JPS61205202A - Nematocide and nematocidal method - Google Patents

Abstract

PURPOSE:A nematocidal agent which is composed of a culture mixture containing spores of Bacillus sphaericus T-1 is obtained and used to control nematodes causing injury by continuous cultivation of vegetables or pine blight. CONSTITUTION:The objective nematocide contains a culture product resulting from cultivation of Bacillus sphaericus T-1 (FERM-7820) in a liquid medium such as broth. The culture product means the culture mixture itself, its concentrate or dried product and may contain cell bodies or filter them off. The resultant nematocide is brought into contact with soil nematodes or Bursaphelenchus lignicolus by spraying to avoid injury of continuous cropping or pine blight.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a nematicidal material and a nematicidal method effective against continuous cropping disorders and pine wilt damage in vegetables.

(Conventional technology and its issues) Today, continuous cropping problems in vegetables are widespread and causing great damage. This is mainly due to the large number of soil nematodes. Conventional countermeasures have been to disinfect using nematocides such as methyl bromide and chloropicrin, or to use E.
DB agents and DB CP agents are used, but these chemicals are toxic and their use is a big problem because they cause environmental pollution and adverse effects on humans and livestock. Pine blight is also thought to be caused by a nematode called the pine nematode carried by the pine beetle that infiltrates pine trees, and the countermeasure against this disease is the spraying of so-called organic phosphorus agents, which are very problematic, although they are of low toxicity. is being carried out. However, it cannot be considered that the effect is sufficient.

As a result of intensive research to solve these problems related to nematodes, the present inventor discovered Bacillus sphaericus (13
acillus aphaericus) T-1
(FERM P-7820, FERM P-7820
) (7) The present inventors have discovered that soil nematodes or pine nematodes can be killed by spraying and contacting the culture solution with these nematodes, thereby achieving the present invention.

The nematicidal active ingredient contained in the above culture solution is heat resistant, so the culture solution can be used as is or after removing bacterial cells by filtration, heated, concentrated under normal pressure or reduced pressure, and dried. It is effective against nematodes even if it is powdered and sprayed, it can kill nematodes.

(Structure of the Invention) The gist of the first invention is “Bacillus sphaericus”
A nematicidal material consisting of a spore-containing culture of Bacillus sphaericus T-1 bacterium," and the gist of the second invention is
1ussphaericus) nematicidal method using a spore-containing culture of the T-1 bacterium.

The Bacillus sphaericus T-1 bacterium used in the present invention is listed in Microbial Technology Research Institute, Microbiological Research Institute, Microbiological Research Institute No. 7820.

The "culture" of the present invention is Bacillus sphaericus T-1
It refers to the culture solution itself obtained by culturing bacteria in a liquid medium, or its concentrate or dried product, and the above-mentioned culture solution refers to both the culture solution containing the bacteria and the culture solution from which the bacteria have been removed by filtration etc. The above-mentioned liquid medium is not particularly limited as long as it is a liquid medium in which bacteria of the genus Bacillus normally grow, but ordinary broth, tryptone broth, etc. are suitable.

Next, examples of the present invention will be described to specifically explain the present invention and its effects.

Examples 1 to 2 Bacillus sphaericus T-1 was cultured on an ordinary agar medium to obtain a stock strain, and from this slant culture, one platinum loop was inoculated in 10 mL of ordinary buoy-1y (pH 7,2), and 35
After incubation at ℃ for 48 hours, the same ordinary broth 20
0m/' and cultured under the same conditions for 48 hours, and this culture solution was further transferred to 4000ml of the same ordinary broth as above.
Aerated culture was performed at 5°C for 48 hours in a small jar funimentor. As a result, a culture solution with a bacterial numerical IQ/ml was obtained. This culture solution is one of the embodiments of the first invention (Example 1), but the powder obtained by heating this culture solution to about 100°C and drying is also an embodiment of the first invention (Example 1). 2), which is a nematicidal material having nematicidal ability.

Example 3 The root knots attached to the roots of eggplant are collected and crushed by adding a small amount of sterilized water. This liquid was examined under a microscope at a culture ratio of 60 times.
The nematodes included are Nekopus nematodes (Meloid)
gyne spp,), sucked up five of them with water and dropped them onto the center of a sterilized petri dish, added one drop of the culture solution from Example 1 (bacterial count: 1010/rnl), and left to stand still at 25°C. (experimental area).

As a control, 5 nematodes were sucked up together with water from the above-mentioned root knot slip solution and dropped onto another sterilized petri dish (control group). As a result of observing the movements of the nematodes in both petri dishes at 5-minute intervals, it was found that 30 minutes after the drop of the culture solution, all 5 nematodes in the test area stopped moving and swallowed the contents through their mouths. was observed vomiting, and it was confirmed that the patient was clearly dead. On the other hand, in the control group, the animals continued to move even 30 minutes after being collected in a petri dish, and movement was observed even 24 hours later, confirming that they were alive.

Example 4 Potato cyst nematode (Heteroderas
pp,) K was tested in the same manner as in Example 3.
However, the dry powder of Shibacillus sphaericus (Example 2) was used instead of the culture solution.) As a result of observation, all five nematodes in the test area died within 30 to 40 minutes, but in the control area, all five nematodes lived for a long time. It was observed that

Example 5 A hole was made in the trunk of a dead pine tree suffering from stock blight, and the resulting pine wood powder was collected.The powder was ground as finely as possible, and then suspended in sterilized water. was filtered through gauze. In this P solution, 5 P. nematodes were placed on a sterilized Petri dish along with a small amount of F solution, and the culture solution of Example 1 was filtered to remove the bacterial cells in the same way as in Example 3. One drop was added and observation was continued using a speculum in the same manner as in Example 3. As a result, all five worms stopped moving 40 minutes after the addition of the culture solution. Although this nematode was transferred to another petri dish and sterilized water was repeatedly added, the nematode's movement did not recover and it was confirmed that it had died.

In the control group, 24 hours after adding one drop of sterilized water instead of the culture solution, movement of all five nematodes was observed, confirming their survival.

In actual fields, for example, to prevent continuous cropping failure of eggplant, the nematocidal material of the present invention (spore-containing culture of T-1 bacteria) is diluted with water and sprayed on the field before seedlings are planted. Good to plant. In addition, to prevent stock blight, before the pine tree is affected by the disease, make several holes at the base of the pine tree and inject the nematocidal material of the present invention diluted with water using an appropriate method. It is effective to spray the above diluted solution over the entire pine tree in parallel with such injection.

Furthermore, when the nematocidal material of the present invention (spore-containing culture of T-1 bacterium) was sprayed on a field of yamatoo potatoes, it was effective in preventing the occurrence of leaf mites on the leaves of yamatoo potatoes.

Agent: Patent Attorney Masao Hori Procedure correction sergeant (voluntary) March 1985 Home Day

Claims (1)

[Claims] 1. Bacillus sphaericus (Bacillus sph)
A nematocidal material consisting of a spore-containing culture of T-1 bacteria. 2 Bacillus sphaericus (Bacillus sph)
A method for killing nematodes by bringing a spore-containing culture of the T-1 bacterium (C. aericus) into contact with nematodes.