JPH01165506A - Microorganism for controlling disease injury of solanaceous plant and method for controlling disease injury - Google Patents

Abstract

PURPOSE:To control disease injuries of solanaceous plants with safety for humans and animals without killing microorganisms beneficially acting on production of crops and a fear of phytotoxicity and pollution, by treating plant roots, etc., with a novel microorganism Fusarium oxysporum as an active ingredient. CONSTITUTION:A novel microorganism Fusarium oxysporum MT-5009 (FERM P-9733) which is a novel strain of the species Fusarium.oxysporum obtained by separating from the rhizosphere of eggplant grown in natural farmland soil is cultivated in a liquid culture medium for molds, such as Czapek liquid culture medium, by a shaking or stationary culture method, etc., to treat plant roots or soil and control disease injuries which are hard to control of solanaceous plants, especially soil borne diseases without a fear of replant failure. Fusarium oxysporum f. sp. melongenae, Verticillium dahliae and Pseudomonas solanacearum E.F. Smith of eggplant, Meloidogne spp. of tomato, Phytophthora infestans and Pseudomonas solanacearum E.F. Smith of potato, Phytophthora capsici Leonian of green pepper, etc., are cited as main disease injuries of the above-mentioned solanaceous plants.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to microorganisms effective for controlling diseases of crops of the Solanaceae family, particularly soil-borne diseases, and a method for controlling these diseases characterized by applying the microorganisms. .

[Conventional technology]

Major diseases of solanaceous crops include eggplant half blight, eggplant half wilt, eggplant bacterial wilt, tomato late blight, tomato wilt, tomato half wilt, tomato bacterial wilt, tomato club root nematode disease, and potato late blight. , potato bacterial wilt, green pepper late blight, etc. Among these, lifestyle diseases, half-wilt, bacterial wilt, wilt, and root-knot nematode are soil-borne diseases that are difficult to control. .

Disease control methods for Solanaceous crops include spraying a fungicide on the stems and leaves to prevent airborne diseases such as late blight, but disinfectants are effective against soil-borne diseases such as hemi-wilt. In addition to soil disinfection using fumigants and steam, the use of resistant varieties or rootstocks and crop rotation are being implemented. However, chemically synthesized pesticides are often used to control soil-borne diseases because they are economically viable to a certain extent, as they pose the risk of the emergence of drug-resistant bacteria, drug damage, and pollution. Fumigants such as chloropicrin and methyl bromide indiscriminately kill microorganisms living in the soil, and they also kill microorganisms that are beneficial to crop production.Furthermore, they pose a danger to crops, humans, and livestock. On the other hand, control using resistant varieties or scripts has a problem in that the parasitic nature of the pathogen differentiates and the emergence of a pathogen race that can attack resistant plants, and there are limits to its use. In addition, in recent vegetable cultivation, due to the spread of facilities and the designation of production areas, there is a tendency for only one crop to be grown, making it difficult to implement crop rotation, and the problem of continuous cropping failure is becoming more serious.
There is.

[Problem that the invention seeks to solve]

The present invention solves the above-mentioned disadvantages in the conventional disease control of crops of the Solanaceae family, and provides a new control material that can replace synthetic pesticides, especially soil fumigants.

Means for Solving Problem c] The present inventors have developed a method of “cross-protection (cross-protection)”.
A mutual phenomenon between plants and microorganisms called cross-protection)
Baker, K. F. et al. (1974)
；Biological control of plants
Patogens Double Yu, Ecchi, Freeman, San Francisco (Biological Control
of Plant PathogensH,H,Fr
eeman, San Fran-cis IIco)
), with the aim of controlling difficult-to-control soil-borne diseases by imparting disease resistance to crops themselves.
As a result of pure isolation of many microorganisms from the natural world and conducting research with eggplants as the main target, we discovered a microorganism that is effective against diseases not only in eggplants but also in a wide range of crops in the Solanaceae family, and is safe for humans, animals, and crops, and has completed the present invention. I ended up doing it.

That is, the present invention provides a novel microorganism, Fusarium oxysporum, which is effective for controlling diseases of solanaceous crops.
um oxysporum) MT-5009 (Feikoken Bacterium No. 9733) and the new non-pathogenic microorganism are applied to plant roots or soil.

The microorganism according to the present invention is a novel strain of the Fusarium oxysporum species obtained by isolation from the rhizosphere of eggplant grown in natural field soil.

Fusarium oxysporum spp.
According to the National Institute of Health's Pathogen Safety Management Regulations, y-sporum) has the lowest level of risk. Safety for humans and animals is guaranteed, and this strain is also the same.

The microorganism according to the present invention can be easily cultured by shaking culture or static culture using a liquid medium for filamentous fungi such as a Czapek liquid medium or a potato dextrose liquid medium. Culture using a medium is also effective. It is also possible to culture in large quantities by culture using jarfamenta or soil bran culture.

The treatment method according to the present invention is applied to the roots or cultivation of crops.

The treatment is carried out on soil, and the form of treatment is effective not only for spores but also for mycelium including hyphae, as well as the culture filtrate and spore germination solution of the microorganism according to the present invention.

The roots are treated by immersing the roots in a spore or mycelium suspension, culture filtrate, or spore germination solution, and the soil is treated by irrigation or row application. It is desirable to treat at both the start of seedling raising and at the time of planting, and additional application during the cultivation period is effective in sustaining the control effect.

In addition, in the case of seed soaking treatment, the number of spores per ml of suspension is 104.
It is desirable for the effect to be at least 103, preferably at least 10'', and in the case of soil treatment, at least 103, preferably at least 10', per gram of dry matter.

In addition, by using the pest control method according to the present invention in combination with other pest control methods such as the use of resistant varieties, it becomes effective even in soils where disease-prone diseases occur, such as in continuous crop fields, where the density of pathogenic bacteria is high.

[Effect] The microorganisms and disease control method according to the present invention are extremely effective in controlling common diseases, hemi-wilt, bacterial wilt, etc. in the case of eggplants.
In the case of tomatoes, it can also be used to control soil-borne diseases such as wilt, root rot wilt, half-wilt, bacterial wilt, root-knot nematode disease, and complex diseases, as well as air-borne diseases such as late blight and leaf mold. It is valid. The same applies to other Solanaceae crops such as potatoes, green peppers, and tobacco, and is effective against similar diseases.

[Example] Hereinafter, the novel microorganism according to the present invention and the disease control method using the same will be explained in detail by giving examples.

The microorganism according to the present invention is a novel strain of Fusarium oxysporua+ obtained by isolation from the rhizosphere of eggplant grown in natural field soil, and is identified as follows.

■ It is a Fusarium genus fungus, and is identified as Oxsuborum species because it forms small conidia in a pseudocephalic shape on short basidiospores in a filamentous concave medium such as Czapek's agar medium.

■ Not pathogenic to nightshade crops such as eggplants and other crops.

■ As shown in Figure 1, the isozyme pattern of soluble esterase within the fungus is clearly different from that of pathogenic bacteria of the same genus and species of Solanaceae crops.

The isozyme pattern of intracellular esterase is
It is analyzed in the following way.

After freezing the mycelium obtained by statically culturing at 27°C for 10 days in a modified Czapek-Dox liquid medium, 0.05M
) The mixture was ground with Lis-HCl buffer, centrifuged at 10,000G, and the supernatant was used as a test sample. The test sample had a protein amount of 600 μg, and was prepared using a polyacrylamide gel for pH 9.4 (separation gel; 7.5χ; concentration gel; 2.
5χ) at a constant current of 2.5 mA.

Enzyme staining was performed by Berry and Frank.
nd Frank's method [Berry, J., A., et al.
Berry, J. A. et al.), American Journal of Botany (A. J. Bot.
Esterase staining was carried out according to , ), Regulations, 976-986 (1973) ).

Example 1 Ten eggplant seedlings (variety: Senryo No. 2) with 3rd to 4th leaf stage grown in vermiculite were used in each experimental plot. The roots of eggplant seedlings were added to a suspension of the microorganism according to the present invention, which was obtained by culturing spores in a potato dextrose liquid medium at 27°C for 6 days with shaking and diluting them with sterile distilled water to 107 spores/ml. After soaking for 30 minutes, each was temporarily planted on vermiculite. As a control, sterile distilled water was treated in the same manner and then temporarily planted on vermiculite. After 36 hours, a bacterial pathogen (Fusariu+s oxysporu+w) prepared using the same method was added.
f, sp.

melongenae)), hemi-wilt fungus (Verticilliu s
dahliae) )) each spore suspension 10'/
Soak again in 10,100O m of seedling bed soil for 30 minutes.
They were each planted and cultivated. The disease onset state was observed after 30 days, and the degree of disease onset was expressed as a class value for each leaf position on the tree.

0: No disease 1: Partially affected leaves (diminution, wilting) 2: Symptoms of about 1×2 leaves 3: Most of the leaves are infected or fallen, and the disease index for each individual is calculated using the following formula, and the average disease index is determined. I asked for Furthermore, the control rate by infiltrating this strain was calculated with respect to the average disease index of the control plot using the following formula.

Half blight Disease onset index Control rate (χ) Attack index Control rate (χ) Treatment area 9.91 1189 Control area 100 100 - The results are shown in Table 1. The spore suspension of the microorganism according to the present invention By applying this to the roots of eggplant, the incidence index of the common disease, hemi-wilt, was significantly reduced compared to the control plot, and an extremely high control effect was observed.

Example 2 A nursery bed of ±10 (lal
Eggplant seeds (variety: Senryo 2) were sown and raised, and 10 individuals were used in each experimental plot. As a control, seedlings were grown in the same manner using sterile nursery soil. After each tree was planted in 100011 on a nursery bed at the 4th to 5th leaf stage, a plant with a common disease (Fusarium oxyspormuef sp.
Sarium oxy-sporua f, sp, a
+ elongenae )), Verticillium dahlias (Verticillium dahlias)
10a+1 of each spore suspension of S. dahliae)) was inoculated by irrigation into each plant base and cultivated. After 50 days, the disease onset state was observed, the average disease index was determined in the same manner as in Example 1, and the control rate of the treated plots relative to the control plots was calculated.

Half blight Half wilt attack index Control rate (χ) Incidence index Control rate (χ) Treatment area 20 80 18 81 Control area 1
00 95 - The results are shown in Table 2. Eggplant seedlings grown in seedling bed soil containing the microorganisms of the present invention had significantly reduced attack indices for lifestyle diseases and half-wilt disease compared to the control plot. , a high pesticidal effect was observed.

Example 3 Ten eggplant seedlings (variety: Senryo No. 2) at the third to fourth leaf stage grown in vermiculite were used in each experimental plot.

The culture filtrate of the microorganism according to the present invention obtained by shaking culture at 27°C for 6 days in a Czapek liquid medium and then filtering without concave or the spores of the microorganism according to the present invention was
07 cells/ml at 27°C.
The spores were germinated by shaking culture for 2 hours, and then immersed in a spore germination solution obtained by sterile filtration for 30 minutes, and then temporarily planted on vermiculite. As a control, sterile distilled water was treated in the same manner and then temporarily planted on vermiculite. After 36 hours, the bacterial wilt (Fusarium oxysporum F.
Fusarium oxys
Porum f, sp, melongenae) spore suspension for 30 minutes again, and the seedling bed
1, each was planted and cultivated. After 20 days, the disease onset state was observed, the average disease index was determined in the same manner as in Example 1, and the control rate of the treated plots relative to the control plots was calculated.

Culture filtrate Spore germination solution treated group 32 68 15 85 Control group 100 100 - The results are shown in Table 3. By treating the roots of eggplant with the culture filtrate and spore germination solution of the microorganism according to the present invention, the control group 100 100 The disease index decreased compared to the control plot, and a high control rate was obtained.

Example 4 Ten tomato seedlings (cultivar: Ponderosa) grown in vermiculite and at the third to fourth leaf stage were used in each experimental plot. After being immersed in a spore suspension of the microorganism according to the present invention obtained in the same manner as in Example 1 for 30 minutes, each sample was temporarily planted on vermiculite.

As a control, sterile distilled water was treated in the same manner and then temporarily planted on vermiculite. After 36 hours, the wilt fungus (Fusarium
Fusarium oxy-sporum f,
sp, 1ycopersici race) J
-1), Hemi-wilt W (Verticilliua+ dahliae)
) in each spore suspension for 30 minutes, and then the seedling bed soil 1
They were each planted and cultivated at 0100O.

After 30 days, the disease onset state was observed, the average disease index was determined in the same manner as in Example 1, and the control rate of the treated plots relative to the control plots was calculated.

Wilt disease Half body wilt disease incidence index Control rate (χ) Disease index Control rate (X) Treatment area 15 85 17 81 Control area 1
00 - 90 - The results are shown in Table 4. By treating tomato roots with the spore suspension of the microorganism according to the present invention, the attack index of wilt and half-wilt was significantly reduced compared to the control plot. However, an extremely high control rate was obtained.

Example 5 Tomato seeds (variety Den Ponderosa) were sown and raised in 100 ml of nursery soil containing microorganisms according to the present invention prepared in the same manner as in Example 2, and 10 individuals were used in each experimental plot. As a control, seedlings grown in the same manner in sterile nursery soil were used. 100 on the nursery bed when the tree leaves are in the 4th to 5th leaf stage
After planting each on 0+++1, wilt disease W (Fusarium oxysvorum F.S. lycopersici race) prepared in the same manner as in Example 1
um oxysporura f.

sp, 1ycopersici race) J-
1), Hemi-wilt disease (Berticillium dahliae (
10 ml of each spore suspension of V. verticillium dbhliae) was inoculated by irrigation into each plant base and cultivated.

After 50 days, the disease onset state was observed, the average disease index was determined in the same manner as in Example 1, and the control rate of the treated plots relative to the control plots was calculated.

Wilt disease Half body wilt disease incidence index Control rate (χ) Disease index Control rate (χ) Treatment area 16 84 20 77 Control area 1
00 88 - As shown in Table 5, tomato seedlings grown on seedbeds containing the microorganisms of the present invention had significantly lower and higher disease indexes for wilt and half-wilt than in the control plot. The pesticidal effect was observed.

Example 6 Eggplant seeds (variety: Senryo No. 2) were placed in a nursery bed of ±500 m1 containing microorganisms according to the present invention prepared in the same manner as in Example 2.
were sown and raised, and 5 individuals were used in each experimental plot. As a control, seedlings were grown in the same manner using sterile nursery soil. The trees were planted at the 7th to 8th leaf stage in fields where vital diseases were most prevalent. At this time, 1/10 of the cultivation soil was added to the seedling bed soil containing the microorganism according to the present invention prepared in the same manner.

In addition, soil that had undergone sterilization (20ffi/1 (LK-)) with a chloropicrin fumigant was also used to test the soil that was severely susceptible to wilt.

After 60 days, the disease onset state was observed, the average disease index was determined in the same manner as in Example 1, and the control rate of the treated plots relative to the control plots was calculated.

Disease index Control rate (χ) Disease index Control rate (χ) Treatment area 11 89 18 82 control area
100 100 - As shown in Table 6, by treating the microorganisms according to the present invention at the time of seedling raising and planting, a control effect equal to or higher than that of chloropicrin fumigant was obtained.

Example 7 Experiments were conducted on seedlings of eggplant (variety: Senryo 2), tomato (variety: Ponderosa), cucumber (variety: Shimochifujiho), strawberry (variety: Suebumi Wase), and radish (variety: Wakakoma) Five individuals per ward were tested. They were immersed for 30 minutes in a spore suspension of the microorganism according to the present invention prepared in the same manner as in Example 1, and then planted and cultivated in 1000+ al of nursery bed soil. In addition, as a control, an eggplant pathogenic fungus (Fusariium oxysbormuef sp.
moxy-sporum f, sp, melong
enae ) ) , ) Fusarium wilt ( Fusarium
Fusarium oxyspo-ruar,
sp, 1ycopersici race) J
-1), cucumber vine splitting fungus (Fusarium oxysborumef sp. cucumerinum)
riumoxysporum f, sp, cucum
erinu+*) ), Strawberry yellowing disease fungus (Fusarium oxysporum FSP fragariae)
FusariuIIoxysporum f.

sp.
f, sp, raphani) spores? A suspension was treated and cultivated in the same manner. After 30 days, the disease state was observed and judged based on external disease symptoms such as growth inhibition, leaf thinning, and wilting.

Table 7 Pathogenicity of eggplant to major crops by the microorganism of the present invention
Tomato cucumber Strawberry radish pathogen +++ 10+
+ 10+ +++ 10++*+++; Withering or on the verge of withering ++; Disease symptoms are severely observed +: Disease symptoms are slightly observed -; No disease symptoms are observed at all. As shown in Table 7, the results indicate that the present invention The microorganisms involved did not show any pathogenicity to solanaceous crops such as eggplant and tomato, as well as major crops such as cucumber, strawberry, and radish.

〔Effect of the invention〕

The novel microorganisms and disease control method according to the present invention are safe for humans and livestock, there is no fear of chemical damage or pollution, there is no killing of microorganisms that are beneficial to crop production, and there is no fear of continuous cropping damage. It is effective in controlling difficult-to-control diseases of solanaceous crops, and is useful for agricultural production.

[Brief explanation of the drawing]

FIG. 1 shows the microorganism Fusarium oxysporum (FusariuIIloxysporum sp) according to the present invention.
) and eggplant pathogens (Fusarium oxysporumef sp. melongena s, (Fusariu
moxy-sporue+ f, sp, lle
longenae)), tomato wilt fungus (Fusarium oxyspo-rum
l sp, 1ycopersici race)
It is an isozyme pattern of intracellular soluble esterase of J-1).

Claims (2)

[Claims] (1) A new microorganism, Fusarium oxysporum, that is effective in controlling diseases of solanaceous crops.
orum) MT-5009 (Feikoken Bibori No. 9733) (2) New non-pathogenic microorganism Fusarium oxysporum (Fusarium oxysporum) MT-
A method for controlling solanaceous crop diseases, characterized by applying 5009 (KAIKEN BIKIYO NO. 9733) to plant roots or soil.