density of spermatozoa in the treated group treated with the microbial insecticide of the present invention, the comparative group treated with the known strain of bovaria barbiana or GHA, and the control group treated with no pesticide.

The beauveria of the present invention bassiana ERL 836 (KCCM11506P) was isolated by the present inventor, and isolates of bovaria bacillus, which exhibit excellent insecticidal effect against water insects such as spermatozoa, brownflies, white beetles, and rice weevils, were isolated through bioassay Then, the isolated strain was morphologically identified, and the genomic DNA sequence was analyzed. The strain was identified as a bacteriobacteria strain having about 98% homology with the known bovaria bacillus strain GHA, and was identified as ERL 836 And deposited with the Korean Society of Microbiological Research (KCCM11506P) on January 22, 2014.

The bovaria bacillus ERL 836 strain of the present invention is disclosed in detail in Korean Patent Laid-open No. 10-2015-0113255, the entire contents of which are incorporated herein by reference. The bovaria bacillus strain ERL 836 of the present invention can be obtained from the above-mentioned conservation organs.

The B. bovisiana ERL836 strain forms a white community and exhibits very good sporulation ability and spore storage stability. For example, it exhibits excellent spore forming ability of about 4 to 6 times as much as that of the known bobbia bacillus or GHA strain, and exhibits spore storage stability of 2 to 3 times.

The bovaria bacillus strain ERL836 of the present invention can be applied to a host insect, such as chitinase, protease, lipase and / or esterase, It breaks through the cuticle layer of thrips and propagates in the body, producing toxic substances to block the immune function of the pests and to kill the host insects.

In the present invention, it was confirmed that the bovaria bacillus strain ERL836 has remarkably excellent insecticidal activity against the thrips, and thus it is possible to obtain the insecticidal activity against the thrips, such as flower yellow thrips, cucumber thrips, Frankliniella intonsa or Thrips tabaci Lindeman ). ≪ / RTI >

As previously mentioned, it is known that the "bobeliac basiana ERL836 strain" of the present invention effectively destroys water pests such as lizards. Thrips worms are a pest that occurs in flowering flowers or fruit trees, and has peculiar characteristics compared to water pests such as spermatozoa. Therefore, it is remarkable for a person skilled in the art that the bovaria bacillus and ERL836 strain of the present invention exhibits an insecticidal effect on a thrips worm, and it is not easily deduced from the insecticidal effect against existing water pests.

In the present invention, it was confirmed that the bovaria bacillus strain ERL836 had a strong controlling effect against the worms. Exhibited equivalent or better insecticidal effects (see Examples 4 and 5) than chemical insecticides such as chlorothianine or spinetoram, which are known to exhibit potent insecticidal activity against gibbits. In addition, it exhibited a remarkably excellent control effect as compared with the known bacterium, Bovia bacillus or GHA, which reported insecticidal activity against thrips (see Example 6)

The spore of the bovaria bacillus ERL 836 strain of the present invention can be produced by culturing the bovaria bacillus strain ERL836 in a solid culture medium.

The microbial pesticide of the present invention may be provided as a granular preparation, a liquid preparation or a compost.

Specifically, the granular formulation refers to a solid granular form, comprising the steps of: culturing the bovaria bacillus or ERL 836 strain in a solid culture medium; And harvesting the culture.

The solid culture medium may comprise any one selected from the group consisting of millet, white rice, wheat bran, millet, millet, and combinations thereof. The solid culture medium may be mixed with an organic acid, and the solid culture medium thus mixed with the organic acid may be immersed in water at 80 to 100 DEG C for 0.5 to 1.5 hours to absorb water. In the present invention, an organic acid such as citric acid is added to the mixture and then the water is absorbed in the water bath for 0.5 to 1.5 hours while maintaining the temperature at 80 to 100 DEG C, and the temperature is maintained at 110 to 130 DEG C for 10 to 40 minutes The solid culture medium was prepared by sterilization.

The organic acid is not particularly limited as long as it can be used as a carbon source. More specifically, any one selected from citric acid, propionic acid, butyric acid, lactic acid, succinic acid, clonic acid, valeric acid, caproic acid and combinations thereof can be used, and citric acid can be preferably used. The mixing of the organic acid and the solid culture medium can be carried out by adding and mixing an organic acid to the solid culture medium.

The culturing vessel for the strain may be a culture vessel commonly used in the technical field to which the present invention pertains, and is not limited thereto. For example, an oxygen supply filter capable of supplying oxygen smoothly to a polyvinyl bag can be attached and used for culturing.

Bovaria barbiana strain ERL 836 is inoculated into the prepared solid medium, then cultured at 20 to 30 ° C for 6 to 8 days, preferably at 25 ° C for 7 days. The inoculum to be used for the solid culture medium can be obtained by subculturing the bovaria barbiana strain ERL836, and the cultivation of the ERL836 strain can be carried out according to a conventional subculture method. The medium required for the subculture is not limited to that kind. As an example of the subculture medium, a liquid medium containing PDB (Potato Dextrose Broth) medium, rice bran or wheat bran can be used, but the type is not limited thereto. The harvested solid medium cultures are usually produced in granular form (see Figure 1).

The liquid formulation refers to a liquid form, comprising the steps of: culturing the bovis larva or ERL 836 strain in a solid culture medium; And enclosing the culture in a filter bag; And filtering the bag into water to elute the bovaria bacillus ERL 836 strain or spores thereof. The filter bag is a bag made of a water-permeable filter material. The filter bag may be a synthetic fiber of polyester, nylon, polyethylene, polypropylene and vinylon, a semi-synthetic fiber such as rayon, a woven or nonwoven fabric consisting of natural fibers of mulberry or mulberry tree alone or a composite fiber, Wood pulp, mixed paper made of polypropylene fiber, and paper.

Since the granular preparation undergoes a simpler production process than the liquid preparation, it can be advantageous in terms of shortening the period and reducing the cost.

On the other hand, it is known that the commercially available bovaria bacillus and GHA strains are used for insect worms, but they are known to have tolerance to pests in the soil. On the other hand, as will be described later, the granular preparation of the present invention showed excellent control effect on the pupa of the insect worm when applied to the soil. Therefore, the microbial insecticide of the present invention is applied to soil (including landfill, soil admixture, paddy field treatment, paddy field treatment, etc.) in the form of granular form, in addition to foliar treatment, which is a general treatment method of Biberia basiana strain, Can effectively kill the pupa. In addition, the applied strain of the present invention rapidly forms colonies in the soil, and thus can exhibit an insecticidal effect continuously, so that the application of repetitive insecticides can be minimized.

The microbial pesticide of the present invention may further comprise additives that are acceptable in the art.

The present invention also provides a method for controlling insect bugs, comprising applying the microbial insecticides to a plant or soil to be protected from pests, their habitats, and pests.

Examples of suitable crops are all crops with flowers such as horticulture and flowers, such as crops such as tomatoes, peppers, branches, potatoes and crops, watermelons, melons, cucumbers, peppers and other vegetable crops, lilies, carnations, chrysanthemums, And so forth.

The microbial pesticide of the present invention can be applied directly to the insects (adults, eggs, larvae, etc.) present in the ground and effectively controlling them, as well as being applied to the soil underground to control the insect pests (pupa) , It is possible to control thrips worms collectively. In particular, the insecticidal microorganism (fungus) of the present invention is treated in a soil (high humidity condition, nutrient existence) not in the ground part, smoothly propagated in the soil, and then settled in the ecosystem for a long time, have.

It is preferable that the microbial insecticide containing the bovisia barbiana ERL 836 strain or spores thereof of the present invention is applied in an amount of 10 ⁴ to 10 ⁸ spores / soil g in the case of soil treatment. When sprayed with a liquid formulation, a range of 10 ⁴ to 10 ⁸ spores / ml is preferred. When it is used in the above-mentioned range, usually sufficient control effect can be exhibited.

Hereinafter, preferred embodiments of the present invention will be described in order to facilitate understanding of the present invention. However, the following examples are provided only for the purpose of easier understanding of the present invention, and the present invention is not limited by the examples.

Example  1. Preparation of the microbial pesticide of the present invention (granule preparation)

A suspension (concentration: 1 × 10 ⁷ conidia / ml) was obtained by liquid culture of the boveriac basiana ERL 836 strain (KCCM11506P) (source: Korean Microorganism Conservation Center, Korean Society of Microbiology) at room temperature for 3 days in PDB medium. On the other hand, 200 g of Italian millet was placed in a polyvinyl bag for culture, 0.16 ml of 50% citric acid was further added, and the mixture was heat-treated at 90 ° C for 1 hour in a water bath So that the water was sufficiently absorbed in the tank to prepare a solid culture medium. At this time, the polyvinyl bag was sterilized at 121 ° C for 15 minutes using a paper cup and sterilized gauze to smoothly supply oxygen to the inlet. After cooling at room temperature, the prepared solid culture medium was inoculated with 1 ml of a suspension of bovaria barbiana strain ERL 836 (1 × 10 ⁷ conidia / ml), cultured at 25 ° C. for 7 days, and dried at room temperature for 1 day To obtain microbial pesticides of the present invention in the form of granules (see Fig. 1).

Example  2. Preparation of microbial pesticides of the present invention (liquid formulations)

10 g of the granules prepared in Example 1 were placed in a filter bag and sealed. Then, the mixture was placed in 10 L of water, followed by shaking, and the strain and spores were released into water to prepare a liquid preparation.

Example  3. Determination of Soil Fixability and Microbial Contact with Microbial Pesticides of the Present Invention After Soil Treatment

2 g of the microbial pesticide granule of the present invention obtained in Example 1 was treated with soil, and after 7 days, the soil fixation of the bovaria bacillus and ERL 836 strain was observed and the contact with the larvae and larvae of the insect larvae was observed. And FIG. 3, respectively. The bacterium Bovia bacillus 836 started to proliferate from 3 days after the soil treatment and was colonized smoothly in the soil (see FIG. 2). Also, the pupae present in the soil contacted the strain colonies of the present invention very actively (Fig. 3).

Example  4. Identification of the effect of the microbial pesticide of the present invention on the control of the thrips

The effect of controlling insecticides was studied in tomato crops. Tomato crops were used at 20-25 cm height. In order to inhibit the flowering of yellow and yellow worms in the processing zone, tomato crops were grown in plastic cages (30 × 30 × 60 cm < ³ >).

2 g of the microbial pesticide granules of the present invention prepared in Example 1 were treated in a pot planted with tomato crops. As a comparative group, 0.02g (i.e., 3kg / 10a) of chlorothianidine, which is a chemical pesticide known to exhibit a strong insecticidal effect on Thrips worms, was treated, and no insecticide was applied to the control port.

As can be seen in Table 1 and FIG. 4, the microbial pesticide of the present invention exhibited a potent control effect (85-95%) at a level similar to that of clotheidinine, against Thrips worms.

Example  5. The microbial pesticide of the present invention has a Insecticidal effect  Confirm

The insecticidal effect test of the microbial insecticide of the present invention against the insect worm was performed in a large greenhouse condition.

After the cucumber was fixed in a large greenhouse, the insecticidal granules (concentration: 10 ⁷ conidia / g) of the present invention prepared in Example 1 were treated at the throughput of 3 kg / 10 a to the cucumber plant. As a comparative group, spinetoram WDG (concentration: 5% by weight, water dispersible granular form), which is a pesticide known to exhibit a strong insecticidal effect on spermatozoa, was subjected to initial foliage treatment at a throughput of 0.5 g / L. On the other hand, no pesticides were treated in the control group. After 5 days of treatment with insecticides, the amount of spermatozoa in the treated group, the control group and the control group was visually examined and the change in population density was analyzed until the final 6 weeks, and it is shown in Fig. In Figure 5, the unit of average density is the number of flies per plant.

In addition, control efficacy was calculated by the following formula to evaluate the pesticide efficacy.

Comparative efficacy = (D _control -D _treatment ) / D _control x 100

In the above equation, the D _control means the average density of the worms in the control group in which the insecticide is not treated at all, and the D _treatment means the average density of the worms in the treatment group treated with the insecticide.

As can be seen from Table 2 and FIG. 5, the microbial pesticide of the present invention exhibited a better controlling effect than the spinetoram WDG against Thrips worms.

Example  6. ERL836 and With GHA  Comparison of the effect of controlling insect worms (indoor test)

The control effect of the bovaria bacillus and ERL836 strain of the present invention against the thrips was confirmed in comparison with the existing bovaria bacillus and GHA strains. The comparative experiments were conducted on chrysanthemum crops. Chrysanthemum crops were grown at a height of about 20 cm. In order to inhibit the flowering of yellow and yellow worms in the treatment zone, the chrysanthemum crops were grown in plastic cages (30 × 30 × 60 cm ³ ).

2 g of the microbial pesticide granules of the present invention prepared in Example 1 were treated in a pot in which the chrysanthemum plant was planted. In addition, as a comparative group, the GHA strain was solid-cultured in the same manner as in Example 1 for the ERL836, and 2 g of the obtained granules were treated for chrysanthemum. One week after the insecticide treatment, five insects of the flower yellow insects were sprouted in each of the two microbial treatment groups and the control group (no treatment), and then the density of the insect worms was measured for 6 weeks at intervals of two weeks. 6.

As shown in Table 3 and FIG. 6, the microbial insecticide of the present invention exhibited an insecticidal effect remarkably superior to that of the conventional bovaria bacillus or GHA strain against Thrips worms.

Claims (7)

Microbial insecticides for controlling insect worms containing the boveriac basiana ERL 836 strain (KCCM11506P) or spores thereof as active ingredients. The microbial insecticide according to claim 1, wherein the thrips are flower yellow thrips, cucumber thrips, Taiwan thrips or thrips. The microbial insecticide according to claim 1 or 2, which is in the form of a solid granule, for controlling insect worms. The microorganism insecticidal composition according to claim 3, which is a solid granular form obtained by culturing the boveriac basiana strain ERL 836 (KCCM 11506P) in a solid culture medium selected from millet, white rice, wheat bran, millet, . 4. The microbial insecticide according to claim 3, which is applied to soil. A method for controlling insect bugs, comprising applying the microbial insecticide according to any one of claims 1 to 5 to a plant or soil to be protected from pests, their habitats and pests. 7. The method according to claim 6, comprising applying to soil.

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