JPH10218715A - Seed powder coating composition of bacterium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain both a seed powder coating composition of bacterium excellent in promoting effects on growth of plant and seeds subjected to powder coating with the composition. SOLUTION: In this seed powder coating composition of bacterium containing a useful bacterium and a carrier, the composition is mixed with a bacterium belonging to the genus Azospirillum in the ratio of preferably 10<3> -10<11> bacteria in 1g of the carrier. Seeds are coated with the seed powder coating composition of bacterium.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dressing composition for microbial seeds and seeds, and more particularly to a dressing composition for microbial seeds having an excellent plant growth promoting effect and a seed to which the above composition is dressed.

[0002]

2. Description of the Related Art For the purpose of sterilizing seeds, promoting germination, promoting growth, etc., as a seed dressing agent to be attached to seeds at the time of use or a seed coating agent for pre-coating seeds, chemical synthesis agents have been used. Has been researched and developed and put into practical use. However, there is a concern that the above-mentioned chemically synthesized drug may cause emergence of resistant bacteria to the drug, safety at the time of use, phytotoxicity to plants, and environmental pollution.

[0003] On the other hand, in recent years, microorganisms useful for plants have been included because of their advantages that they have no phytotoxicity to plants, do not remain in crops, and do not adversely affect the environment if they remain in soil. Attempts have been made to improve agricultural productivity using microbial materials. Representative examples of such useful microorganisms include rhizobia, bacteria belonging to the genus Azospirillum and Pseudomonas, photosynthetic bacteria,
Fungi belonging to VA mycorrhizal fungi, Trichoderma and the like are known, and some of them have already been put to practical use.

[0004] However, these useful microorganisms are often mixed with a carrier and used as a microbial material, for example, mixed with a cultivation soil for raising seedlings at the time of raising seedlings of plants, or used in cultivation fields. At present, few are used as microbial seed-dressing materials for dressing seeds, and bacteria belonging to the genus Azospirillum have never been used as microbial seed-dressing materials. In addition, the microbial seed dressing materials known so far cannot be said to have a sufficient effect of application, for example, a plant growth promoting effect.

[0005]

DISCLOSURE OF THE INVENTION The present invention has been made in view of the above, and has as its object to provide a microbial seed dressing composition having an excellent plant growth promoting effect and a seed coated with the composition. Make it an issue.

[0006]

Means for Solving the Problems The present inventor has conducted intensive studies on useful microorganisms for use in a microbial seed dressing composition in order to solve the above-mentioned problems, and as a result, using a bacterium belonging to the genus Azospirillum as the useful microorganism. By doing
It has been found that the growth of plants when the microbial seed dressing composition is applied is remarkably promoted, and the present invention has been completed.

[0007] That is, the present invention is a microbial seed dressing composition comprising a useful microorganism and a carrier, wherein the useful microorganism includes a bacterium belonging to the genus Azospirillum.

[0008] Specific examples of the content of bacteria belonging to the genus Azospirillum in the microbial seed dressing composition of the present invention include a content of about 10 ³ to 10 ¹¹ individuals per 1 g of the carrier.

[0009] In the microorganism seed dressing composition of the present invention, it is preferable that the useful microorganisms include useful microorganisms other than those belonging to the genus Azospirillum. Examples of such useful microorganisms include rhizobia, trichoderma and trichoderma. Bacteria belonging to the genus can be preferably mentioned.

[0010] Further, the microorganism seed dressing composition of the present invention comprises:
When the composition contains a useful microorganism other than a bacterium belonging to the genus Azospirillum, the ratio of the population of the bacterium belonging to the genus Azospirillum to the population of other useful microorganisms contained in the composition is 10%.
It is preferably 0: 1 to 1: 100.

[0011] The present invention further provides seeds coated with the microbial seed dressing composition of the present invention.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail.
First, useful microorganisms contained in the microorganism seed dressing composition of the present invention will be described.

(1) Useful Microorganism The microbe seed dressing composition of the present invention is characterized by containing a bacterium belonging to the genus Azospirillum (hereinafter referred to as "Azospirillum fungus") as a useful microorganism.

Azospirillum is a kind of Gram-negative obligate aerobic bacterium having a nitrogen fixing ability. The azospiriram bacterium used in the present invention is not particularly limited as long as it is a microorganism belonging to the genus Azospiriram and having a growth promoting effect on a plant, and specifically, azospiriram brasiliens, azospiriram lipoferram, azospiriram halopreferance And azospiriram-amazonense. Of these, azospirilum brasilence is preferred.

The microbial seed dressing composition of the present invention can further contain useful microorganisms other than the above-mentioned azospirillum as useful microorganisms. Such useful microorganisms are not particularly limited as long as they are generally microorganisms that inhabit the soil and exert a useful effect on plants. Specifically, the genus Azorizobium, Pseudomonas, Rhizobium, Shinorhizobium, Photorhizobium, Bacillus, Bradyrhizobium, Agrobacterium, Streptomyces, Xanthomonas, Lactobacillus, Aeromonas, Anabena, Frankia Genus, Rhodopseudomonas, Trichoderma, Glomus, Aspergillus, Penicillium, Rhizopus, Fusarium, Gliogradium, Gigaspora, Scutelospora, Nostock,
Microorganisms belonging to the genus Azotobacter (hereinafter, for each microorganism, for example, "microorganisms belonging to the genus Azorizobium" are abbreviated to "Azorizobium fungi").

In the microbial seed dressing composition of the present invention, one or more of these useful microorganisms can be used as long as the effect of the azospirillum is not impaired. When two or more kinds of microorganisms are used in combination, it is preferable to appropriately select a combination and a compounding amount that do not impair the usefulness of each microorganism with respect to a plant.

Also, useful microorganisms other than the above-mentioned azospirillum bacteria used in the microorganism seed dressing composition of the present invention are preferably rhizobia, sinorhizobium, photorhizobium, bradyrhizobium, azorhizobium and other rhizobia, trichoderma and the like. Is mentioned.

The rhizobia such as Rhizobium, Sinorhizobium, Photorhizobium, Bradyrhizobium and Azorhizobium are gram-negative bacteria which infect roots of plants to form nodules and have a growth promoting effect on plants. It is not particularly limited as long as it has, and specifically,
Rhizobium melilotti, Rhizobium trifolii, Rhizobium reguminosarum, Rhizobium fazeolii, Rhizobium lupini, Rhizobium friday,
Rhizobium lotti, Rhizobium galega, Rhizobium hakawi, Photorhizobium thompsonam, Brasilizobium japonicum, Azorizobium kaurino dance.

The Trichoderma fungus is a fungus belonging to the genus Trichoderma and is not particularly limited as long as it has a growth-promoting action on plants. Specifically, Trichoderma pyride, Trichoderma reesei,
Trichoderma pseudoconing, Trichoderma coningi, Trichoderma harzianum, Trichoderma hamatum and the like can be mentioned.

The medium used for cultivation of the azospirillum and other useful microorganisms is not particularly limited as long as it is a medium suitable for the growth of these microorganisms. For example, a liquid medium is preferable for azospirillum and rhizobia.
In addition, about azospirillum bacteria, when DL-malic acid is added to a culture medium, the number of bacteria in a culture medium can be increased.
Specifically, for culturing Azospirillum, an RC medium (DL-malic acid: 5 g / L, KOH: 4.8 g / L,
Yeast extract: 0.5 g / L, K ₂ HPO ₄ : 0.5 g /
_{L, MgSO 4 · 7H 2 O} : 0.2g / L, NaCl:
_{0.1g / L, FeCl 3 · 6H} 2 O: 0.015g /
L, pH 7.0). For the culture of rhizobial bacteria, a YM medium (mannitol: 10 g / L, yeast extract: 0.4 g / L, K ₂ HPO ₄ : 0.5 g / L, MgS
_{O 4 · 7H 2 O: 0.2g} / L, NaCl: 0.1g /
L, pH 7.0). These media, the Rhizobium or Azospirillum bacterium 10 ⁸ cells / L
After inoculation at a rate of 30%, shaking culture is performed 180 times per minute at 30 ° C. for 24 hours, and then the cells are collected by a centrifuge to obtain cells.

When the above-mentioned Trichoderma is used in the dressing composition of the present invention, the cells are cultured in a medium capable of growing the cells of Trichoderma, such as a solid component derived from a plant, a sugar or nitrogen source. It is possible to collect and use cells from a culture cultured in a porous body or the like impregnated with, preferably a culture containing Trichoderma in which spores are sufficiently formed by culture. Furthermore, it is also possible to collect spores of Trichoderma bacterium from the culture by a usual method and use this in the present invention. Further, a Trichoderma bacterium culture in which spore formation is sufficiently performed can be obtained by solid culture using a flask or the like. In particular,
A bran medium mixed with sand (volume ratio of brass: sand: water =
1: 3: 1), after inoculating Trichoderma spores at a rate of 10 ⁸ / L, and then culturing at 25 ° C. for 20 days.

Next, the carrier contained in the microbial seed dressing composition of the present invention together with the useful microorganisms will be described.

(2) Carrier As the carrier contained in the microbial seed dressing composition of the present invention, an organic or inorganic material usually used as a microbial material can be used as a main material. Specifically, inorganic materials such as Akadama clay, calcined Akadama clay, Kanuma soil, Kuroboku soil, attapulgite, vermiculite, montmorillonite, perlite, zeolite, peat moss,
Organic materials such as charcoal, pulp, oil cake, fish cake, bone meal, blood meal, shell fossil, crab shell, humus and the like can be used. These inorganic and organic materials can be used alone or as a mixture of two or more as the carrier of the microorganism seed dressing composition of the present invention, but the carrier used in the present invention contains an organic material. Is preferred.

Here, in the above-mentioned inorganic substances, organic substances and the like, which are listed as constituents of the carrier, the particle shape is not particularly limited.
Those having a size of about 5 mm to about 5.0 mm are preferably used in the microorganism seed dressing composition of the present invention.

The above-mentioned carrier used in the microbial seed dressing composition of the present invention may contain various trace components in addition to the above-mentioned inorganic and organic materials, if necessary, to exert the effects of the microbial seed dressing composition of the present invention. It is possible to mix in a range that does not impair. As such a trace component, specifically, a pH adjuster such as lime, magnesia, calcium carbonate, a fungicide such as metalaxyl, oxadixyl, manzeb, a bactericide such as thiuram, and a molybdenum, cobalt, iron, etc. And the like. Specifically, the pH of the carrier is adjusted to 5.0 to 8.0 as an appropriate amount of the pH adjuster.
The amount to be adjusted to such an extent can be, for example, an appropriate amount of the above-mentioned antifungal agent, specifically about 0.001 to 0.2% by weight based on the total amount of the carrier.

Further, the above-mentioned carrier is added at an appropriate ratio, for example, at a ratio of about 20 to 90% by weight based on the total amount of the carrier.
Moisture can be contained, which is preferable in the microbial seed dressing composition of the present invention.

The microbial seed dressing composition of the present invention containing the useful microorganism and the carrier is described below.

(3) Microbial seed dressing composition of the present invention The microbial seed dressing composition of the present invention is a microbial seed dressing composition comprising the useful microorganisms containing the azospirillum and the carrier.

The content of azospirillum in the microbial seed-dressing composition of the present invention is, specifically, 1 g of a carrier.
The content of about 10 ³ to 10 ¹¹ individuals can be mentioned, but in the microbial seed dressing composition of the present invention, the content of about 10 ³ to 10 ¹⁰ individuals per 1 g of carrier is preferably used. More preferably, 10 ⁴ to 1 g of the carrier.
The content of about 10 ⁹ individuals can be mentioned.

Further, the microorganism seed dressing composition of the present invention comprises:
As described above, it is possible to contain a microorganism other than azospirillum as a useful microorganism, and it is preferable. In this case, the ratio of the population of azospirillum to other useful microorganisms contained in the composition is 100: 1-1: 100
It is preferred that Here, when the microorganism seed dressing composition of the present invention contains two or more kinds of useful microorganisms other than Azospirillum, an individual of useful microorganisms other than Azospirillum used for calculating the ratio of the number of individuals is used. The number is the total number of the two or more useful microorganisms. The number of useful microorganisms other than the above azospirillum usually means the number of cells, but when spores are used like Trichoderma, it means the number of spores.

The dosage form of the microorganism seed dressing composition of the present invention is
It is not particularly limited, and can be the same as the dosage form of the seed dressing composition usually used for seeds of cultivated crops. Depending on various dosage forms, the usual microbial seed dressing composition contains In addition, components other than those described above can be arbitrarily contained within a range that does not impair the effects of the microorganism seed dressing composition of the present invention.

Further, the seeds coated with the microbial seed dressing composition of the present invention provided by the present invention will be described.

(4) Seeds The present invention provides seeds that have been dressed with the microbial seed dressing composition of the present invention. The seed to which the microorganism seed dressing composition of the present invention is applied is not particularly limited as long as it is a seed of a cultivated crop.

Specific examples include seeds of crops selected from legumes, brassicaceae, asteraceae, solanaceae, acalyptaceae, cucurbitaceae, acari, lily, gramineous and the like. Among them, soybean, adzuki bean, peas, green beans, peanuts, fava beans, clover, alfalfa, vetch (above, legume crop), komatsuna, Chinese cabbage, cabbage, radish, turnip, cauliflower (above, cruciferous crop), lettuce , Syngiku, burdock (more than Asteraceae crops), tomato, eggplant, pepper, potato (more than solanaceous crops), spinach (Rhabaceae crops), watermelon,
Cucumber, pumpkin, melon (more than Cucurbitaceae crop), celery, carrot (more than Cucurbitaceae crop), leek, onion,
The seeds of crops such as asparagus (above, lily crops) and corn (grass crops) are cited as the seeds of the crops that have remarkable effects when cultivated using the microbial seed dressing composition of the present invention. be able to.

The method of dressing the seeds of the above-mentioned crops with the microbial seed-dressing composition of the present invention and the amount to be dressed can be the same as in the case of using the usual microbial seed-dressing composition. For example, when the soybean is dressed with the microbial seed dressing composition and the seed of the present invention,
In a container such as a plastic bag or a PET bottle, soybeans and about 1.5 to 3.0 mg of the microbial seed dressing composition per one soybean are placed and shaken, or soybeans and soybeans are placed on a sheet or tray. It is preferable to put about 2.0 to 8.5 mg of the microbial seed dressing composition per 1 g, and to coat them by mixing them using a spoon or the like.

The seed of the present invention coated with the microbial seed dressing composition thus obtained can be sown and cultivated in the same manner as a normal seed. The cultivation soil may be any of field soil, paddy field soil, artificial soil, and the like, and may be appropriately set according to the plant to be applied. Sand and artificial soil are preferred.

[0037]

Embodiments of the present invention will be described below.

[0038]

[Production Example] Culture of Azospirillum, Rhizobium and Trichoderma Azospirillum brasiliensis (ATCC 29145)
Is a RC medium (DL-malic acid: 5 g / L, KOH:
4.8 g / L, yeast extract: 0.5 g / L, K ₂ HP
O ₄ : 0.5 g / L, MgSO ₄ .7H ₂ O: 0.2 g / L
L, NaCl: 0.1g / L, FeCl 3 · 6H 2 O:
(0.015 g / L, pH 7.0), 100 mL of medium was dispensed into a 500 mL Sakaguchi flask, and then separately liquid-cultured inoculum was inoculated at 10 ⁷ cells per flask, and this was inoculated 180 times per minute. 3 in a shaking incubator
After culturing at 2 ° C. for 24 hours, the cells were collected by centrifugation.

The rhizobial bacteria (B. rhizobium japonicum ATCC 10324) were grown on a YM medium (mannitol: 10).
g / L, yeast extract: 0.4 g / L, K ₂ HPO ₄ : 0.
_{5g / L, MgSO 4 · 7H} 2 O: 0.2g / L, NaC
1: 0.1 g / L, pH 7.0), and cultured under the same conditions as for Azospirillum, followed by centrifugation.

Trichoderma harzianam (ATCC6)
0850) was cultured in a bran medium mixed with sand (volume ratio bran: sand: water = 1: 3: 1) at 25 ° C. for 20 days, and the culture was aseptically dried with warm air at 30 ° C. The flying spores were collected by a dust collector and collected.

[0041]

Examples 1 to 6 Microbial seed dressing composition The water content was adjusted to 70% by weight as a carrier.
Attapulgite having a particle size of 0.1 mm to 1.0 mm was used. The azospirillum bacterium obtained in the above production example was used for 1 g of the carrier in 10 ⁵ individuals in Example 1, 10 ⁶ individuals in Example 2, 10 ⁷ individuals in Example 3, and 10 ⁷ individuals in Example 4.
⁸ individuals give Example in 5 10 ⁹ individuals, respectively so as to be 10 ¹⁰ individuals in Example 6 homogeneous mixture to six microorganisms seed dressing composition. These were designated as microbial seed dressing compositions 1 to 6 in order. Further, azospirillum was added to the carrier at a rate exceeding 10 ¹¹ individuals / g, but uniform mixing could not be performed at such a rate.

<Evaluation of the microbial seed dressing composition of the present invention>
Each of the six types of microbial seed dressing compositions 1 to 6 obtained in each of the above examples was adhered to 40 seeds of the bean variety Sapporo midori at a ratio of 2.0 mg per grain. That is, after putting 40 grains of the bean seed and 80 mg of the microbial seed dressing composition 1 into a plastic bag having a size enough to allow 40 grains of the bean seed to move freely, and after putting a little air into the plastic bag to create a space, The mouth was closed with a rubber band, and the plastic bag was sufficiently shaken up, down, left and right, and the bean seed was dressed with the microorganism seed dressing composition 1. For the remaining microbial seed dressing compositions 2 to 6, seed dressing was performed in the same manner. In addition, as a control, only the above carrier was adhered to 40 seeds of the edible bean variety Sapporo midori in the same manner as described above at a rate of 2.0 mg per grain.

For cultivation of Edamame, red clay was used as cultivation soil for cultivation, and a black vinyl pot with a diameter of 9 cm was used as a container. To 20 black vinyl pots, red clay was placed leaving a gap of 2 cm at the top, and two seeds of Edamame seeds to which the microbial seed dressing composition 1 obtained in Example 1 was attached were sown. Such pots were prepared in 20 pots for each of the soybean seeds to which the remaining microbial seed dressing compositions 2 to 6 were attached and the control soybean seeds, respectively. These pots were placed in a vinyl greenhouse, irrigated once a day, and maintained at 25 ° C in the day and 15 ° C at night. After the seeds germinated, the seeds were thinned out to one per pot and grown for one month.

One month after the germination, all the seedlings were pulled out,
After washing the soil attached to the roots, cutting the aerial part and the root part, measuring the stem length and obtaining an average of 20 strains for each test plot, then separately separating the aerial part and the root part of the sample at 105 ° C for 1 day After drying, the weight was measured and the average of 20 strains was determined for each test plot. Table 1 shows the results. Here, each numerical value is a relative value with the control value being 100. The T / R ratio is
Aboveground weight / root weight.

[0045]

[Table 1]

As is evident from the results, all of the microbial seed dressing compositions of the present invention containing the azospirilum bacterium obtained in Examples 1 to 6 have a growth promoting effect on soybean.

[0047]

Examples 7 to 18 Microbial seed dressing composition The water content was adjusted to 70% by weight as a carrier.
Vermiculite having a particle size of 0.1 mm to 1.0 mm was used. The azospirillum bacterium obtained in the above production example was used for 10 g of the carrier, 10 ⁵ individuals in Example 7, 10 ⁶ individuals in Example 8, 10 ⁷ individuals in Example 9, and 1 in 1 g of the carrier.
0 ⁸ individuals, ¹⁰⁹ individuals in Example 11, in Example 12 1
0 ¹⁰ individuals were uniformly mixed to obtain six kinds of microbial seed dressing compositions. These were designated as microbial seed dressing compositions 7 to 12 in order.

Separately from this, the carrier obtained in the above-mentioned Production Example was obtained.
10 g of carrier for 1 g of carrier ^FiveEqual to be an individual
Further, in Example 13, the above
Zospirillum bacterium per 10 g of carrier^FiveIndividual, Example
14 for 10⁶Individual, 10 in Example 15⁷Individual, Example
16 is 10⁸Individual, 10 in Example 17⁹Individual, Example
18 for 10^TenEvenly mix each to become an individual
Six types of microbial seed dressing compositions were obtained. These in order
It was set as the biological seed dressing composition 13-18.

<Evaluation of the microbial seed dressing composition of the present invention>
Each of the twelve kinds of microbial seed dressing compositions 7 to 18 obtained in each of the above Examples was adhered to 40 seeds of the bean variety Sapporo midori at a ratio of 2.5 mg per grain. That is, after putting 40 seeds of the bean seed and 100 mg of the microbial seed dressing composition 7 into a plastic bag large enough to freely move 40 seeds of the bean seeds, and after putting a little air into the plastic bag to create a space, , Close the mouth with a rubber band,
The plastic bag was sufficiently shaken up, down, left and right, and the bean seeds were dressed with the microorganism seed dressing composition 7. For the remaining microbial seed dressing compositions 8 to 18, seed dressing was performed in the same manner.

The cultivation of soybean is carried out in exactly the same manner as in the case of using the microbial seed dressing compositions 1 to 6, and the root weight and the above-ground weight after cultivation are measured in the same manner. The average of 20 shares was determined. Furthermore, in this evaluation test, the colonization density of Azospirillum to the roots was measured as follows, and the average of 20 strains was determined for each test plot.

0.1M MgC in a plastic bottle
50 ml of l _2, 1 g of root before drying and glass beads having a diameter of 0.5 mm were vigorously stirred for 10 minutes, and then allowed to stand for 1 minute. After standing, the collected supernatant was diluted 10000-fold and diluted with RC agar medium (DL-malic acid: 5 g / L, KOH:
4.8 g / L, yeast extract: 0.5 g / L, K ₂ HP
O ₄ : 0.5 g / L, MgSO ₄ .7H ₂ O: 0.2 g / L
L, NaCl: 0.1g / L, FeCl 3 · 6H 2 O:
(0.015 g / L, agar: 20 g / L, pH 7.0) was calculated from the number of colonies appearing.

Table 2 shows the results. Here, the root weight and the above-ground part weight are relative values with the value obtained by cultivating and measuring using the microbial seed dressing composition 7 being 100. Regarding the colonization density of Azospirillum, the result of the microbial seed dressing composition 13 was the result of the microbial seed dressing composition 7, the result of the microbial seed dressing composition 14 was the microbial seed dressing composition 8, The result of the dressing composition 15 is the microbial seed dressing composition 9, the result of the microbial seed dressing composition 16 is the microbial seed dressing composition 10, and the result of the microbial seed dressing composition 17 is the microbial seed dressing. The result of the composition 11 of the microbial seed dressing composition 18 is a relative value with the value obtained by cultivating and measuring using the microbial seed dressing composition 12 as 100.

[0053]

[Table 2]

As is evident from the results, the microbial seed dressing composition of the present invention, which further contains rhizobia in addition to the azospirillum bacterium, shows the microbial seed powder of the present invention, which contains only the azospirillum bacterium at the same concentration. It has a greater growth promoting effect on soybeans than the clothing composition.

[0055]

Examples 19 to 30 Microbial seed dressing composition The carrier was adjusted to have a water content of 70% by weight.
Montmorillonite having a particle size of 0.1 mm to 1.0 mm was used. In Example 19, the azospirillum bacterium obtained in the above Production Example was used in an amount of 10 ⁵ individuals per 1 g of the carrier,
Then, 10 ⁶ individuals in Example 21, 10 ⁷ individuals in Example 21, and Example 22
In Example 23, 10 ⁸ individuals and Example 23, 10 ⁹ individuals In Example 24, 10 ¹⁰ individuals were uniformly mixed to obtain six types of microbial seed dressing compositions. These were designated as microbial seed dressing compositions 19 to 24 in order.

Separately from the above, the spores of Trichoderma bacterium obtained in the above-mentioned production example were uniformly mixed with the carrier in an amount of 10 ⁸ per gram of the carrier. To 1 g of carrier
⁵ individuals, 10 ^{6 in} Example 26, 10 in Example 27
⁷ individuals, 10 ^{8 in} Example 28, 10 in Example 29
^Nine individuals, and in Example 30, 10 ¹⁰ individuals were uniformly mixed to obtain six kinds of microbial seed dressing compositions.
These were sequentially referred to as microbial seed dressing compositions 25 to 30.

<Evaluation of the microbial seed dressing composition of the present invention>
Each of the twelve kinds of microbial seed dressing compositions 19 to 30 obtained in each of the above Examples was attached to 40 corn seeds at a ratio of 1.8 mg per one. That is, after putting 40 grains of the bean seed and 72 mg of the microbial seed dressing composition 19 into a plastic bag large enough to allow 40 corn seeds to move freely, and after putting a little air into the plastic bag to create a space, The mouth was closed with a rubber band, and the plastic bag was sufficiently shaken up, down, left and right to coat the corn seeds with the microorganism seed dressing composition 19. For the remaining microbial seed dressing compositions 20 to 30, seed dressing was performed in the same manner.

Corn cultivation and root weight after cultivation,
The measurement of the above-ground weight is performed in exactly the same manner as in the case of using the above-mentioned microbial seed dressing compositions 1 to 6, and the fixing density of azospirillum to roots is determined by using the above-mentioned microbial seed dressing compositions 7 to 18. Was performed in exactly the same manner as described above, and the average of 20 strains was determined for each test section. Table 3 shows the results.

Here, the root weight and the above-ground weight are relative values with the value obtained by cultivation and measurement using the microorganism seed dressing composition 19 being 100. Regarding the colonization density of Azospirillum, the result of the microbial seed dressing composition 25 is the result of the microbial seed dressing composition 19, the result of the microbial seed dressing composition 26 is the microbial seed dressing composition 20, The result of the dressing composition 27 is the microbial seed dressing composition 21,
The result of the microbial seed dressing composition 28 is the microbial seed dressing composition 22, the result of the microbial seed dressing composition 29 is the microbial seed dressing composition 23, and the result of the microbial seed dressing composition 30 is the microbial seed dressing composition. Cultivated using each of the dressing compositions 24,
It is a relative value with the measured value being 100.

[0060]

[Table 3]

As is evident from the results, the microbial seed dressing composition of the present invention containing Trichoderma in addition to the azospirillum was all of the microbial seed powder of the present invention containing only Azospirillum at the same concentration. The effect of promoting the growth of corn is greater than that of the clothing composition.

[0062]

Industrial Applicability The microbial seed dressing composition of the present invention has an excellent plant growth promoting effect. When seeds coated with the microbial seed dressing composition of the present invention are used for crop cultivation, plant growth is promoted, and an increase in yield or a shortened cultivation period can be expected.

Claims (6)

[Claims] 1. A dressing composition for microbial seeds comprising a useful microorganism and a carrier, wherein the useful microorganism comprises a bacterium belonging to the genus Azospirillum. 2. The dressing composition for microbial seeds according to claim 1, wherein the content of bacteria belonging to the genus Azospirillum is 10 ³ to 10 ¹¹ individuals per 1 g of the carrier. 3. The microbial seed dressing composition according to claim 1, wherein the useful microorganism contains a useful microorganism other than a bacterium belonging to the genus Azospirillum. 4. The microbial seed dressing composition according to claim 3, wherein the useful microorganism other than the bacterium belonging to the genus Azospirillum is a bacterium belonging to the rhizobia and / or the genus Trichoderma. 5. The composition according to claim 1, wherein the ratio of the number of bacteria belonging to the genus Azospiriram to the number of other useful microorganisms is 10 or more.
The microbial seed dressing composition according to claim 3, wherein the ratio is 0: 1 to 1: 100. 6. A seed coated with the microbial seed dressing composition according to claim 1.