JPH0246283A - Control of plant blight by microorganism - Google Patents

Abstract

PURPOSE:To effectively control plant blights such as soil blight without causing destruction of microorganism phase in soil and environmental pollution by treating plants with a bacterium belonging to the genus Pseudomonas tolaasii while being live as it is. CONSTITUTION:A live cell of bacterium such as Pseudomonas tolaasii paine 1915;814 (FERM P-10159) belonging to the genus Pseudomonas tolaasii is suspended in distilled water to give a suspension having usually 10<7>-10<10> bacterium concentration based on 1ml suspension and plant materials such as seeds subterranean stems, roots, stems or leaves are immersed in the suspension for a moment-about 18 hours.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention is directed to the use of bacteria such as Pseudomonas tolani (Pse).
The present invention relates to a method for controlling plant diseases by treating plants with live Udomonas tolaasii.

[Conventional technology]

As a method of controlling plant diseases, chemical control using agricultural and horticultural fungicides and soil fungicides is carried out, but diseases that are resistant to these fungicides are left behind as difficult-to-control diseases and are left behind without any means of control. There is. Furthermore, due to continued use of pesticides for many years, there is a risk of environmental contamination due to the destruction of normal microflora and the natural accumulation of fungicides and their metabolites.

For example, it is intended to control potato scab, cucumber vine splitting, cucumber seedling damping-off, cucumber damping-off late blight, etc., and also to effectively control above-ground diseases such as potato summer blight.

[Means to solve the problem]

The present inventors have discovered a method for controlling plant diseases by treating plants with bacteria belonging to Pseudomonas tolan. The method of the present invention will be explained in detail below.

Bacterial seeds used in the present invention Monas tolan (pse
Although udomonas spp. was isolated from a mushroom, this bacterium has been well known to the public since ancient times.

The bacteriological properties of this bacterium have already been investigated and reported in detail (Bacteriology of Artificially Cultivated Mushrooms, 1985, Ministry of Education, Culture, Sports, Science and Technology Grant-in-Aid for Scientific Research (C1 Research Results Report, 1986).
In March 2017, principal investigator Yuzen Suyama (p. 23) discovered that Pseudomonas trans, which has high plant disease control activity among these bacteria,
pain (pseudomonas t:olaasii)
p'aine) 1915; Regarding the 814 strain,
A summary of the bacterial harmful properties is as follows.

This bacterium is a motile bacillus and an aerobic bacterium with polar hairs. There was no formation of spores or capsules, and the Durham reaction was negative. It produces white, round, hill-like, smooth, translucent, viscous colonies on meat juice agar.

pseudomonas agar F
) In the culture medium, it produces milky white, opaque, flat, peripheral Rugh-type colonies. Growth on these media is fast, with colonies measuring 5 to 8 mm in size after 48 hours of culture. Growth in bouillon liquid is good, becoming turbid in 2 to 5 days and producing a large amount of precipitate, and after 7 to 10 days of culture, a fungal film is formed on the surface of the culture liquid and a ring is formed on the wall of the test tube. Growth in peptone water is almost the same as in bouillon. Growth in the Usinski clan is also good, forming a large amount of precipitate, fungal film, and rings. It also produces a yellow-green pigment. Growth is poor in the Fermi clan, making the culture solution slightly cloudy and producing a small amount of precipitate, while in the Kohn and Frenkel clans it does not grow. The culture temperature is 25 to 28°C unless otherwise specified.

Does not grow at 41°C, turns blue and digests BTB milk. Salt tolerance is 5%. Glucose is oxidatively broken down and Ki
ngs B, produces blue-green fluorescent pigment in PAF medium, or does not produce biocyanin.

PAF medium also produces a reddish-pink water-soluble pigment.

Does not accumulate β-hydroxybutyric acid granules. Catalase activity, oxidase activity, arginyl dihydrolase activity, lecithinase activity, tyrosinase activity, urease activity, and phosphatase activity are positive. tween 8
Hydrolyzes gelatin, oxidizes gluconic acid, and produces ammonia. Hydrolysis of margarine, esculin, alftin, dissolution of pectin, reduction of nitrate, hydrogen sulfide,
Indole production, MR test, V and P reactions are negative. The potato pieces do not rot and the inoculated area turns brown to black. Tobacco hypersensitivity reaction was negative.

Acid is produced using ribose, xylose, arabinose, glucose, mannose, galactose, fructose, cellobiose, melipiose, trehalose, mannitol, glycerol, sorbitol, and inositol.

Rhamnose, lactose, sucrose, melezitose, mandose, raffinose, dextrin, inulin, salicin, α-methyl glucoside, sulcitol, aesculin are available in the following range: 1° fft12 phosphoric acid, citric acid, succinic acid, fumaric acid, malic acid, acetic acid , lactic acid, and formic acid, but not tartaric acid, propionic acid, benzoic acid, hippuric acid, and butyric acid. In addition, white 1ine is formed using PAF medium.

As mentioned above, Pseudomonas tranpein 1915;
Strain 815 produces a blue-green fluorochrome in King, B and PAF media, does not produce levan, has positive oxidase activity and arginine dihydrolase activity, oxidizes gluconic acid, does not reduce nitrate, Potato pieces did not rot, the tobacco hypersensitivity reaction was negative, and no sucrose and tartaric acid were used, and white was grown in PAF medium.
It showed the characteristic of forming 1ine.

Based on these characteristics, [Purge Aids Manual
Identification Op Shedomonas Traci: The White Line Test in Agar & Preece, Volume 1 (First Edition, 1984) J. When compared with known bacterial species from literature such as Pine Shroom Tissue Block Rapid Tesla, Journal of Applied Bacteriology, 47:401-407 (1979) J, the description of Pseudomonas tolan was confirmed based on the culture properties. Based on the coincidence, Pseudomonas tranpein 1915 (Pseudomonas
stolaasii paine 1915). However, since this strain has the characteristic of having high activity in controlling plant diseases, this strain will be referred to as Seed Monas transvein 1915; 81.
4 (Pseudomonas tolaasiipa
ine1915;814). This strain was submitted to the Institute of Microbial Technology, Agency of Industrial Science and Technology as of July 29, 1985, under the microbial consignment number 1 "Feikoken Bacteria Collection No. 10".
No. 159 (FERMp-10t59) J.

A method for culturing Pseudomonas tolan is, for example, a known bouillon liquid medium (ingredients: 10 g of meat extract, 1 g of peptone).
Inoculated into 0g 1 salt 5g, distilled water 12), 25-28℃
It is sufficient to culture with shaking for 48 hours. It may also be cultured in a slant medium or plate medium containing agar.

Next, the cultured bacteria are usually treated as follows to prepare a suspension. In the case of a liquid medium, the culture is followed by centrifugation (for example, at 3000 rpm for 30 minutes), and the precipitate is suspended in distilled water. In addition, in the case of a slant culture medium or a flat plate culture medium, the bacterial bodies may be scraped off in sterilized water and suspended.

Bacterial concentrations in suspensions are typically between 10 and 1 ml of suspension.
The number is 10, preferably 10 to 10.

In order to make the bacterial cells adhere well to the plants, an adjuvant such as a spreading agent, usually 0.1 to 1%, may be added to the bacterial suspension.

Examples of the spreading agent include, but are not limited to, carboxymethyl cellulose, sodium polyacrylate, xanthan gum, and polyethylene oxide. Plants, such as seeds, rhizomes, roots, stems, leaves, etc., are immersed in the suspension prepared in this manner for a moment to 18 hours, preferably for about 10 seconds to 3 hours. This treatment is effective up to two weeks before the day of sowing or transplanting, but
Preferably, on the day of dissemination or transplantation.

Diseases targeted by the method of the present invention include soil diseases of each MMi species, such as potato scab, cucumber seedling damping-off, cucumber vine splitting disease, cucumber damping-off late blight, etc., and diseases that occur in above-ground parts. , for example, potato summer blight, etc., but are not limited to these.

〔Effect of the invention〕

The present invention has the following effects and advantages compared to conventional methods.

(1) As is clear from the Examples described below, it became possible to effectively control plant diseases by the method of the present invention, that is, by treating plants with the living bacterial seed Monas tolan.

(2) It is extremely practical because diseases that are difficult to control, such as soil diseases, can be controlled with simple treatments.

(3) Since diseases can be controlled by treating only the plants, there is no need to worry about destroying the microflora in the soil.
Moreover, there is no fear of environmental pollution.

〔Example〕

The present invention will be explained below with reference to Examples.

Example 1 A liquid medium containing 1% meat extract, 1% peptone, and 0.5% salt was added to each test tube with a diameter of 17 mm and a length of 18 cm.
Dispense 0 mt, sterilize it in an autoclave, inoculate it with one platinum loop of Pseudomonas tolan, and incubate at 25°C for 48 hours with a shaking width of 5.
cm, 80 reciprocating shakes for 1 minute, and the bacterial suspension obtained by culturing 5 times was centrifuged at 3,000 rpm for 30 minutes, and the resulting precipitated bacterial cells were added to 1A of distilled water containing 0.5% carboxymethyl cellulose. A suspension of bacteria was prepared.

Potatoes (variety Nibaron) were soaked in this for 1 hour,
Four potatoes were sown per pot in clay pots with a diameter of 30 cm in a greenhouse. One week after sowing, the potato scab disease fungus (Streptomyces) that had been cultured in advance was grown.
5 cavies) was inoculated into the soil in the pot.

2.5 months after sowing, the new soul stems were excavated and the development of potato scab was investigated.

The degree of onset of the disease is calculated using the formula shown below.
The control rate was calculated from this, and the results are shown in Table 1.

No table Treatment Ward 100 3.0 Example 2゜Potato decoction agar medium (200g potato, 1 decoction
1. Dispense 1 Qm of an agar medium prepared with 20 g of sucrose and 20 g of agar into a test tube with a diameter of 17 mm and a length of 18 cm, sterilize it in an autoclave, solidify it, and prepare a slope. Inoculate 1 platinum loop of Tran and inoculate at 25℃ for 4
After culturing for 8 hours, IQml of sterile distilled water was added, and the bacterial cells were scraped off from the surface of the slope with a platinum loop, and this was placed in 1 type of distilled water to prepare a bacterial suspension.

Potatoes (variety Nibaron) were soaked in this for 3 hours,
Four potatoes were sown per pot in clay pots with a diameter of 30 cm in a greenhouse.

After examining the number of above-ground plants per pot 4 weeks after sowing, we used the potato summer blight fungus (Al
ternaria 5olani) was spray-inoculated onto the above-ground stems and leaves. One month after inoculation, the disease status of potato summer blight was investigated. The degree of disease onset was determined by subtracting the number of plants on the day of the survey from the number of plants on the day of inoculation to calculate the number of dead plants to calculate the disease attack rate, and the results are shown in Table 2.

Untreated area 16 4 12 75.0 Example 3 One platinum loop of Shedomonas tolan was inoculated onto a slope prepared with potato decoction agar medium, and after culturing at 25°C for 72 hours,
Distilled water containing 0.2% carboxymethyl cellulose 10
m1 was added, and the bacterial cells were scraped off from the slope surface with a platinum loop to create a bacterial suspension.

Seeds of cucumber (variety: Setsunari Ochiai) were soaked in this for 3.0 seconds, and cucumber seedlings (l (hizoctonias)
olani) 3 seeds per petri dish were inoculated onto a potato decoction agar plate inoculated with bacterium blight in the center of the petri dish. Sowing 7
After a day, the formation of a growth inhibition zone of cucumber seedling blight bacteria around the cucumber seeds and the degree of onset of cucumber seedling blight were investigated, and the results are shown in Table 3.

Table-3 Inhibition zone Disease onset degree procedural aids 1986? 20th of the month

Claims (1)

[Claims] (1) A method for controlling plant diseases characterized by treating plants with bacteria belonging to Pseudomonas torashii.