JPS6048901A - Controlling agent against plant viral blight - Google Patents

Abstract

PURPOSE:An agent, prepared by molding an active substance having a controlling activity against plant viral blights supported on gluten, etc. into a form insertible into a plant body, having improved penetrability into the plant body, and capable of exhibiting improved controlling effect regardless of infectious routes without phytotoxicity. CONSTITUTION:A controlling agent, prepared by adding an active substance, having a controlling activity against plant viral blights, e.g. a culture of a mold or a substance collected therefrom, to gluten or its mixture with another high polymer, e.g. alginic acid or starch, at a weight ratio of the gluten of 35wt% or more, preferably by kneading with an adequate amount of water, molding the resultant mixture into a form suitable for inserting into a plant body, preferably a rodlike material having at least one tip of acute angle, and drying the resultant molded material. EFFECT:The controlling agent is capable of releasing and penetrating even the active substance having a high molecular weight slowly into the plant body, exhibiting the prolonged controlling effect on plant viral blights without causing phytotoxicity even in using the above-mentioned active substance in a relatively large amount.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a plant virus disease control agent for protecting plants from plant virus diseases.

Research on the control of plant virus diseases has been carried out for a long time, and various anti-plant virus active ingredients have been reported, but none that are practically satisfactory have yet been provided. This is based on the fact that many anti-plant virus active ingredients cause phytotoxicity to plants or have poor permeability into plant bodies.

For example, Plastocygen S, which is known as an antibiotic that exhibits strong anti-plant virus activity at low concentrations, is highly effective in controlling plant virus diseases, but it also causes significant phytotoxicity to plants, so it can hardly be put to practical use. It is said that there is no such thing, and recently,
Active ingredients of cultures of microorganisms belonging to filamentous fungi or those collected from them, developed as anti-plant virus active ingredients that are unlikely to cause phytotoxicity to plants (Japanese Patent Application Laid-Open No. 52-3
No. 821) is a high-molecular substance with a molecular weight of about 10,000 to 10,000, so when it is sprayed on the leaves of a plant, it does not penetrate into the plant body, and even if it is tried to be absorbed through the roots, it is hardly absorbed. Therefore, even if the culture or the active ingredient collected from it can control viral diseases transmitted by contact through the so-called foliar treatment method, it has almost no control effect on viral diseases transmitted by insect vectors. .

Due to the above-mentioned circumstances, there has been a strong demand for the development of a plant virus disease control agent that exhibits a control effect on plant virus diseases regardless of the transmission route and does not cause phytotoxicity to plants.

The present invention has been made in view of the current situation as described above, and is a new form that has permeability into the plant body and is not harmful to plants. The purpose of the present invention is to provide a plant virus disease control agent.

The structural feature of the present invention is that gluten or a mixture of gluten and a high molecular weight substance supported by a substance having a control activity against plant virus diseases is inserted into the plant body. The reason is that it is molded into a molded product with a shape suitable for.

That is, as a result of studying the incorporation into plants of an anti-plant virus disease active ingredient made of a polymeric substance that does not have permeability into the plant body, the present invention provides a method for supporting the active ingredient in a water-permeable polymeric substance. When the molded product is inserted into a plant body, the active ingredient is gradually released and permeates into the plant body; This is based on the knowledge that gluten and mixtures of gluten and other polymeric substances are suitable as such water-permeable polymeric substances.

As described above, in the present invention, a plant virus disease controlling active substance is supported on gluten or a mixture of gluten and other polymeric substances, and when gluten is used as the mixture, gluten is at least 10% by weight or more, Preferably, a mixture of 35% by weight or more is used.

The polymer substances used here in combination with gluten are:
Natural polymer substances such as alginic acid and its derivatives, starch and its derivatives, dextrin, pectin, gelatin, agar, locust bean gum, acacia, xanthan gum, guar gum and its derivatives, or polyvinyl alcohol, polyacrylic acid, polymethacrylic acid, etc. Examples include synthetic polymeric substances. Note that one or more of these polymeric substances may be used in combination with gluten.

In the present invention, in order to support a substance having plant virus disease control activity on gluten or a mixture of gluten and the above-mentioned polymeric substance, the active substance is added to gluten or the above-mentioned mixture, and then an appropriate amount of water is added and mixed. Then, this mixture is molded into a shape suitable for insertion into a plant and dried to obtain the desired molded product. Also,
In this molding, a viscous polymeric substance soluble in an organic solvent such as pine resin may be used instead of water.

In the present invention, the plant virus disease controlling active substances used by being supported on gluten or a mixture of gluten and the above-mentioned polymeric substances include plasticidin S, famidin, naramycin, which are antibiotics having controlling activity against plant viruses, Formycin B, etc., as well as cultures of filamentous fungi belonging to the genus Aspergillus, which are said to have little phytotoxicity, or active ingredients for controlling plant virus diseases obtained therefrom (Japanese Patent Laid-Open Publication No. 1983-1982)
No. 3821), etc. may be exemplified. Note that it is also possible to support the above-mentioned antibiotic and a culture of filamentous fungi in combination.

The amount of these active substances supported in the molded product must be kept below the amount that does not cause phytotoxicity, since antibiotics such as plasticidin S have strong phytotoxicity to plants. Surprisingly, when supported on a molded product, the above-mentioned active substance gradually dissolves into the plant body, causing no phytotoxicity even when supported in an amount of about 1,100 pp or more, and providing a sustained effect against plant virus diseases. It begins to exhibit a pest control effect. Incidentally, when plasticidin S is sprayed with grass leaves, even with an IPPM solution, the leaf surface curls and growth is delayed, which causes phytotoxicity. In addition, in a culture of the above-mentioned filamentous fungi belonging to the genus Aspergillus, which is not harmful to plants, it is possible to carry about 0.1 to 25% by weight.

In the present invention, gluten carrying an active substance for controlling plant virus diseases or a mixture of gluten and other polymeric substances is molded into a molded article having a shape suitable for insertion into a plant body.

The "shape suitable for insertion into a plant body" as used herein may be any shape that can be inserted into any part of a plant body, and examples thereof include a rod shape, a thin plate shape, an ellipsoid shape, a spherical shape, etc. However, when used by inserting it into the stem of a plant, a rod-shaped body with at least one end having an acute angle is particularly preferable because it is easy to insert the rod-shaped body. In addition, when inserting a molded article into the shape described above into a plant body, insert the molded article into the plant body using an appropriate method, and tape the insertion point to prevent the inserted molded article from falling off. Wrap it around and fix it, or
Alternatively, it is preferable to use a suitable tool to hold the material.

As mentioned above, when a molded product in which gluten or a mixture of gluten and other polymeric substances is supported on a plant virus disease controlling active substance is inserted into a plant body, the active substance supports the gluten or other polymeric substance. As the above-mentioned mixture permeates into the plant body due to its vesicular permeability, it gradually elutes into the plant body, so as mentioned above, even in the case of active substances with strong phytotoxicity, it can continuously act on plant viruses without causing phytotoxicity. It becomes like this. Therefore, the pest control agent according to the present invention exhibits an excellent control effect not only against plant virus diseases transmitted by contact but also against plant virus diseases transmitted by insect vectors.

As mentioned above, the plant virus disease control agent according to the present invention,
Since it can be applied by being inserted into the plant body, even high molecular weight plant virus disease control active substances can be gradually released and permeated into the plant body, and exhibit a sustained plant virus disease control effect. In addition, it has the advantage of not causing any phytotoxicity even if the above-mentioned active substance, which has conventionally been difficult to put into practical use due to its phytotoxicity to plants, is used in relatively large amounts.

EXAMPLES The structure and effects of the present invention will be explained in more detail below with reference to Examples.

Example 1 25 parts by weight of a plant virus disease control active substance in powder form obtained by drying a culture of the NF-1244 strain belonging to the genus Aspergillus (Feikoken Bacteria No. 3100) was mixed with 40 parts by weight of gluten powder. and 35 parts by weight of rosin powder, and half the amount of water was added to this mixture and kneaded, and the mixture was formed into a rod shape with a diameter of about Inn and a length of about 2 m111, and one tip of the rod was made at an acute angle. It was formed into a shape. The molded product thus obtained was sterilized at 120°C for 3 minutes and then dried at 40°C to obtain a plant virus disease control agent comprising the molded product.

Next, one stick of the insecticide obtained as described above was inserted into the stem of a green bean (major awn) as a test plant, and the following day it was applied to some groups of green beans, and then to other groups of green beans. After 5 days, tobacco mosaic virus (common type) dissolved in 0.1M phosphate buffer (pif 7.0) was inoculated using the carborundum method. As a control, a group to which no insecticide was applied was prepared.

As a result of examining the number of lesions on the test plots of each of the above groups four days after the above inoculation, it was found that in the test plots of the group injected with the insect repellent, the number of local lesions that appeared on the leaves of green beans was less than 10% on average. However, lesions were seen all over the body in the test area of the control group.

Example 2 A pest control agent prepared in the same manner as described in Example 1 was
Two weeks after germination, the stems of cucumbers (Kinari Sandagi) are inoculated, and three days later each cucumber is infected with cotton aphids (3 heads/plant) to remove the aphids. Cucumber mosaic virus was inoculated using this as a vector. As a control, cucumber mosaic virus was also inoculated into a group of cucumbers that were not injected with the insecticide.

Two weeks after inoculation according to 1., we investigated the state of virus disease in the cucumber groups in each test plot.As a result, in the test plot injected with the insecticide, 10 cucumber plants developed systemic disease symptoms. In contrast, in the control test plot, disease was observed in 10 out of 10 plants. When the insecticide was removed from each cucumber after the investigation, it was found that the cucumbers retained almost their original shape.

Example 3 1 part by weight of a plant virus disease controlling active substance consisting of a dry powder of the culture of the NF-1244 strain used in Example 1 and 30.005 parts by weight of plasticidin were mixed with 45 parts by weight of gluten powder and pine resin powder. This mixture was thoroughly mixed with 40 parts by weight and 15 parts by weight of locust bean gum, and this mixture was molded in the same manner as described in Example 1, sterilized, and then dried to obtain a plant virus disease control agent consisting of a molded product. .

Next, this control agent was applied to the stem of a tomato (Fukuju No. 2) planted in a No. 3 pot after 3 weeks of germination, and 3 days later, tobacco mosaic virus was inoculated in the same manner as in Example 1. did. In addition, a group of tomatoes that were not inoculated with the insecticide and similarly inoculated with the above virus was used as a control.

Two weeks after the above inoculation, we investigated the disease onset status in each test plot, and found that only 5 out of 20 plants in the test plot injected with the insecticide showed systemic disease symptoms. In contrast, in the control group, the ratio was 17 out of 20.

Furthermore, two weeks later, the plots injected with the insecticide were re-inoculated with tobacco mosaic virus, and when examined two weeks later, only 2 out of 20 tomatoes developed systemic disease symptoms. .

Example 4 1 30.01 parts by weight of plasticidin and 99 parts by weight of gluten powder
．． 9 parts by weight were thoroughly mixed, and this mixture was molded in the same manner as described in Example 1, sterilized, and dried to obtain a plant virus disease control agent consisting of a molded product.

Next, this insecticide was applied to the stem of Toma 1- (Fukuju No. 2) planted in a No. 3 pot after 3 weeks of germination. This group was inoculated with tobacco mosaic virus after 3 days and the remaining groups after 6 days, respectively, following a procedure similar to that described in Example 1. A group of tomatoes that were not injected with the pesticide was used as a control group.

Two weeks after inoculation according to 1., we investigated the development of systemic disease symptoms in the test plots of each group, and found that 1.
Expression was observed at a rate of 1 out of 0 plants, 2 out of 10 plants in the inoculated area 3 days later, and 4 out of 10 plants in the inoculated area 6 days later. On the other hand,
In the control plot, systemic disease symptoms were observed in 9 out of 10 plants.

2. The damaged parts of the stems caused by the application of the insect repellent were almost completely repaired after two weeks. Moreover, no phytotoxicity was observed on the leaf surface.

Applicant: Kureha Chemical Industry Co., Ltd. Agent Miya 1) Hirotoyo

Claims (1)

[Scope of Claims] ■. A substance having control activity against plant virus diseases;
A plant virus disease control agent formed by molding a product supported by gluten or a mixture of gluten and other polymeric substances into a molded article having a shape suitable for insertion into a plant body. 2. The control agent according to claim 1, wherein the substance having control activity against plant virus diseases is a culture of filamentous fungi or a substance collected therefrom. 3. Claim 1, wherein the proportion of gluten in the mixture of gluten and other polymeric substances is 35% by weight or more
Pesticides listed in section. 4. The pest control agent according to any one of claims 1 to 3, wherein the molded product is a rod-shaped body with at least one tip having an acute angle.