JP2007099762A - Agent for preventing rice plant seed disease and method for controlling the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an agent for preventing Bacterial brown stripe disease free from environmental pollution, having preventing effect to disease damage of Bacterial brown stripe disease or a rice plant seed disease and to provide a method for preventing the same. <P>SOLUTION: The problem is solved by making a rice-plant in contact with the preventing agent comprising, as the active ingredient, the calcined calcium obtained by calcining shells and having an antagonistic effect on the Bacterial brown stripe disease. Pathogenesis of the Bacterial brown stripe disease is suppressed by utilizing the calcined shells in application of the agent and method of the invention. The preventing agent of the invention has antibacterial and sterilizing properties originated from organic materials belonging to itself and a porous structure retaining essential skeleton structure of the shells, and not induces environmental pollution and drug-induced disease by high pH like conventional chemical preventing agent. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a control agent and a control method for controlling rice brown stripe diseases.

  Currently, plant diseases, for example, rice seed diseases, idiotic seedling disease (pathogenic fungus name: Gibberella fujikuroi), seedling blight disease (pathogenic fungus name: Burkholderia plantarii), and bacterial blight disease (pathogenic fungus name: Burkholderia glumae), It is a disease that occurs in rice seedling boxes and is a plant disease that causes serious problems during rice seedling raising.

  On the other hand, rice brown disease (pathogen: Acidovorax avenae subsp. Avenae), which is the same rice seed disease, is a seed-borne bacterial disease that occurs during rice seedling and causes enormous diseases. Raising seedlings has been generated by the introduction of warm seedlings by box seedlings. Symptoms of this rice brown streak disease are that the seedlings that are being nurtured turn into streaks, the seedlings bend, and eventually die, resulting in great damage. For the purpose of controlling such plant diseases, control is also carried out in combination with chemical agents having antibacterial activity such as inorganic copper, oxolinic acid and kasugamycin.

  As conventional techniques regarding the control of these rice seed diseases, in Patent Document 1 and Patent Document 2, alkali metal or alkaline earth metal carbonate or hydrogen carbonate such as calcium carbonate, alkali metal or alkaline earth metal water is used. The use of oxides is disclosed.

At present, mineral alkali metal or alkaline earth metal carbonates or hydrogen carbonates such as calcium carbonate (CaCO ₃ ) obtained from marble and limestone are used as additives in foods, pharmaceuticals and health supplements. However, these are registered as fertilizers in the agricultural field and widely used as soil conditioners for adjusting the pH of the soil and calcium carbonate agents for the purpose of mitigating phytotoxicity of inorganic copper preparations.

  As conventional peripheral techniques for controlling rice seeds with a combination of a calcium carbonate agent and a chemical agent, in Patent Document 3 and Patent Document 4, carbonates such as calcium carbonate and an agricultural chemical having antibacterial activity are used. It has also been proposed to use it as a rice seed fungicide by combining certain chemical agents such as ipconazole, benomyl, and prochloraz.

  On the other hand, in recent years, a technique for applying the knowledge of the natural world in which the mechanism of the composition, structure, component, etc. related to the birth, growth, and extinction of living organisms functions organically has been attracting attention. For example, microorganisms are used as active ingredients and are being applied to agricultural chemicals. However, these microbial pesticides have excellent environmental properties, but many of them are expensive.

  Therefore, in recent years, a technique for applying organic and inorganic components contained in animal shells to soil disease control materials has attracted attention. In Patent Document 5, chitin contained in animal shells of salmon and shrimp. Disclosed is a soil disease control method for the purpose of fixing actinomycetes, which produce the chitase enzyme separated from the contained organic matter on the soil and the like, in the soil.

  On the other hand, even with the same animal shells, shellfish shells such as scallops, abalone, oysters, and sea bream have an output of about 1 million tons per year, and many are landfilled as waste. Since it is about 1 million tons, the amount of waste is enormous. Therefore, with the aim of reducing the amount of waste, effective research measures have been considered in research institutions and companies including local governments.

  These shells are composed of 99% calcium carbonate and 1% organic (differs depending on the structure), have extremely high toughness (similar to plastic) and are excellent natural composite materials. A three-layered shell, which uses carbon dioxide dissolved in the sea as a carbon source, forms calcium carbonate from calcium in the sea, forming a unique structure.

  When shells such as scallops are fired, generally, calcium carbonate, which is a component thereof, is converted into calcium oxide (CaO). Calcined calcium obtained by calcining shells (calcined calcium is mainly calcined shells such as scallops or crabs at high temperatures, so that decarboxylation (removing carbon dioxide) gradually proceeds from the main component calcium carbonate. Natural calcium oxide (CaO), or calcium oxide and calcium carbonate, hereinafter referred to as “calcined calcium” in the present specification) is calcined at, for example, 500 to 1200 ° C. Thus, the calcium carbonate and organic matter inside the shell are baked and further decarboxylated, and finally calcium oxide is baked. When the calcination temperature is increased, almost all is converted to calcium oxide, but when the calcination temperature is low, a part of it is changed to calcium oxide, but the rest remains as calcium carbonate. It has been known for a long time that the alkali component of calcium oxide contained in the calcined calcium and the porous structure of the shell itself increase the disinfecting effect, the deodorizing effect and the antibacterial effect.

  Among these, application to seed diseases has recently attracted attention. In Patent Document 6, a mixture of calcined calcium, peroxocarbonate, and coating agent is used to coat the seed surface by film coating or coating granulation. Thus, a method for controlling seed diseases such as cabbage and spinach is disclosed.

As a method for controlling a specific disease of rice by using a microbial pesticide, for example, in Patent Document 7, Patent Document 8, and Patent Document 9, Pseudomonas bacteria are cultivated with bacterial wilt of rice, bacterial wilt of rice, and rice idiot. It is disclosed to be used for seedling diseases and the like. In addition, as a conventional technique related to the control of rice brown stripe disease, which is the target disease of the present specification, Patent Document 10 has a high antagonistic ability against the pathogenic Pseudomonas avenae bacteria that cause brown stripe disease in rice seedlings. A control agent and a control method containing Bacillus bacteria as an active ingredient are disclosed.
Japanese Patent Laid-Open No. 9-272111 JP 2004-262926 A JP-A-5-221812 JP-A-5-238911 JP-A-7-2614 JP 2004-292354 A JP-A-11-302120 JP 2002-017343 A JP 2003-261409 A JP 2002-080316 A

  As the seed disease control method, conventionally, the control agents known in Patent Document 1 and Patent Document 2 can be supplied in a large amount at a low price, and these are used to attempt disease control. . However, although there is a control effect under the occurrence of small to moderate diseases, it cannot be said that the control value is sufficient under conditions with high disease occurrence, that is, under the occurrence of wrinkles.

  Further, in the method of Patent Document 6, seed disease can be controlled by coating the seed surface of the crop with a coating material containing calcined calcium. However, as in Patent Document 1 and Patent Document 2, the control effect under the occurrence of wrinkles. Was not so expensive.

  Then, the subject of this invention is providing the control agent and control method which have a high control effect with respect to a rice seed disease, especially a brown streak disease, and there is no environmental pollution as an object for rice seed disinfection. Therefore, for the control of these diseases, it is hoped to develop a control agent that has a high control effect and that is free from environmental pollution such as water pollution, which has been a problem with conventional seed disinfectants, and that does not burden the economy. It was rare.

  The present inventors have intensively studied to solve the above problems. As a result, they found that calcined calcium obtained by calcining shells such as scallops, abalone, oysters, and oysters has a controlling effect on rice brown stripe disease.

  Although the cause is not clear, shells such as scallops, abalone, oysters, and oysters used in the present invention are characterized by organic matter and a skeletal structure (multilayer structure, porous structure) as compared with a fired mineral. The unique structure and specific functions of the calcined calcium of the shell itself, such as the multi-layer and porous structure, exhibit high antibacterial properties, antibacterial maintenance properties, and long-lasting properties. It is presumed that the control effect was obtained by using it for seeds.

  About the disease used as the object of this invention, the method currently disclosed by patent document 1 and patent document 2 is mentioned as mentioned above. However, even if these mineral alkali metal or alkaline earth metal carbonates or oxides are used for rice brown disease, the desired effect is not obtained, and the control effect is small or the control effect cannot be obtained. (See comparative example of this application). In addition, the method using the microbial pesticide disclosed in Patent Document 10 has a remarkable control effect and is a useful method, but is often expensive.

  However, the present inventors have found that there is a particularly favorable effect when calcined calcium, which is economically inexpensive and easily available, is used for rice brown stripe disease.

  Moreover, as disclosed in Patent Document 6, as a seed disease control agent, a shell component and a mineral such as a covering material have been mixed and used instead of the shell component alone. However, the inventors of the present invention have obtained knowledge that control can be carried out even if baked calcium of shells is used alone without using a mineral such as a covering material for rice seeds.

  Furthermore, the present inventors also obtained the knowledge which has a high control effect with respect to rice brown stripe disease by using the calcined calcium which adjusted calcium carbonate and calcium oxide to the specific component ratio (%).

  Thus, there is no example which showed the control effect by using calcined calcium for a rice seed, and also it was not known until now that there was a control effect by using alone with respect to a rice seed.

  That is, the present invention relates to a rice brown streak disease control agent containing calcined calcium obtained by calcining shells as an active ingredient, which has antagonistic activity against rice brown streak disease of rice seeds, and rice seeds thereof. It is a method for controlling rice brown stripe disease of rice seeds, characterized in that it is brought into contact.

  As a control agent and control method for controlling rice brown stripe disease in the present invention, it is possible to easily control a specific disease of rice economically advantageously, environmentally friendly, by using a baked shellfish. I can do it.

  Furthermore, the use of the control agent of the present invention does not cause environmental pollution like existing chemical agents, and does not cause phytotoxicity due to high pH. Moreover, since it does not cause the fall of the control effect by the appearance of agrochemical resistant bacteria, it is very useful.

  Hereinafter, the present invention will be described in detail. The present invention relates to a rice brown rice disease control agent containing as an active ingredient a calcined calcium obtained by baking shells, which has antagonistic activity against rice brown stripe disease of rice seeds, and rice seed rice using the same. This is a method for controlling brown stripe disease.

  Although detailed firing conditions for the shell used in the present invention will be described later, there is no particular limitation as long as the component before firing contains a calcium carbonate as a main component, specifically, red shellfish, clams, scallops. Examples include shellfish, abalone, oysters, oyster shells, mussels, sakura mussels, turban shells, swordfish, snails, snails, crocodiles, clams, and clams.

  Shells that can be obtained regularly at shellfish farms and processing plants are preferred. Among the above shells, red shellfish, scallops, abalone, oysters, oyster shellfish, Triggery, clam, turtle shell Is preferably used.

  Among these, scallop shells, abalone, oysters, and oyster shells are particularly preferable because they can be obtained more easily and in large quantities. Specifically, in Example 1, it is one of preferred embodiments to use calcined calcium obtained by calcining scallops and abalone shells.

  These shells may consist of one type of shell or a mixture of two or more types of shells. However, it is particularly preferable to use one type of shell because processing is easy.

  The calcined calcium used in the present invention is a calcium oxide (CaO) obtained by gradually decarboxylation (removing carbon dioxide) by firing a shell whose main component before firing is calcium carbonate. Or it contains calcium oxide and calcium carbonate. By firing, calcium carbonate, which is the main component (about 99%) before firing, is gradually converted to calcium oxide, and at the same time, firing of about 1% of organic matter contained in the shell before firing proceeds simultaneously. .

  The chemical composition of the calcined calcium used, that is, the ratio of calcium carbonate and calcium oxide and each component will be described below.

  About the component ratio (weight%) of calcination calcium, it changes greatly with calcination temperature and calcination time.

  Here, the results of measurement of calcined calcium having different component ratios (% by weight) by thermogravimetric-differential thermal analysis (TG-DTA) are shown below as Table 1 (in Table 1, calcined calcium A, C, D and E are calcined calcium obtained by appropriately adjusting the calcining temperature and calcining time).

Usually, for the component ratio (wt%), calcium carbonate (CaCO _3): calcium oxide (CaO) = 1: 99 to 99: ones can be used 1. Among these ranges, the use of calcined calcium in the range of calcium carbonate: calcium oxide = 50: 50 to 99: 1 is preferably used because it can suitably control the brown stripe disease.

  Furthermore, among these ranges, using calcined calcium adjusted to a range of calcium carbonate: calcium oxide = 70: 30 to 99: 1 can obtain a high control effect against rice brown stripe disease. preferable.

  The ratio of these calcium carbonate and calcium oxide and each component differs depending on the firing temperature and firing time, and can be adjusted as appropriate by those skilled in the art.

In the present invention, calcined calcium is preferably used in a mixed state of calcium carbonate and calcium oxide. However, calcium oxide has a high hygroscopic property, and is partially hydrated to produce calcium hydroxide (Ca (OH) ₂ However, there is no problem in performance. For this reason, in the present invention, calcined calcium in which a calcium hydroxide component is mixed in addition to calcium carbonate and calcium oxide can be used as the calcined calcium component.

  In addition, the calcined calcium used in the present invention is not particularly limited, but a calcined shell such as scallop and then ground and powdered can be used. Moreover, you may bake after grind | pulverizing.

  On the other hand, a commercially available powdered product obtained by pulverizing calcined calcium can be used, and can be appropriately selected by those skilled in the art.

  Moreover, when manufacturing calcination calcium, it calcinates normally in the temperature range of 500-1200 degreeC. Among these temperature ranges, in the present invention, the temperature range is preferably 600 to 1200 ° C, more preferably 600 to 1100 ° C.

  There is no restriction | limiting in particular about baking, For example, common baking apparatuses, such as a rotary kiln and an open fire burner, can be used. The firing time varies depending on the firing temperature, but can be appropriately adjusted by those skilled in the art in order to obtain a preferable ratio of the above-mentioned calcined calcium.

  The calcined calcium is usually used by pulverizing itself. The particle size at the time of pulverization varies depending on the baking treatment and processing method, and is not limited, but is usually pulverized to 2 to 100 μm, preferably 2 to 70 μm, more preferably 3 to 45 μm. Here, the particle size means the average length (average diameter) of the longest portion and the shortest portion of one pulverized calcined calcium powder. There is no particular limitation on the pulverization method, and a general pulverizer can be used.

  As a specific example of the calcined calcium used in the present invention, for example, commercially available scallops are used as shells, and a high-temperature calcined product (trade name CAI-I, particle size 5 μm type) And 15 μm type (manufactured by Japan Natural Materials Co., Ltd.) and scallop pulverized product (trade name CAI-V, particle size 5 μm type and 15 μm type, manufactured by Japan Natural Materials Co., Ltd.), also scallop baked product Pulverized product (trade name MC-H (Magnacaps), particle size 5 μm type, manufactured by Asada Shokai Co., Ltd.), abalone shell as a shell, and pulverized product of the fired product (trade name MC-A) (Magnacaps), particle size 5 μm type, manufactured by Asada Shokai Co., Ltd.). Other similar baked products are, for example, manufactured by Kawai Co., Ltd. (trade name “Shell baked calcium HD”), manufactured by Step Co., Ltd., manufactured by Chaflows Corporation (trade name “Shell White”), etc. There is.

  Next, a method for controlling rice seed diseases using the control agent of the present invention will be described. In general, rice seedlings are soaked in water for a certain period of time (seeding). After the seed pods have sufficiently absorbed water, they are soaked in water at around 30 ° C for 1 to 2 days, and then germinated. Sowing seedlings in seedling soil, seedling boxes filled with seedling soil, seed beds, etc.

  The control agent of the present invention is a control agent for controlling rice brown stripe disease that can be used widely without any problem of phytotoxicity and without limitation of use time. Specifically, the control agent of the present invention is obtained by immersing rice seed pods before soaking, at the time of sowing or at the time of germination, or before sowing, at the time of sowing, before sprouting or before sowing in the diluted solution of the control agent of the present invention. After the rice seed pods are treated with wet powder or sowed, the diluted solution of the control agent is poured into the soil and used.

  As described above, the present invention is economically advantageous because it is not necessary to use a component such as a coating material for seeds. Moreover, the temperature of the dilution liquid in the case of immersing the rice seed meal in this control agent dilution liquid at the time of soaking or germination is 15 ° C to 35 ° C, preferably 20 ° C to 35 ° C. Moreover, regarding the time to process, it processes from instantaneous to 48 hours, Preferably it is 1 to 24 hours.

  In the case of using the above-described method of the present invention, the control agent comprising calcined calcium obtained by calcining shells as an active ingredient according to the present invention, for example, in the case of immersion treatment, the calcined calcium concentration in the immersion liquid is usually 0.01% by weight to 1% by weight (dilution factor is 10,000 to 100 times), preferably 0.1% to 1% by weight (dilution factor is 1000 to 100 times), more preferably 0.1% to 0%. .8% by weight (as a dilution factor of 1000 to 125 times), calcined calcium liquid (refers to a liquid containing suspended or emulsified calcined calcium formed by mixing calcined calcium with water) The same shall apply hereinafter).

  On the other hand, in the case of wet dressing treatment, rice seed pods that have been soaked or germinated can be drained, and then mixed with calcined calcium and then sown. For example, the calcined calcium may be 0.1 g to 10 g, preferably 0.5 g to 5 g based on 100 g of rice seed meal.

  In addition, in the case of soil irrigation, the soil can be soaked with an aqueous solution such as calcined calcium. For example, 50 to 500 ml of diluted solution obtained by diluting calcined calcium 10 to 1000 times, preferably 50 to 500 times, per soil in a seedling box (the size can be appropriately selected, for example, 30 × 60 × 3 cm) is put in soil. Note.

  Although calcined calcium may be used as it is, it can be used by mixing with mineral powder as used in ordinary agricultural chemicals. Mineral powders include talc, calcium carbonate, and diatomaceous earth. As will be described later, the amount of the mineral powder added may be determined by the dilution factor having a controlling effect as shown in the examples. For example, it is possible to use a mixture of calcined calcium and mineral powder having a controlling effect with a water suspension obtained by diluting only calcined calcium 500 times. In this case, for example, if 40 parts by weight of the calcined calcium and 60 parts by weight of the mineral powder are mixed, the resulting mixed powder may be diluted 200 times to form an aqueous suspension.

  However, in the present invention, the calcination of calcined calcium can be achieved by subjecting the rice seeds to the above-mentioned treatment using the calcined calcium solution diluted with water as it is or without being mixed with mineral powder. Even if the product is not mixed with the above-mentioned mixing powder, it has a controlling effect.

  For example, in the present invention, as shown in Example 1, use of a calcination product of calcined calcium as a liquid diluted with water without mixing with mineral powder has an effect of controlling rice seed diseases. Therefore, this is one of the particularly preferred embodiments.

  When the calcined calcium is dissolved in water by about 0.2% by weight, the pH becomes 12 to 13 and shows strong alkalinity. Compared with quick lime obtained by calcining the mineral calcium carbonate, the reactivity is low, but due to its unique multi-layered / porous structure, the retention of alkali components is increased, and it is effective for a long time Persists. Furthermore, there is a feature that no phytotoxicity occurs due to high pH.

  Further, it is extremely useful because it does not cause a decrease in the control effect due to the appearance of pesticide-resistant bacteria found in conventional chemical agents.

  In addition, calcined calcium is added to food as a source of calcium itself, sprayed with several percent by weight aqueous solution of calcined calcium, and used to control pathogens, bacteria, mold, etc. It is also used for cleaning residual pesticides in vegetables and fruit trees. In addition, it is also used as an addition of wall materials such as plaster for architectural purposes. It is also applied to pharmaceuticals. As calcined calcium is not restricted by the United Nations Food and Agriculture Organization (FAO) and the World Health Organization (WHO) Joint Food Additives Expert (JECFA), the daily intake of food additions is not restricted. There is no problem with safety.

  EXAMPLES Next, examples will be shown, but the present invention is not limited to the following examples.

Suppressing effect of calcined calcium of shellfish on rice brown streak disease Sintered calcium of scallops A, B, C, D, E, and F (5 μm particle size type, B is trade name “CAI-V” F) is a product name “CAI-I” (manufactured by Nippon Natural Materials Co., Ltd.) diluted 200 times or 500 times with water, and the calcined calcium concentration is 0.5% by weight, 0.2% by weight. A calcined calcium solution was prepared so that Rice brown streak contaminated rice bran (variety: Koshihikari) was added to this solution, and pre-soaked for 24 hours at 15 ° C. or immersed for 24 hours at 32 ° C. during germination. Others were seeded after soaking and germination according to conventional methods, and seedlings were raised in a glass greenhouse for 2 weeks.

  The results are shown in Tables 2 and 3. The rice brown streak test was evaluated by calculating the disease severity from the seedling disease severity.

Disease index 5: Withering, 3: Disease and plant height is less than 1/2 of healthy, 1: Disease and plant height is 1/2 or more of healthy, 0: Healthy disease severity = 100 × {Σ (index value) × (each Number of solids corresponding to the index)} ÷ {5 × (number of surveyed seedlings)}
Control value = 100 × {(morbidity in untreated area) − (morbidity in treated area)} ÷ (morbidity in untreated area)

[Comparative Example 1] Disease control effect of calcium carbonate (CaCO ₃ ) on rice brown streak disease Calcium carbonate was diluted 200 times and 500 times with water to give 0.5 wt% and 0.2 wt%. In the same manner as in Example 1, the pre-soaking immersion treatment or the germination immersion treatment was performed in the same manner as in Example 1.

  The results are shown in Tables 4 and 5. The rice brown streak test was evaluated by calculating the disease severity and control value from the disease severity of the seedlings. The disease severity and the control value were calculated in the same manner as in Example 1.

As shown in Table 4 and Table 5, in the case of calcium carbonate, it can be seen that the control effect is lower than when the calcined calcium treated area of Example 1 is used.
[Comparative Example 2] Disease prevention effect of quick lime (CaO) on rice brown streak disease Quick lime (CaO) is diluted 200-fold and 500-fold with water so that it becomes 0.5 wt% and 0.2 wt%, respectively. Except for the preparation of the liquid, the pre-soaking immersion treatment or the dipping treatment during germination was performed in the same manner as in Example 1.

  The results are shown in Tables 6 and 7. The rice brown streak test was evaluated by calculating the disease severity and control value from the disease severity of the seedlings. In addition, about the disease severity and the calculation method of a control value, it carried out similarly to Example 1. FIG.

  As shown in Tables 6 and 7, it can be seen that quick lime (CaO) also has a lower control effect than when the calcined calcium-treated section of Example 1 was used.

Claims (8)

A control agent for controlling rice brown stripe disease, comprising as an active ingredient calcined calcium obtained by baking shells, which has an antagonistic activity against rice brown stripe disease of rice seeds. The control agent according to claim 1, wherein the shells are scallops, abalone, oysters, and crabs. It is characterized by performing calcined calcium by using a component ratio (%) of calcium carbonate (CaCO ₃ ) and calcium oxide (CaO) in the range of CaCO ₃ : CaO = 50: 50 to 99: 1. The control agent according to claim 1 or 2. A method for controlling rice brown stripe diseases of rice seeds, comprising bringing the control agent according to any one of claims 1 to 3 into contact with rice seeds. A method for controlling rice brown stripe diseases of rice seeds, comprising mixing the control agent according to any one of claims 1 to 3 with water to form a calcined calcium solution and immersing the seeds in rice seeds. 6. The method according to claim 5, wherein the dipping treatment is performed by immersing the calcined calcium solution in a rice seed bran before soaking, at the time of soaking or at the time of germination. The method according to claim 5 or 6, wherein the method is carried out by immersing the rice seed meal in the calcined calcium solution for an instant of 48 hours. The method according to any one of claims 5 to 7, wherein the calcined calcium solution is prepared by adjusting the calcined calcium concentration to be 0.01 wt% to 1 wt%.