JPS63404B2 - - Google Patents

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, problems with continuous cropping of vegetables are widespread and causing great damage. This is mainly due to the large number of soil nematodes. Traditionally, as a countermeasure,
Disinfection using nematocidal materials such as methyl bromide and chlorpicrin, or EDB and DBCP agents are used, but all of these chemicals are toxic and their use poses a risk to environmental pollution and human stockpiling. It has become a big problem because it has negative effects. It is also believed that pine blight is caused by the invasion of pine trees by a nematode called the pine nematode carried by the pine beetle, and the best countermeasures against this disease include the use of so-called organophosphorus agents, which are extremely problematic, although they are of low toxicity. Spreading is taking place. However, it is highly unlikely that the effect will be sufficient.

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

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 when powdered and sprayed, and can kill nematodes.

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

Bacillus sphaericus T- used in the present invention
1 bacterium was sent to the Microbial Technology Research Institute No. 7820.
(FERM P-7820), and its mycological properties are based on the patent application filed in 1983 by the same applicant as the present application.
-Described in the specification of No. 200182.

The "culture" of the present invention refers to the culture solution itself obtained by culturing Bacillus sphaericus T-1 bacteria in a liquid medium, or its concentrate or dried product, and the above-mentioned culture solution refers to a culture solution containing bacterial cells and This refers to both the culture solution and the culture solution from which it has been removed.

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, trypto-soy 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 a loopful of this slant culture was inoculated into 10 ml of ordinary broth (PH7.2).
After culturing at 35°C for 48 hours, transfer to 200 ml of the same ordinary broth as above and culture for 48 hours under the same conditions. Transfer this culture solution to 4000 ml of the same ordinary broth as above and place in a small jar fermenter at 35°C for 48 hours. Aerated culture was performed. As a result, a culture solution containing approximately 10 ¹⁰ bacteria/ml was obtained. This culture solution is one of the embodiments of the first invention (Example 1).
The powder obtained by heating and drying at .degree. C. is also an example (Example 2) of the first invention, and is a nematicidal material having nematicidal ability.

Example 3 Collect the root knots attached to the roots of eggplant, add a very small amount of sterilized water, and grind them. This solution was examined under a microscope at a culture ratio of 60 times to confirm that the nematodes contained therein were Meloidogyne spp., and 5 of them were sucked up with water and placed in the center of a sterile shell. , to which the culture solution of Example 1 (the number of bacteria
10 ¹⁰ /ml) was added and left to stand at 25°C (test group).
As a control, five nematodes were sucked up together with water from the above-mentioned ground gall solution and dropped into another sterilized shear dish (control group). As a result of observing the movement of the nematode in both sieves at 5-minute intervals, it was found that 30 minutes after the drop of the culture solution, all 5 of the nematode in the test area stopped moving and came out of their mouths. Contents were observed to be vomited, clearly indicating death. On the other hand, in the control group, the animals continued to move even 30 minutes after they were collected by the shearer, and movement was observed even 24 hours later, confirming that they were still alive.

Example 4 Heterodera
spp.) was conducted in the same manner as in Example 3 (however, the dry powder of Bacillus sphaericus in Example 2 was used instead of the culture solution), and the results were as follows. ~40
However, in the control area, all five animals were observed to survive for a long time.

Example 5 A hole was made in the trunk of a dead pine tree affected by pine blight, and the resulting pine wood powder was collected.The powder was ground as finely as possible, and then suspended in sterilized water. was covered with gauze. Bursaphelenchus (Bursaphelenchus) is added to this liquid.
After confirming the presence of C. lignicolus with a speculum, five pine-nosed nematodes were placed on a sterilized shear plate along with a small amount of liquid, and the culture medium of Example 1 was passed through it in the same manner as in Example 3. One drop of the solution from which the bacterial cells had been removed was added and observation was continued using a speculum in the same manner as in Example 3. As a result, all five nematodes stopped moving 40 minutes after the addition of the culture solution. Although this nematode was transferred to another tray and sterilized water was repeatedly added to it, the nematode's movement did not recover and it was confirmed that the nematode had died.
In the control group, one drop of sterilized water was added instead of the culture solution.
Even after 24 hours had passed, movement of all five nematodes was observed, confirming their survival.

In addition, in actual fields, for example, in order to prevent continuous cropping failure of eggplant, the nematicidal material of the present invention (T-1
It is best to dilute a spore-containing culture of the fungus with water and spray it on the field before planting the seedlings. In addition, to prevent pine blight, before the pine tree is infected with 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 yam, it was effective in preventing the occurrence of leaf mites on the leaves of yam.

Claims (1)

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