JPH11246311A - Agent for controlling rust - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject control agent having high safety for environments, holding the effect for a long period and capable of specifically inhibiting the germination of aecidiospores as one of the causes of the rust by adding a specific compound as an active ingredient. SOLUTION: This agent for controlling rust contains a compound of formula I R is a group of formula II [(n) is 4, 6 or 8], a group of formula III [(m) is 4 or 6] or a group of formula IV} as an active ingredient. The compound of formula I can be obtained, for example, by its isolation and purification from the dry roots and stems of Zingiber offcinale Rosc, a plant of the family Zingiberaceae, or by its chemical synthesis. The rust control agent is obtained by mixing the compound of formula I, if necessary, with a carrier, a surfactant, a dispersant, an auxiliary, etc., and subsequently processing the mixture into a formulation such a water-dispersible powder, an emulsion, a dust or granules. The compound of formula I is preferably mixed in an amount of 0.1-80% based on the formulation. The control agent is preferably used at a dose of 0.1-5,000 g (as the active ingredient) per 10 are in the case of the dust or the granules.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a rust control agent. More specifically, the present invention relates to a rust control agent which is highly safe for the environment, has a long-lasting effect, and specifically inhibits germination of rust spores which cause rust.

[0002]

2. Description of the Related Art One of the major obstacles in cultivating crops is rust disease. Rust fungus (rus
t) is a pathogenic bacterium which causes rust on plants, and belongs to the order of Basidiomycetes and Rust in taxonomical terms. Rust fungi are a huge group of bacteria with about 150 genera and about 6000 species reported all over the world. All of them are phytopathogenic fungi because they cannot grow without parasitizing plants. . Rust fungi are known to cause disease on important crops and flowers.

[0003] The life cycle of rust fungi is very complex, and is a polyplastic bacterium, which recycles the host. Due to these characteristics, a method of controlling the rust fungus has been practiced in which one of the two types of hosts, which has less economic value (intermediate host), is eliminated to cut off the life cycle of the rust fungus. Rust fungi, on the other hand, form spores called rust spores, uredospores, basidiospores, sporophytes and winter spores, and the disease is transmitted.Of these spores, rust spores and uredospores are highly resistant and long-lasting. Dispersion of distance is possible.

[0004] In contrast, basidiospores are weakly resistant and die during long-range flying. Therefore, when the type of spores infecting economically useful crops is basidiomycetes or sporophytes, it is effective to suppress the occurrence of rust by removing the intermediate host near the cultivation area as described above. . In practice, for example, in controlling pear scab and apple scab, measures are taken not to plant juniper, an intermediate host of these causative fungi, near a field. However, rust spores and uredospores are highly resistant, overwintering, and capable of flying over long distances. Therefore, the above method is ineffective for crops that are infected with rust spores and uredospores and cause disease.

[0005] Another method of controlling naturally includes the use of a fungicide. After the rust germinates, it penetrates into the host tissue and establishes a parasitic relationship. Therefore, effective bactericides for controlling rust can be considered to be highly permeable. However, it is considered that these fungicides naturally have high persistence, and they are used for crops where agricultural chemicals are sprayed, that is, leaves or stems, which are the sites where rust fungus is parasitically infected, are edible. Is difficult. On the leaves of many plants,
It is thought that a complex microflora exists to promote plant growth and prevent the invasion of other pathogens. Generally, fungicides having antibacterial activity have low selectivity and inhibit the growth of many useful bacteria. In addition, breeding of resistant varieties by breeding is mentioned, but plants having a gene resistant to rust are limited to a part of wheat and the like which are being bred, and many plants still do not. No gene has been found.

[0006]

From the above circumstances, it has been desired to develop a highly safe, rust-controlling agent.
At present, no effective compound has been found as a single compound. Therefore, an object of the present invention is to provide a rust control agent which is highly safe for the environment, has a long-lasting effect, and specifically inhibits the germination of rust spores, which is one of the causes of rust. is there.

[0007]

Means for Solving the Problems In order to solve the above-mentioned problems, the present inventors sprayed a composition having a rust spore germination inhibitory activity on a rust bacterium before the rust bacterium established a parasitic relationship with a host. After diligent studies to prevent the process of rust and to control rust, we found that some crude drugs such as ginger used as a raw material of Chinese herbal medicine found rust spore germination inhibitory activity of rust fungus and applied for a patent. (Japanese Patent Application No. 8-289453)
Was done. As a result of further research, the compounds contained in ginger and dried ginger, as well as in ginger, which is usually provided as a food, were found to have the activity of specifically inhibiting the spore germination of rust bacteria, especially uredospores. The invention has been completed.

That is, the present invention is as follows. (1) Equation 1

Embedded image Wherein R represents Formula 2, Formula 3 or Formula 4. ]

[0009]

Formula 2 (However, n represents 4, 6, or 8)

[0010]

Formula 3 (However, m represents 4, 6)

[0011]

Formula 4 It is a rust control agent which contains the compound represented by these as an active ingredient.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail.
To specifically explain the compound, in Formula 1, a compound in which R is Formula 2 and n is 4 is 6-gingerol (6-Gingero).
l), the compound in which n is 6 is 8-gingerol (8
-Gingerol), the compound in which n is 8 is called 10-gingerol (10-Gingerol). Also, in Equation 1,
A compound in which R is Formula 3 and m is 4 is referred to as 6-Shogaol, and a compound in which m is 6 is referred to as 8-Shogaol. Further, in Formula 1, the compound in which R is represented by Formula 4 is referred to as 10-Gingerdione. Note that, in Equation 1,
The compound in which R is represented by the formula 3 has a stereoisomer because of a double bond in a side chain, and includes all of these stereoisomers.

The above-mentioned compounds are known compounds, for example, Zingiber offci, a plant of the family Zingiberaceae.
nale Rosc.) obtained by performing operations such as isolation, purification, and synthesis from the dried rhizome by known methods described in literatures and the like. Moreover, you may use what is marketed. These compounds may be used in combination of two or more kinds.

The rust control agent of the present invention has a particularly excellent inhibitory activity on the germination of rust spores, especially euspores, which cause rust, and the rust caused by a wide variety of rust fungi. Useful for controlling diseases. For example, in the rust fungus family (Pucciniaceae), rust fungi belonging to broad bean and pea (Uromyces fabae), rust of green beans (Uromyces appediculatus), rust fungus of sparrowpea (Uromyces alopecuri), red scab of pear ( G
ymnosporangium haraeanum), apple scab (Gymnos
porangium yamadai), wheat rust (Puccinia tr)
iticina), yellow rust of wheat and barley (Puccinia gl
umarum), black rust of wheat, barley and oat (Pu
ccinia graminis), crown rust of oat (Puccinia co
ranata), brown rust of rye (Puccinia dispers
a), corn rust fungus (Puccinia sorghi), leek and onion rust fungus (Puccinia alli), green onion rust fungus (Puccinia porri), chrysanthemum black rust fungus (Puccinia chry)
santhemi), chrysanthemum rust fungus (Puccinia horiana), sera rust fungus (Puccinia oenanthes-stoloniferae), peppermint rust fungus (Puccinia menthae), and the like. , Soybean rust (Phakopsora pachyrhizi), fig rust (Phakopsora nisidana), cotton rust (Phakop
sora gossypii), grape rust fungus (Phakopsora ampelo)
psidis), rust of jujube (Phakopsorazizyphi-vulgar)
is), flax rust fungus (Melmpsora lini) and the like,
Rust fungi belonging to the column rust fungi (Coleosporiaceae) include perilla rust fungus (Coleosporium plectranthi). In addition, the rust control agent of the present invention does not show an effective inhibitory activity against spore germination of pathogenic bacteria other than rust fungus, and hardly causes phytotoxicity to target crops and flowers, and is safe. Is high.

As the rust control agent of the present invention, the compound itself may be used, but usually, if necessary, a carrier, a surfactant, a surfactant, and the like, as long as the rust control effect of the present invention is not impaired.
A dispersant, or an auxiliary agent, etc. is appropriately compounded, and in a conventional manner
For example, it can be formulated and used in wettable powders, emulsions, powders or granules. These formulations may be diluted to an appropriate concentration and applied or used directly.

The compounding ratio of the active ingredient is selected as required, but it is usually appropriate in the range of 0.1 to 80% based on the preparation. The application rate of the rust control agent of the present invention varies depending on the type of the compound to be used, the target disease, the degree of damage, the environmental conditions, the dosage form to be used, and the like. Is 10 as an active ingredient
0.1 to 5000 g per are, preferably 0.5 to
It is better to choose from a range of 1000 g. When used as a final liquid such as an emulsion or a wettable powder, 0.1%
It is good to choose from the range of 10000-10000 ppm, preferably 1-5000 ppm.

[0017]

EXAMPLES The present invention will be described in detail below with reference to examples, but the present invention is not limited to these examples. (Test Example 1) Test for controlling onion rust of welsh onion A germination inhibition test of a test compound on germination of uredospores of rust of green onion was performed. Collection of spores of allium rust fungus on leek In a green onion cultivation field, collect the leaves of the leaf onion plant where the rust fungus has occurred near the upper part of the disease outbreak, wash it well under running water, and remove various bacteria attached to the surface Was removed. this,
The cells were placed in a 90 mm Petri dish and cultured at 20 ° C. for 16 hours under light irradiation conditions. Three days after the start of the cultivation, a uredospore bank caused by the leeks rust appeared on the leaf surface, and uredospores were obtained.
The uredospores were subjected to subsequent tests.

Germination Inhibition Test On a sterilized cover glass, 10 μl each of a test solution containing a low-melting point agarose having a final concentration of 0.6% and a test compound in a 1/2 concentration of Zapec inorganic salts (pH 6.0) was added.
Each of them was added dropwise and solidified at room temperature. Hereinafter, this culture medium is referred to as a germination bed. In each test plot, the test compound was prepared at a final concentration of 50 μg / ml and added.

Further, 100 to 200 euspores of the green onion rust prepared by the above method were inoculated on these germinated beds using a brush. After these operations were completed, the cover glass was turned downward for each germination bed, and fixed to the mouth of a mini petri dish (18 mm in diameter) with paraffin.
The culture was performed in the dark. After 17 hours of culture, the cells were examined under a microscope, and the number of germinated spores and the number of ungerminated spores were counted using a counter. Germinating spores were obtained by elongating a germinating tube longer than the major axis of the spores.

In each plot, approximately 100
Observation was performed on up to 200 spores, and the germination inhibition rate was calculated according to the following equation by comparing and culturing with a germination bed containing no test compound. Germination inhibition rate (%) = {(AB) / A} × 100 A: Germination rate in test plot cultured with no test compound added B: Germination rate in test plot cultured with test compound addition It is shown in Table 1 below.

[0021]

[Table 1]

As is evident from Table 1, the rust control agent of the present invention has an excellent inhibitory activity on the germination of uredospores of the green onion rust fungus. (Test Example 2) Test for control effect of perilla rust A germination inhibition test of a test compound against euspore germination of perilla rust was performed. Collection of perilla rust spores of perilla The perilla leaves growing in the field and near the perilla leaves infected with perilla rust were collected and thoroughly washed under running water to remove various bacteria attached to the leaf surface. This sample was placed in a 90 mm petri dish and cultured at 20 ° C. for 16 hours under light irradiation conditions.
Euspores appeared on the back of the leaves 3 to 7 days after the start of the culture, and euspores were obtained. The uredospores obtained by the above operation are inoculated on perilla leaves collected from a perilla plant newly grown in a constant temperature room, placed in a 90 mm petri dish, and placed at 20 ° C.
The cells were cultured for a period of time under light irradiation. After 14 days from the start of the culture, formation of a new uredospore bank on the back of the leaf was observed, and fresh uredospores of Perilla rust fungus were obtained. The uredospores were subjected to subsequent tests.

Germination Inhibition Test A germination inhibition test was carried out using the same method as shown in Test Example 1. In the germination bed of each test plot, 100
Euphospores of ~ 200 L. rust fungi were inoculated. The results obtained are shown in Table 2 below.

[0024]

[Table 2]

As is clear from Table 2, the rust control agent of the present invention has an excellent inhibitory activity on the germination of uredospores of Perilla rust.

Although the rust control agent of the present invention has a different germination inhibition rate, other rust fungi such as rust of broad bean and pea and rust of kidney bean are included in the rust fungi belonging to the family of rust fungi. , Rust fungus of the sparrow, Pear scab of pear, scab of apple, rust of wheat, yellow rust of wheat and barley, black rust of wheat, barley and oat, crown rust of oat,
Rye brown rust fungus, corn rust fungus, green onion red rust fungus, chrysanthemum black rust fungus, chrysanthemum white rust fungus,
Rust fungi belonging to the stratiform rust fungus family such as rust fungus of seri, mint of peppermint, soybean rust, fig rust, cotton rust, grape rust, jujube rust, flax rust The same effect can be expected for rust fungi such as fungi.

(Test Example 3) Test for inhibition of germination of test compound on germination of oyster mushroom basidiomycetes Pleurotus (Pleurotus o.) Belonging to the same basidiomycetes as rust fungus
A germination test was performed on basidiospore germination of Streatus). Collection of oyster mushroom basidiomycetes Basidiomycete oyster mushrooms were purchased from a commercial product, and a large amount of mature basidiomycetes were collected using the spore print method and subjected to a test. In detail, a fully matured (opened umbrella) fruit body of the purchased oyster mushroom body was cut off from the handle portion, placed on a floor with the umbrella face down in a sterile petri dish, and allowed to stand at room temperature for 24 hours. Then, the umbrella was carefully removed, and the basidiospores collected on the lower surface of the petri dish were collected and used in the following tests.

Germination Inhibition Test Low-melting point agarose having a final concentration of 0.6% was added to a 1/2 concentration of Zapec inorganic salts (pH 6.0) to form a germination bed.
In each test plot, test compound was added at a final concentration of 50 μg / ml.
Was added to these germinated beds. Each germination bed was dropped on a sterilized cover glass by 10 μl each and solidified at room temperature. 100-500 oyster mushroom basidio spores prepared using the above method were inoculated on this, placed on a sterile petri dish containing filter paper moistened with sterile water, cultured at 25 ° C. in the dark for 3 days, and then observed under a microscope. The number of germinated and ungerminated spores was counted. The inhibition rate was calculated according to Test Example 1. The results obtained are shown in Table 3 below.

[0029]

[Table 3]

From the results shown in Table 3, the rust control agent of the present invention was not found to effectively inhibit spore germination of Pleurotus ostreatus, and the inhibitory activity was specific to spores of rust fungus. It was found to be safe without affecting fungi.

[0031]

As described above, since the rust control agent of the present invention contains a naturally derived compound as an active ingredient, it is extremely safe for the environment, has a long-lasting effect, and has a rust effect. It has excellent inhibitory activity against the germination of fungal rust spores, uredospores, basidiospores, sporophytes and winter spores, especially urespores.

Claims (1)

[Claims] (1) Formula 1 Wherein R represents Formula 2, Formula 3 or Formula 4. Formula 2 (Where n represents 4, 6, or 8). (Where m represents 4, 6) Formula 4 A rust control agent comprising a compound represented by the formula (1) as an active ingredient.