CN109757488B

CN109757488B - Microbial seed pelleting coating composition

Info

Publication number: CN109757488B
Application number: CN201910124557.9A
Authority: CN
Inventors: 林庆胜; 冯夏; 尹飞
Original assignee: Plant Protection Research Institute Guangdong Academy of Agricultural Sciences
Current assignee: Plant Protection Research Institute Guangdong Academy of Agricultural Sciences
Priority date: 2019-02-20
Filing date: 2019-02-20
Publication date: 2022-03-04
Anticipated expiration: 2039-02-20
Also published as: CN109757488A

Abstract

The invention relates to a microbial pelleted seed coating composition comprising one or more active substances which are microbially active ingredients and an inactive substance which comprises starch, sprayed onto the surface of the seed, wherein the microbially active ingredients are homogeneously distributed in the starch. The invention utilizes the starch to specifically promote the growth and the propagation of the active ingredients of the microorganisms, prolongs the lasting period and the residual period of the active ingredients of the microorganisms, can continuously and stably ensure the disease prevention and insect killing effects of the active ingredients of the microorganisms, ensures the germination capacity of seeds even under the conditions of barreness and serious diseases, and obviously improves the germination rate and the germination vigor of the seeds.

Description

Microbial seed pelleting coating composition

Technical Field

The present invention relates to a coating agent for seed coating, and more particularly to a granulated coating composition for microbial seeds, which comprises a microbial insecticidal active ingredient and starch, wherein the starch in the composition has the characteristic of promoting the growth and reproduction of the microbial active ingredient, and provides a strong insecticidal effect to the seeds even under particularly poor conditions.

Background

The seed coating is that substances such as bactericides, insecticides, plant growth regulators, coloring agents, fillers and the like are adhered to the surface of seeds by using an adhesive, the weight of the coated seeds is increased, and the seed coating is suitable for mechanical sowing. The pelleting is used as a main seed coating type, small-sized seeds are easy to drift along with wind, the seeds are not easy to enter the soil and are fixed to germinate and grow, the weight of the seeds after pelleting and coating is increased, so that the seeds are easy to fix in the soil, the problem that the seeds drift along with the wind during aerial seeding can be solved, and meanwhile, the nutrition can be increased through pelleting, the moisture is kept, and a micro soil environment of the seeds is formed.

The pesticide is used as the most important active substance pesticide in the coating agent, can effectively prevent and control underground pests and diseases, is coated in the seed coating agent on the surface of the seeds by selecting a proper pesticide, after the coated seeds are sowed, the coating layer absorbs water and swells, the active substances of the pesticides are slowly released and contact the seeds and the surrounding soil, so that germs and pests are killed, meanwhile, due to the slow release of the active substances of the pesticides, the pesticide can exert the effect for a longer time compared with a method of spraying the pesticide on leaf surfaces and the like, the disease can be prevented for a longer time, the seeds can be protected from the diseases for a longer time in the seedling stage of the germination and growth stages of the seeds, and the survival rate of the seedlings is improved. The prevention and control effect of most seed coating agents on plant diseases and insect pests in the seedling stage can reach 70-95%, and the treatment effect of the common agents is about 50-80%. How to keep the pesticide continuously and effectively exerting the insecticidal efficacy in the whole seedling stage of the seeds depends on whether the seeds can be continuously and effectively protected in the whole seedling stage. Meanwhile, with the banning of highly toxic pesticides and the attention on food safety, biological environment-friendly high-efficiency pesticides are widely concerned. However, the biological pesticide, especially the active ingredient of the microorganism, has become a bottleneck restricting the development of the pesticide due to the short residual period of the field application, and how to improve the pesticidal effect is the biggest problem faced by the manufacturers.

Disclosure of Invention

The object of the present invention is to provide a microbial pelletization coating composition with which, after coating, the pelletized seeds of the present invention maintain a more lasting and effective disease resistance effect than the coated microbial active ingredient alone due to the growth and reproduction promoting effect of the starch specificity on the microbial active ingredient. The invention aims to keep the high-efficiency functions of preventing diseases, controlling pests, strengthening seedlings and the like of the pesticide in the coating agent even if the seeds are stored for a long time and after a seedling stage, and stabilize and improve the germination capacity and the emergence rate of the seeds.

The present invention relates to a pelleted seed. Hereinafter, the term refers to that small-sized seeds (generally, seeds with a thousand seed weight of less than 10 g) or seeds with irregular surfaces (such as flat, awn, barbed, etc.) are attached to the surfaces of the seeds by a pelleting machine, and spherical particles with certain size, certain strength and smooth surfaces are formed on the basis of not changing the biological characteristics of the original seeds, so that the large granulation of the small-sized seeds is achieved; some seeds such as long and sharp seeds can be coated into an approximate spherical shape. The advantages of pelleted seeds over non-pelleted seeds are: mechanical sowing is facilitated, and the sowing performance is improved; the stress resistance of the seeds is enhanced, diseases and pests are treated simultaneously, and the growth of crops is promoted; is beneficial to the aerial seeding operation.

In order to achieve the purpose, the invention adopts the technical scheme that: a pelleted seed coating composition comprising one or more active substances comprising a microbially active ingredient and an inactive substance comprising a starch sprayed onto the surface of the seed, wherein the microbially active ingredient is homogeneously distributed in the starch.

Generally, the microbial active ingredient of the invention is selected from one or more of bacillus subtilis, bacillus amyloliquefaciens, pseudomonas, azotobacter, metarhizium anisopliae, beauveria bassiana, paecilomyces fumosoroseus and bacillus thuringiensis. The microbial active component has good poisoning effect on more than 100 kinds of pests such as Lepidoptera, Diptera, Coleoptera and the like and animal and plant nematodes. The most commonly used control objects with special effects are: the insecticidal composition has good control effects on pests such as lepidoptera, hymenoptera, diptera, coleoptera and the like, and has ovicidal action. In addition, the seed dressing agent also has special effect on seed dressing of soybeans and prevention and control of underground nematodes.

A pelleted seed coating composition for use according to the invention wherein the amount of microbially active ingredient is 2-20%, preferably 2-10%, more preferably 2-6% by weight of the coating composition.

Meanwhile, in order to ensure the lasting activity of the microbial active ingredients, the microbial active ingredients are uniformly distributed in the starch in proper amount, the uniform distribution is favorable for the continuous and stable growth and reproduction of the microbial active ingredients and the more comprehensive distribution around the seeds, and the used amount depends on the type of the applied seeds and the growth environment of the seeds. Wherein the microbially active ingredient represents 5-30% by weight of the starch, the skilled person will be able to determine the appropriate amount depending on the active substance and the type of seed to be applied.

Preferably, the starch raw material is selected from one of corn, sweet potato, mung bean, rice, cassava, wheat and plant tuber or any mixture thereof. Derivatives of these plant-derived starches are also included, including hydrolyzed, etherified, cross-linked, grafted, oxidized or chemically modified, and the like.

Generally, microbial active ingredients have different physical states when used as pesticides, such as suspoemulsions, powders. The method ensures the uniform distribution of the microbial active ingredients in the starch, allows the starch to continuously provide nutrition for the microbial active ingredients, and preferably selects the powder, so that the microbial active ingredients can be uniformly dispersed in the starch, and the starch can wrap the microbial active ingredients in an all-around manner.

The plant growth regulator is added in a liquid form, and can improve the seed vigor, promote the seed germination and improve the seedling uniformity. The plant growth regulator is itself a liquid and is added to the seed surface by means of spraying. The plant growth regulator added may be a mixture of one or more plant growth regulators, 0.2-5% by weight of the total coating composition of the plant growth regulator. Wherein the plant production regulator is selected from one or more of gibberellin, indoleacetic acid, kinetin, salicylic acid, naphthylacetic acid, sodium naphthenate, ABT rooting powder, and humic acid. Especially preferred is the combination of gibberellin and indoleacetic acid added to the seed coating composition to increase the endogenous hormone levels in the crop, enhance plant growth, and increase crop stress resistance.

The invention selects calcium peroxide as the oxygen releasing agent, the calcium peroxide and water can slowly release oxygen under the action of the calcium peroxide and the water to provide oxygen for the microbial active ingredients and rice seeds, thereby not only prolonging the growth activity period of the microbial active ingredients, but also improving the conditions of seedling emergence and root pricking in the field. Wherein the weight of the calcium peroxide accounts for 0.5-10%.

Preferably, the pelleted seed coating agent of the invention further comprises a water-retaining agent which is a high molecular polymer with super-strong water absorption capacity, can rapidly absorb water and slowly release water, and because the growth and propagation environment of the microbial active ingredients needs to maintain certain humidity, in order to ensure that the pelleted seed coating agent can maintain certain water needed by the microbial active ingredients by means of the water-retaining agent under the drought extreme conditions. The water retention agent is selected from one or more of water absorbent resin, seaweed, polyvinyl alcohol and polyacrylamide type mixture, and preferably polyvinyl alcohol.

Similarly, the field control effect of the microbial active ingredient preparation can be influenced by ultraviolet rays (UV) in sunlight, and the surface structure and the form of the parasporal crystal can be damaged by long-time ultraviolet irradiation, so that the primary structure and the three-dimensional structure of the parasporal crystal protein are changed and denatured, and the parasporal crystal protein cannot be degraded into toxin protein with insecticidal activity, and the insecticidal activity is lost. Wherein lignin, humic acid, Congo red, folic acid and p-aminobenzoic acid can prevent ultraviolet ray damage. The invention selects lignin preferably, and the lignin has a certain protection effect on spores and crystals, thereby prolonging the residual period of the active ingredients of the microorganisms.

Suitable inactive substances are added into the coating composition as fillers, the role of the fillers is mainly to increase weight and improve the mechanical sowing performance of the pelletized seeds, generally, the fillers are required to have the functions of air permeability, water retention and fertilizer retention and also have certain compressive strength, and the fillers are usually mixed by a plurality of components according to a certain proportion and are selected from the following groups: bentonite, turf, montmorillonite, attapulgite, sepiolite, a pelleted seed coating composition kaolin, calcium hydroxide, calcium phosphate, zeolite powder, gypsum, perlite, diatomite, silica, bagasse and granite.

Preferably, the inactive ingredients of the seed coating composition of the present invention further include an ingredient as a binder, which is selected in consideration of binding effect, convenience in use, acidity and alkalinity, low toxicity and environmental protection, source and cost. Which is selected from one or more of the following groups: polyvinyl alcohol, clay, methylcellulose, hydroxypropyl cellulose, acacia, sodium carboxymethylcellulose, polyvinylpyrrolidone, polyvinyl acetate, polyoxyethylene, polysaccharide, tragacanth, sodium alginate, ethyl cellulose acetate, butyl cellulose, gelatin, polyisobutylene, silica gel, etc. In the seed coating composition, the above binder is present in an amount of 20 to 60% by weight based on the total weight of the composition.

The seeds in the invention are rape, grass (including pasture and lawn grass), tobacco seeds, Chinese cabbage, rice, cotton, sesame, corn, broccoli or flower seeds and the like. The pelletizing process includes rolling pelletizing process and flowing pelletizing process. The rolling granulation method utilizes the adhesion performance between the surface characteristics of the seeds and the inner surface of the rotary pot body, the seeds continuously roll in the rotary pot body along with the rotation of the rotary drum body, and active substances and inactive substances are added simultaneously; the flow granulation method is to make seeds flow and roll in a cylinder by using air flow to form a suspension state, and simultaneously to apply active substances and inactive substances to the seed flow, so that the surface of the seeds is adhered with a coating agent by floating and rolling to form a shell with a certain thickness. One coating method of the pelleted seed coating composition of the present invention is by tumbling granulation.

Compared with the prior art, the invention has the beneficial technical effects that: the invention uses the active ingredients of the microorganisms uniformly distributed in the starch as a part of the coating agent, so that the starch can comprehensively coat the active ingredients of the microorganisms, and the starch can specifically promote the growth and the reproduction of the active ingredients of the microorganisms and prolong the vegetative growth period, thereby prolonging the effective period and the residual effective period, ensuring that the active ingredients of the microorganisms continuously and stably exert insecticidal efficacy, ensuring the germination capacity of seeds under the conditions of barrenness and serious diseases and improving the crop yield.

Detailed Description

Example one

Test seeds: rapeseed

Seed pelleting process flow: the method comprises the following steps of seed selection (awn removal or grinding) → seed disinfection → wetting by an adhesive → mixing with a medicament or an auxiliary agent → adding a filling agent for stirring → pill forming → hot air drying → size screening and grading → quality inspection → mass weighing → bagging → warehousing, wherein a rolling granulation method is adopted, and a rotary seed pelleting machine is utilized, and the method comprises the following specific steps: placing the selected seeds into a horizontal roller, spraying an adhesive while the seeds continuously roll along with the roller to prevent the seeds from being adhered to each other and keep a certain humidity on the surface, then adding starch uniformly mixed with bacillus subtilis powder and spraying a plant growth regulator, then adding a filling agent, pelleting, and then sending into drying equipment for drying.

Coating composition formulations were prepared according to table 1, composition a1 being the experimental group and composition B1 and composition C1 being both the control group.

Table 1:

example 2

The test seeds and the seed pelletization process were the same as in example one.

Coating composition formulations were prepared according to table 2, composition a2 being the experimental group and composition B2 and composition C2 being both the control group.

Table 2:

the seed germination capacity is measured by adopting sand bed germination, the pelletized seeds are placed in a 12cm multiplied by 6cm small germination box which is paved with fine sand, the seeds are lightly pressed into the sand bed by fingers to be just immersed in the sand, each formula is repeated for 3 times, 50 seeds are repeated for each formula, the room temperature is kept at about 25 ℃, and the germination measurement is carried out by irradiating for 12 hours every day. The number of sprouts (based on cotyledon emergence) was observed and counted every day, the germination rate was counted 3 days after the start of the test, the germination rate was counted 7 days after the start of the test, and the results of the germination rate and germination rate measured in the above examples I and II are shown in tables 3 and 4, wherein

Table 3: example one rapeseed germination results

Test group	Percentage of germination (%)	Germination vigor (%)
			Composition A1	94.67	89.66
Composition B1	84.27	79.86
			Composition C1	84.32	79.57

Table 4: germination results of rapeseed as in example two

Test group	Percentage of germination (%)	Germination vigor (%)
			Composition A2	94.69	89.62
Composition B2	82.18	75.34

As can be seen from tables 3 and 4, after the bacillus subtilis and the starch of the invention are subjected to the synergistic treatment, the germination rate is not lower than 94%, the germination potential is not lower than 89%, and the germination rates are higher than those of other control experimental groups, which indicates that the seed growth can be better promoted only by the combined action of the starch and the bacillus subtilis. As shown in Table 3, the germination rate and germination potential of control group B1 using cellulose and control group C1 not using starch were lower than those of test group C1, indicating that starch is not a substitute for cellulose; as shown in Table 4, Bacillus sphaericus, which is also used as a biopesticide, is used as a control experimental group B2, the germination rate and the germination potential are lower than those of an experimental group C2, which shows that the Bacillus subtilis and the starch also both contain starch, have specific synergistic effect, are irreplaceable by other biopesticides and have better effect on the growth of seeds.

The above description is only a preferred embodiment of the present invention, and is not intended to limit the present invention in any way, and any simple modifications, changes in components and the like made to the above embodiment according to the technical essence of the present invention are within the scope of the technical solution of the present invention without departing from the technical solution of the present invention.

Claims

1. Use of a pelleted seed coating composition for promoting germination of rapeseed, characterized in that: the composition of the pelletized seed coating composition is as follows:

5 percent of bacillus subtilis powder

Starch 12%

2 percent of calcium peroxide

Gibberellin and indoleacetic acid 7%

3 percent of lignin

31 percent of diatomite

40% of polyvinyl alcohol;

the preparation method of the pelletized seeds comprises the steps of adopting a rolling granulation method, placing selected seeds into a horizontal roller, spraying an adhesive while the seeds continuously roll along with the roller so that the seeds are not mutually bonded and the surface keeps a certain humidity, then adding starch uniformly mixed with bacillus subtilis powder and spraying a plant growth regulator, then adding a filler, and drying the pelletized seeds in drying equipment.