JP2642756B2 - Control of turfgrass disease and greening soil improvement material - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a turfgrass disease controlling and green-retaining soil improving material, in particular, it can control turfgrass disease without using pesticides, and keeps turfgrass green for a long time. The present invention relates to a soil-improving material that is harmless and does not pollute the natural environment. The soil-improving material of the present invention is particularly useful for managing a large lawn such as a golf course.

[Conventional technology]

Means of controlling turfgrass disease that can be incorporated into the daily maintenance of golf courses include cultivated pest control and pesticide (fungicide) control. Currently, most golf courses are controlled by pesticides.

[Problems to be solved by the invention]

At a golf course, turfgrass is frequently cut off and stepped on with shoes, so it is more susceptible to disease than turfgrass in other places, and the lawn is required to be beautiful. It is in. For example, greens are generally sprayed with pesticides 15 to 22 times a year, which has caused natural destruction and water pollution by pesticides far beyond expectations.In recent years, there have been campaigns against golf course construction and environmental protection. ing.

In addition, prefectures have issued “Guidelines for Safe Use of Pesticides for Golf Courses” to golf courses, and guidance on the use of pesticides has begun, and it is expected that regulations on the use of pesticides will become increasingly strict in the future.

Accordingly, an object of the present invention is to provide a harmless soil-improving material that can control turfgrass disease without using pesticides and can keep turfgrass green for a long time without polluting the natural environment.

[Means for solving the problem]

The present inventor has been conducting research on microbial control of soil diseases and research on the effects of fertilizers on microorganisms for many years.As a result, Trichoderma shows high antagonism to Rhizoctonia, the main pathogen of turfgrass, and nitrogen. We found that some fertilizers reduced the germ pathogens.

Furthermore, based on the above findings, the present inventor has conducted various studies on cultivated pest control means for turfgrass disease. It has been found that a soil conditioner that achieves the above object can be obtained by combining a pesticide-resistant Trichoderma bacterium that is antagonistic to certain rhizoctonia, picium, fusarium, and the like.

The present invention has been made based on the above findings, and screens for Trichoderma having high antagonisticity against Rhizoctonia, then suspends the Trichoderma in an ethyl methanesulfonate solution and cultures the Trichoderma to obtain Trichoderma. After screening the mutant strain and then selecting a strain from the mutant strain that has not lost antagonism to Rhizoctonia bacterium, the strain was screened for pesticide-resistant Trichoderma according to the concentration gradient plate method of Cyvalsky et al. ,
It is intended to provide a turfgrass disease control and green-retaining soil improving material, characterized in that the pesticide-resistant Trichoderma is contained in a base material.

Hereinafter, the turfgrass disease controlling and green retaining soil improving material of the present invention will be described in detail.

The pesticide-resistant Trichoderma bacterium used in the present invention is obtained, for example, as follows.

First, a trichoderma that is highly antagonistic to Rhizoctonia is screened, and then Ethylmethanesulfonate, a substance that induces a high rate of mutation in eukaryotic microorganisms from the Trichoderma.
A mutant strain of Trichoderma is screened using (EMS) according to the method described in the Microbiology Experiment Method (edited by the Microbial Research Method Roundtable, published by Kodansha, page 293). Next, a strain that has not lost its antagonistic ability against Rhizoctonia is selected from the mutants, and a mutant resistant to the pesticides daconil and thiuram, which are most frequently used for controlling lawn brown patches (pathogenic bacteria: Rhizoctonia), is selected. Separation method of Szybalski [V. Bryson and W. Sz
ybalski., Science 116, 45 (1952)] to obtain pesticide resistant mutants. Next, the antagonistic power of this pesticide-resistant mutant against Rhizoctonia is again checked, and a strain having a high antagonistic power is selected to obtain the pesticide-resistant Trichoderma used in the present invention.

The purpose of preparing the pesticide-resistant mutant strain is to prevent the antagonistic antibacterial used in the present invention from being killed even when the pesticide is sprayed because an excessive pesticide is sprayed on the golf course as described above.

The above pesticide-resistant Trichoderma may be not only viable fungi, but also concentrated, spray-dried, freeze-dried, freeze-thawed and the like. In addition, culture of the above pesticide-resistant Trichoderma is, of course, liquid culture,
Solid cultivation may be used.

The content of the pesticide-resistant Trichoderma is 100
The amount is preferably 0.1 part by weight or more with respect to part by weight, and there is no particular upper limit.

Examples of the substrate used in the present invention include organic fertilizers, inorganic fertilizers, and materials for enhancing the activity of turfgrass, and these may be used alone or in combination of two or more.

As the organic fertilizer and the inorganic fertilizer, nitrogen fertilizer,
It is preferred to combine a phosphate fertilizer and a potassium fertilizer.

As the nitrogen fertilizer, CDU of organic fertilizer, urea of dry blood and inorganic fertilizer are preferable since they have an effect of reducing soil pathogenic Fusarium bacterium, and when these three are mixed, the growth of turfgrass is very good due to a synergistic effect. Become. The mixing ratio of the above three is preferably CDU6, dry blood 5, and urea 4 (weight ratio), but is not particularly limited.

The mixing amount of the nitrogen fertilizer is preferably such that the nitrogen component content is 4 to 10% by weight in the soil conditioner of the present invention.

Further, as the above-mentioned phosphate fertilizer, lime perphosphate is preferred for the reasons described below, but any fermentation bacteria capable of decomposing cellulose and hemicellulose may be used. Examples of such a phosphate fertilizer include heavy superphosphate. Lime, magnesia superphosphate,
For example, molten phosphoric acid, hard-burned heavy phosphorus, and the like. Also, salts such as monopotassium phosphate and dipotassium phosphate may be used. Since turf grass on a golf course is frequently mown, after mowing, a residue of turf grass, so-called thatch, remains and becomes a home for pathogenic bacteria of the turf grass, causing disease. Superphosphate lime has the effect of increasing the decomposition of cellulose and hemicellulose and not denitrifying bacteria, thereby accelerating the decomposition of thatch.

The mixing amount of the phosphate fertilizer is preferably such that the content of the phosphoric acid component is 2 to 8% by weight in the soil conditioner of the present invention.

Examples of the potash fertilizer include potash fertilizers used for general agriculture, for example, potash chloride, potash sulfate, potash sulfate, potassium silicate, and the like.

The mixing amount of the potash fertilizer is preferably such that the potash component content is 1 to 5% by weight in the soil improving material of the present invention.

As the material for enhancing the activity of the turfgrass, zeolite having a high base substitution capacity for enhancing fertilizer retention and improving soil physical properties, and oyster shells having rooting promoting effect are preferable.
In addition to the above, examples of those having a high base substitution capacity include, for example,
Humic acid, perlite, vermiculite and the like can be mentioned, and those having an effect of promoting rooting include fossils of shellfish and coral in addition to oyster shells, and these may be used.

The mixing amount of the material for enhancing the activity of the turfgrass is preferably 25 to 35% by weight in the soil conditioner of the present invention.

The soil conditioner of the present invention is obtained by, for example, mixing and adsorbing the pesticide-resistant Trichoderma on the substrate.

Soil improvement material of the present invention can be used in the same manner as pesticides and fertilizers normal for turfgrass, the amount used varies depending on the turfgrass kind usually lawn 1 m ² per 50 to 200
It may be about g.

〔Example〕

Next, the present invention will be described based on the following examples, but the present invention is not limited by these examples.

Example 1 9.2 ml of a 0.2 M phosphate buffer (pH 8.0) was placed in a large test tube, and 0.5 ml of a 4.0% glucose solution and 0.3 ml of a stock solution of ethyl methanesulfonate (EMS) were added to obtain an EMS solution.

On the other hand, in advance in the potato decoction medium in the Petri dish
Trichoderma bacterium, which has an antagonistic effect against Rhizoctonia bacterium, cultured at 28 ° C. for 4 days, is treated with the EMS per petri dish.
Pour 10 ml of the solution and drop the spores with a brush to make a spore suspension. Transfer this spore suspension to a 25 ml Erlenmeyer flask,
Keep at 30 ° C with gentle shaking. After 1, 2, 4, 6 and 8 hours, take 0.2 ml of the spore suspension, add it to 98 ml of 6% sodium bisulfite solution, leave for 10 minutes,
Is poured into a petri dish, and then a nutrient medium is poured. Alternatively, 1 ml of the above spore suspension is added to a nutrient medium previously poured into a petri dish and spread with a glass rod. A colony of the mutant strain formed on the plate on the third to fourth days of culture at 28 ° C. is transplanted to a slant medium in a test tube to obtain a mutant strain of Trichoderma.

Example 2 Screening for pesticide-resistant mutants was performed by the concentration gradient plating method of Szybalski et al. [V. Bryson and W.
Szybalski., Science 116, 45 (1952)].

That is, 20 ml of nutrient medium agar is poured into a Petri dish, and the bottom end of the Petri dish is tilted just enough to be covered and hardened.Then, the Petri dish is placed horizontally, and 20 ml of nutrient agar to which an appropriate pesticide is added. 10 ⁷ to 10 ⁸ spores of Trichoderma of the mutant strain obtained in Example 1 are added and hardened.

When screened by this method, coroni grown in a high concentration region has pesticide resistance.

According to the above-mentioned method, first, a mutant strain having a resistance of 250 times to daconil was obtained, and a mutant strain having a resistance to thyunim (500 times) was further screened from the mutant strain, and a pesticide-resistant mutant was screened. Got the strain. According to the above method, mutant strains having resistance to various pesticides, not limited to the pesticides, can be obtained.

Example 3 One side of a potato decoction agar medium poured into a Petri dish was inoculated with Rhizoctonia bacterium, a pathogen of turfgrass, at 28 ° C.
For 2 days, and then, on the other side, Examples 1 and 2
A pesticide-resistant mutant strain of Trichoderma was screened by the method described above. After culturing this at 28 ° C. for 3 days, it was confirmed with a microscope that the hypha of Rhizoctonia was destroyed by the pesticide-resistant Trichoderma.

Example 4 After thoroughly mixing rice bran 1 and isolite 4, water was added to the mixture, and the mixture was stirred. About 800 ml of an enoki cultivation bottle was filled with about 500 ml, and sterilized at 1.5 atm for 30 minutes. The pesticide-resistant mutant strain of Trichoderma screened in 2 was inoculated and cultured at 28 ° C. to obtain a pesticide-resistant Trichoderma strain.

Example 5 100 ml of a nutrient liquid medium was dispensed into a 500-ml Sakaguchi flask and sterilized, and the pesticide-resistant mutant strain of Trichoderma screened in Examples 1 and 2 was inoculated, followed by shaking culture at 28 ° C. Four days later, the culture was sprayed on 400 ml of rice bran which had been dry-heat sterilized at 120 ° C. for 6 hours and further cultured at 28 ° C. for 2 weeks to obtain pesticide-resistant Trichoderma.

Example 6 Oyster shell 20 kg, zeolite 20 kg, lime superphosphate 7.8 kg, C
DU 3.6 kg, dry blood 3.0 kg, urea 2.4 kg, sulfuration 1.2 kg and pesticide-resistant Trichoderma cultivated in Example 4 or Example 5
2 kg was mixed well with a mixer to obtain a turfgrass disease controlling and green improving soil improving material of the present invention in which N: P: K was 4: 2: 1.

Example 7 Using the turfgrass disease controlling and green-retaining soil improving material of the present invention obtained in Example 6 to retain turfgrass in green (retain fertilizer effect)
The effect was investigated.

The test of green retention (fertilizer retention) effect was conducted by renting a nursery at the vent of a golf course. As a control fertilizer, green phosca (10-10-1) often used in golf courses was used.
0) and birdy turf (8-12-10). Scale of the test is a two-compartment of 10m ² of 2m × 5m.

The amount of soil improvement material of the present invention is 80 g / m ² (nitrogen component 3.
2g / m ² ), 30g / m ^{2 for} green phosca (3.2g / nitrogen component)
m ² ), birdy turf 40 g / m ² (nitrogen component 3.2 g / m ² )
Thus, the nitrogen components were made substantially the same amount.

The green retention (fertilizer retention) effect was determined on the 40th day after use by examining the growth rate, number of buds, above-ground fresh weight, dry weight and root fresh weight, dry weight, and the like. The results are shown in Table 1 below.

From the results shown in Table 1, when the soil conditioner of the present invention is used, the number of buds, the above-ground part and the root part are higher than when using the fertilizer that is often used in golf courses, as well as in the untreated area. It turns out that it has a remarkably excellent green retention (fertilizer effect retention) effect.

In addition, the superiority of leaf color and growth degree is the soil improvement material of the present invention>
Birdy Turf> Green Hoska> No application zone.

Example 8 Using the turfgrass disease controlling and green-retaining soil improving material of the present invention obtained in Example 6, the effect of retaining green (fertilizing effect) on Korai turf was examined. As a control fertilizer, bioferty (5-5-2) used in golf course greens
Was used. Scale of the test is a two-compartment of 5m ² of 2m × 2.5m.

The amounts used were 100 g / m ^{2 for} the soil conditioner of the present invention, 80 g / m ² for biofertility, and the same amount of nitrogen component as 4 g / m ² .
One month and two months after use, the green retention (fertilizer retention) effect was determined by examining the number of green remaining buds and the above-ground fresh weight and dry weight. The results are shown in Table 2 below.

 The test was performed when the Korai turf withered.

From the results shown in Table 2, it can be seen that when the soil conditioner of the present invention was used, the number of green shoots, fresh weight, dry weight, etc. were remarkably superior to those using the control fertilizer.

When the soil improving material of the present invention is used, Korai turf can be kept green even in the middle of winter.

Example 9 Using the turfgrass disease control and green-retaining soil improving material of the present invention obtained in Example 6, a disease control effect test on large patches and brown patches of turf was performed as follows.

That is, Isolite 4, rice branka 1 and water 2 were mixed, and 100 ml of a mayonnaise bottle having a diameter of 6 cm and a depth of 12.5 cm was filled and sterilized. Cultured for a week. Then, the Korai turf was cut out with a cup having a diameter of 5 cm, the pathogenic bacteria in the mayonnaise bottle were stirred, and the Korai turf was placed thereon. After 15 days in artificial weather at 25 ° C, the diseased area ratio and disease index were examined.

As control pesticides for the disease control effect test, captan, benlate and moncat were used. The amount used is 100 g / m ^{2 for} the soil conditioner of the present invention, and 500 times // m for captan.
² , Venrate was 2000 times // m ² and Moncut was 1000 times // m ² . In the above test, each test material was repeated three times.

 The disease index was calculated by the following equation.

1 = Affected area is 10% or less. 2 = Affected area is slightly less than 11-30%. 3 = Affected area is 31-50%. 4 = Affected area is 51-80%. 5 = Affected area is 81%. The results of the above test are shown in Table 3 below.

From the results shown in Table 3, when the soil improvement material of the present invention was used, the disease area ratio and disease index of the large patch and brown patch on the lawn were significantly lower than those using pesticides. It can be seen that the improved material is more effective in controlling lawn disease than pesticides.

Example 10 Using the turfgrass disease controlling and green-retaining soil improving material of the present invention obtained in Example 6, a disease controlling effect test on large patches of turf was carried out.

The disease control effect test of the large patch of lawn was carried out by renting a nursery at a golf course vent. Captan and benlate were used as control pesticides. Scale of the test is a two-compartment of 20m ² of 2m × 10m.

The amounts used were 100 g / m ^{2 for} the soil conditioner of the present invention, 500 times // m ^{2 for} captan, and 2000 times // m ^{2 for} benlate.

The effect was determined by examining the number of occurrences of the large patch, its area ratio, the number of buds, the above-ground fresh weight and the dry weight.

The numerical values shown in Table 4 below were obtained after a survey 60 days after use.

From the results shown in Table 4, when the soil conditioner of the present invention was used, the number of large patches generated and the area ratio thereof were:
It can be seen that the number of buds on the lawn, the live weight and the dry weight thereof are much lower than those in the pesticide-sprayed area.

[Effects of the Invention] According to the soil conditioner of the present invention, it is possible to control turfgrass diseases without harm and without polluting the natural environment. Since the lawn can be managed, the activity of the turfgrass can be enhanced, and the green color of the turfgrass can be maintained for a long time, various effects such as saving fertilizer and saving labor can be achieved.

Claims (2)

(57) [Claims] 1. Screening for a Trichoderma bacterium which is highly antagonistic to Rhizoctonia bacterium, then suspending the Trichoderma bacterium in an ethyl methanesulfonate solution and culturing to screen for a mutant strain of Trichoderma bacterium;
After selecting a strain that has not lost its antagonistic power against Rhizoctonia bacterium from the mutant strain, the strain is screened for pesticide-resistant Trichoderma according to the concentration gradient plate method of Cyvalsky et al., And the pesticide-resistant Trichoderma is screened. A turfgrass disease controlling and green-retaining soil improving material characterized by being contained in a base material. 2. The turfgrass disease control and green-retaining soil improvement according to claim 1, wherein the base material is selected from one or more of a group consisting of an organic fertilizer, an inorganic fertilizer, and a material for enhancing the activity of turfgrass. Wood.