JPH08193017A - Seed - Google Patents

Abstract

PURPOSE: To provide a seed treated with an N-acyllactam compound and a fluorescent bacteria and effective for controlling the blight and promoting the growth of crops to improve the productivity of the crops. CONSTITUTION: A seed is put into a mixture of an aqueous solution of an Nacyllactam compound (e.g. 1-[2-(4-hydroxyphenyl)ethanoyl]-2-piperidone) and a suspension of cells of a fluorescent bacterial strain (e.g. Pseudomonas putida IFO-3738) and treated e.g. by a seed soaking evacuation method under reduced pressure. The amount of the N-acyllactam compound is 1mg and that of the fluorescent bacteria is 10<8> cells based on 1ml of the seed. The fluorescent bacterial cells effective e.g. for promoting the growth of plant or suppressing the outbreak of plant blight caused by phytopathogenic microorganism are fixed in the stage of seed and the fixed fluorescent bacterial cells are living in the seed or in the plant body after sowing and, accordingly, the blight of agricultural crops can be controlled and the growth of the crop can be promoted to improve the productivity of the crop.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to seeds treated with an N-acyl lactam compound and a fluorescent bacterium, and by ensuring the colonization of the fluorescent bacterium on the root surface and within the root after sowing, The purpose is to improve productivity by controlling diseases and promoting growth of agricultural crops.

[0002]

2. Description of the Related Art With the development and spread of biotechnology and the like, variety improvement of vegetables and flowers or seed management technology has been rapidly advanced in recent years, and gradually, quality improvement, yield increase, disease control effect are becoming apparent. . For example, germination is promoted using priming technology in seeds, and in controlling disease, fluorescent bacteria and plant growth promoting root germs are used.
Attempts have been made to control diseases and promote growth by seed treatment using (PGPR). Attempts have also been made to combine seed treatment technology and antagonistic microorganism utilization technology.

When conditioning cucumber and tomato seeds with shale powder, the antagonistic filamentous fungus Trichoderma
By adding Hasenum (Trichoderma harzianum), Psium
It is also reported that the number of die-outs after emergence by Ultimam (Pythium ultimum) is reduced. However, in disease control and growth promotion, fertilization, irrigation, sterilization, insecticide, weeding, and other cultivation management still occupy a large weight, and it cannot be said that a sufficient effect is necessarily expressed.

[0004]

SUMMARY OF THE INVENTION Accordingly, the present inventors
A useful fluorescent bacterium that lives in the root of the crop, by using seeds introduced at the stage of seed priming or conditioning, in order to express the plant growth promoting effect and disease onset suppressing effect of fluorescent bacteria, As a result of various studies, the present invention has been completed.

So far, polyethylene glycol, mannitol, various salt solutions and the like have been used for seed priming, and it is known to be an effective technique for promoting germination and the like. Therefore, the present inventors have attempted colonization of the fluorescent bacteria to the seeds by simultaneous treatment with seed priming for the purpose of labor saving and combined effect, but the degree of colonization is low,
In many cases, fluorescent bacteria were killed, and when the bacterial density was increased or after long-term treatment, poor germination of seeds and a decrease in fluorescent bacterial activity were observed. In rare cases, even if fixing is performed, the manifestation and duration of the effect are unstable, and various problems remain for practical use. In order to solve these problems, the target fluorescent bacteria are colonized at the seed stage, and after the seeding, it is necessary to treat the colonized fluorescent bacteria so that they can live in the seed or the living body of the plant. is necessary.

[0006]

[Means for Solving the Problems] Therefore, as a result of extensive studies on a substance which does not show bactericidal activity against fluorescent bacteria at the stage of seed priming and conditioning and is effective for fixing fluorescent bacteria, It has arrived.
That is, the present invention relates to seeds obtained by treating with N-acyl lactam compounds and fluorescent bacteria.

[0007]

The present invention will be described in more detail below. Fluorescent bacterium used in the present invention, Pseudomonadaceae family according to the classification of Bergey (Pseudomonadaceae) or Azotobacteraseae family (Azotobacteraceae) belongs to, a bacterium having a water-soluble fluorescent dye-producing ability as physiological characteristics. Is.

Regarding the N-acyl lactam compounds,
As a result of many years of research, we focused on the physiologically active function of this compound and used it as a plant growth regulator for plants, and for bacteria, Gram-positive such as actinomycetes, root nodule bacteria, bihizobacteria, and methane fermenters. We proposed the use as a promoter for the growth or substance metabolism of microorganisms that have the ability to differentiate into bacteria or cells. We also proposed a bacteriostatic effect against Gram-negative bacteria and filamentous fungi. These physiological activities are effects on the primary metabolism of plants,
For microorganisms, the main effect was on secondary metabolism.

It is well known that the mechanism of disease protection inherent in plants is regulated in the secondary metabolic system, and the present inventors further investigated the effect of N-acyl lactam compounds on the secondary metabolism of plants. Was added. As a result, N-
Acyl lactam compounds showed remarkable plant secondary metabolism control action in the saturated concentration range. In particular, it was found that it has an action of promoting metabolism of antimicrobial substances to the outside of roots for solanaceous crops. In addition, N-acyl lactam compounds do not show bactericidal activity against fluorescent bacteria and type cultures separated from roots in the saturated concentration range, and suppress cell division but do not affect substance metabolism or cell growth. A promoting action was observed. The present invention has been completed based on these findings.

Examples of the N-acyl lactam compound used in the present invention include 1- [2- (4-human oxyphenyl) ethanoyl] -2-phenylidone and 1- [3- (4-human oxyphenyl) fluorophenyl] -2. -Pepertone, 1- [3-
(4-Hydroxyphenyl) cinnamoyl] -2-phenyldiphenyl, 1- [2- (3,4-dihydroxydiphenyl) ethanoyl] -2-phenylidone, 1- [3- (3,4-dihydroxydiphenyl) Prophalonoyl] -2-peripherone, 1- [2- (4-humanoxyphenyl) ethanoyl] -2-proroidone, 1- [3- (4-humanoxyphenyl) pronoyl] -2-proroidone, 1
A good example is-[3- (3,4-diethyloxyphenyl) propanoyl] -2-prolyldenone.

Seeds treated with N-acyl lactams and fluorescent bacteria can be prepared by the following method. In addition, these processes can be performed either simultaneously or intermittently. Examples of the treatment method include a soaking method in which seeds are immersed in a mixed solution of an N-acyl lactam compound and a fluorescent bacterium, and a fine powder having a slight hardness such as N-acyl lactam compound, a fluorescent bacterium, silica, and zeolite. The seed coat abrasion method of stirring and mixing seeds and seeds, or the soaking decompression method of performing the soaking method under reduced pressure can be used. Alternatively, the seed may be treated with an aqueous solution of the N-acyl lactam compound or a powder containing the N-acyl lactam compound, and then treated with a suspension of fluorescent bacteria or a powder containing fluorescent bacteria, The reverse order may be sufficient. The most desirable method is a soaking decompression method in which seeds are added to a mixed solution of an aqueous solution of an N-acyl lactam compound and a suspension of fluorescent bacteria to decompress. As a carrier used for pulverization, silica, diatomaceous earth, zeolite, perlite, vermiculite, sea sand and the like can be mentioned as preferable examples.

The concentration of the N-acyl lactam compound used in the solution is preferably 50 mg / L or higher. The density of fluorescent bacteria depends on the nature of the bacteria used and its application and is not limited, but it is desirable to use 10 ⁶ cells / ml or more in the case of solution and 10 ⁵ cfu / g or more in the case of solids. . The proportions of N-acyl lactam compounds and fluorescent bacteria used for seeds are
It cannot be specified unconditionally because it depends on the type of acyllactam compound or fluorescent bacterium, the state of treated substance, etc., but it is generally 1 mg of N-acyllactam compound per 1 ml of seeds There is 10 ⁸ c
About ells is preferable.

[0013]

EXAMPLES Examples of the present invention will be further described below. Table 1 shows N-acyl lactam compounds used in the examples. In the examples, these N-acyl lactam compounds are represented by substance numbers. In addition, the fluorescent bacteria used in the examples are shown in Table 2, and each strain is represented by a strain code in the examples.

[0014]

[Table 1]

[0015]

[Table 2] Note) * 1: Separation from the root of tomato (variety, Momotaro) * 2: Separation from the root of Sansho

(Example 1) Substance Nos. (1) to 1 shown in Table 1
The N-acyl lactam compound of (8) was prepared in an aqueous solution of 100 mg / L concentration, sterilized by filtration, and then adjusted to 10 ⁸ cells / ml, and the fluorescent bacteria (A) and (B) of Table 2 were prepared. The suspensions of (C), (D) and (F) were mixed at the same volume ratio to obtain a seed treatment mixture. After sterilizing tomato seeds (variety: House Momotaro) with 1% sodium hypochlorite aqueous solution and 80% ethanol aqueous solution,
1 ml of the seeds were dipped in 10 ml of the mixed solution for seed treatment and subjected to a soaking depressurization treatment under a reduced pressure of 10 mmHg for 6 hours (invention group). In place of the mixed solution for seed treatment, (A), (B), (C), (D), (F) cell suspension and sterile water in the same manner as described above, using a soaking decompression treatment. It carried out (control area and untreated area).

After the treatment, the seeds in each plot were washed with sterilized water to obtain seeds of the present plot, the control plot and the untreated plot. Seed the treated seeds of each section on white agar medium (excluding sucrose) and in dark aerobic condition.
It was kept at 28 ° C for 5 days, and the progress of germination was investigated. Next, the germinated seeds in each cultivated area were cultivated for 2 weeks in an artificial weather machine under aerobic conditions. Changes in germination rate during the cultivation period were measured, and the numbers of fluorescent bacteria on the root surface and the roots of the seedlings after cultivation were measured. To measure the number of fluorescent bacteria, the cultivated seedlings were extracted from the medium, and about 1 g of the seedling roots were placed in 10 ml of 0.005% aerosol OT (manufactured by American Cyanamid) aqueous solution at 10000 rpm.
A root grind solution was prepared by homogenizing for 0 minutes, and the prepared solution was diluted and then subjected to a pouring method using a potato-dextrose agar medium. The results are shown in Tables 3 and 4.

[0018]

[Table 3]

[0019]

[Table 4]

(Example 2) In the same manner as in Example 1, the N-acyl lactam compounds of substances Nos. (1) to (8) shown in Table 1 were used.
After preparing an aqueous solution with a concentration of 00 mg / L and performing filter sterilization,
Fluorescent bacteria (A), (B), (C) of Table 2 prepared at ⁸ cells / ml,
The same volume as the bacterial cell suspension of (D) was mixed to obtain a mixed solution for seed treatment. Komatsuna seeds (manufactured by Tohoku Co., Ltd.) are sterilized with a 1% sodium hypochlorite aqueous solution and an 80% ethanol aqueous solution, and then 1 ml of the seeds is immersed in 10 ml of the seed treatment mixed solution, and the pressure is reduced to 10 mmHg for 2 hours for immersion soaking. Treatment was carried out (invention section). Similarly, the immersion pressure reduction treatment was performed using the bacterial cell suspensions (A), (B), (C), and (D) and sterile water (control and untreated).

After the treatment, the seeds in each plot were washed with sterilized water to obtain seeds in the present plot, the control plot and the untreated plot. Seed the treated seeds of each section on white agar medium (excluding sucrose) and in dark aerobic condition.
It was kept at 20 ℃ and 28 ℃ for 2 days, and the change of germination rate during the cultivation period was measured. Next, the germinated seeds of each plot germinated at 28 ° C were cultivated for 2 weeks in an artificial weather machine under aerobic conditions. The number of fluorescent bacteria on the root surface and the roots of the seedlings after cultivation was measured. To measure the number of fluorescent bacteria, extract the cultivated seedlings from the medium, put about 1 g of the seedling roots in 10 ml of 0.005% aerosol OT (manufactured by American Cyanamid) aqueous solution, and homogenize at 10 000 rpm for 10 minutes to obtain a root-grinding solution. Was prepared, and the prepared solution was diluted and the mixture was subjected to a pour-in method using a potato-dextrose agar medium. The results are shown in Tables 5 and 6.

[0022]

[Table 5]

[0023]

[Table 6]

(Example 3) In order to compare and examine the effect of treated seeds when soil was used, fluorescent bacteria which can be detected by re-separation as (B) in Table 2 and
(E) was selected. Detection method from soil and plants (D) can be re-detected by the presence or absence of blue-white fluorescent precipitates around colonies when grown on potato dextrose agar containing 5 mg / l crystal violet. . In addition, it was confirmed by the same method that the fluorescent bacteria having the same characteristics were not present from the plug raising seedling-raising soil and the bacterial wilt disease-causing soil used in this example. (E) is 200 mg / l streptomycin sulfate, 100 mg / l nalidixic acid, 10
When grown on King B medium containing 0 mg / l sodium ampicillin and further grown on potato dextrose agar, it can be re-detected depending on whether or not a yellow pigment is produced on the colony. In addition, it was confirmed by the same method that the fluorescent bacteria having the same characteristics were not present from the plug raising seedling-raising soil and the bacterial wilt disease-causing soil used in this example.

The (D) and (E) shown in Table 2 were suspended in a 1% sodium alginate aqueous solution to prepare a cell suspension of 10 ⁹ cells / ml. 20 v / v% of this bacterial cell suspension was added to fine sea sand and mixed to prepare a bacterial cell-containing powder. Of the N-acyl lactam compounds shown in Table 1, (1) was dissolved in acetone.
0.5w / v% solution of the compound of (2) was added to silica powder at 10w / w.
%, And the solvent was removed while mixing to prepare an N-acyl lactam compound-containing powder. Cell-containing powder and N
-The acyllactam compound-containing powders were mixed in the same volume to obtain seed treatment powder (invention group). As the control group, the bacterial cell-containing powder and the N-acyl lactam compound-containing powder were used. For the untreated section, the same volume mixture of fine sea sand and silica powder was used.

These powders were added to the tomato seeds (cultivar: large Fukuju) whose surface had been sterilized in the same manner as in Example 1 in an amount of 10 times the volume, and the mixture was subjected to rotary mixing treatment at 80 rpm for 30 minutes. After heat treatment (150 ° C., 15 minutes) of a commercially available soil for growing plugs for raising seedlings, the treated seeds in each section were sown, and the seedlings were raised at an average seedling raising temperature of 40 ° C. for 3 weeks. After raising the seedlings, the fluorescent bacteria on the root surface and in the root were separated and cultured by the same method as in Example 1, and then replicated in the above-mentioned discrimination medium, and the number of isolated bacteria (D) and (E) was measured. The plug seedlings of each plot were planted in a tomato wilt disease-causing soil having a tomato wilt disease bacterial density of 10 ⁶ to 10 ⁷ cfu / g (soil), and the disease suppressive effect was tested by a morbidity survey 3 weeks after the planting. Table 7 also shows the numbers of fluorescent bacteria on the root surface and in the roots after the plug raising and the results of the morbidity survey.

[0027]

[Table 7] Note) Disease severity: Disease severity = {(morbidity index x number of strains) / (10 x number of surveyed strains)} x 100. The morbidity index was death = 10, general wilt = 5, and partial wilt = 2. Control value: Control value = {(the degree of disease in the untreated area-the degree of disease in the test area) / the degree of disease in the untreated area} × 100.

Example 4 Using soil as in Example 3, the effect on plant growth was examined. Table 2 (D) and (E), which can be separated and identified from the plug soil and the potting soil, were used as the test fluorescent bacteria. Of the N-acyl lactam compounds shown in Table 1, the compounds (6) and (7) were prepared in a 100 mg / l aqueous solution to give an N-acyl lactam compound aqueous solution. The cell suspension (Example 3) and an aqueous solution of the N-acyl lactam compound were mixed in the same volume to give a seed treatment solution (invention group). As a control, a bacterial cell suspension and an aqueous solution of N-acyl lactam compound were used. Sterile water was used as the untreated section.

As in Example 1, 1 ml of surface-sterilized tomato seeds (variety: large Fukuju) was dipped in 10 ml of each child treatment solution and treated at 20 ° C. for 6 hours. The treated seeds were subjected to plug raising in the same manner as in Example 3. Then, the seedlings were transplanted to potting medium, the cultivation was continued for 2 more weeks, and the growth was investigated. The results are shown in Table 8.

[0030]

[Table 8] * Total root length: Displayed as total root length by the line crossing method.

[0031]

INDUSTRIAL APPLICABILITY The seed of the present invention has a fluorescent bacterium which has a plant growth promoting property at the seed stage or an effect of suppressing the disease caused by phytopathogenic fungi, and which is established even after sowing. Since it lives in the plant or in the living body of the plant, it is possible to improve the productivity by controlling the diseases of the crops and promoting the growth.

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Taizo Akiyama 331-9 Kamizume, Yoneda-cho, Takasago-shi, Hyogo (72) Minoru Okumura 1406-1 Shinnobe, Beppu-cho, Kakogawa-shi, Hyogo

Claims (2)

[Claims] 1. A seed obtained by treating with an N-acyl lactam compound and a fluorescent bacterium. 2. An N-acyl lactam compound is 1- [2-
(4-Humanoxyphenyl) ethanoyl] -2-hydroxyphenyl, 1- [3- (4-humanoxyphenyl) propanoyl] -2-hydroxyphenyl, 1- [3- (4-humanoxyphenyl) cinnamoyl] -2-phosphoryl, 1 -[2- (3,4-Dimethyloxyphenyl) ethanoyl] -2-phenylidene, 1- [3- (3,4-Dimethyloxyphenyl) propanoyl] -2-phenylidene, 1- [2- (4 -Human oxyphenyl) ethanoyl] -2-prolydone, 1- [3- (4-human oxyphenyl) propanoyl] -2-prorolydone, 1- [3- (3,4-dihydroxyphenoxy) phenoyl] -2-proroidone The seed of claim 1, which is