CN115316402A

CN115316402A - Trichoderma and dry suspension bactericide and preparation method thereof

Info

Publication number: CN115316402A
Application number: CN202210908287.2A
Authority: CN
Inventors: 吴红渠; 刘芳; 朱志刚; 方伟; 陈伟
Original assignee: Hubei Biopesticide Engineering Research Center
Current assignee: Hubei Biopesticide Engineering Research Center
Priority date: 2022-07-29
Filing date: 2022-07-29
Publication date: 2022-11-11

Abstract

The invention provides a trichoderma, dry suspension bactericide and a preparation method thereof. The preservation number of the trichoderma is CCTCC NO: m2022942. The dry suspension bactericide comprises trichoderma conidium powder, a wetting dispersant, an ultraviolet protective agent, a disintegrating agent, a binder and a carrier; the dry suspension bactericide has the advantages of high conidium survival rate (80.16%), long storage period, quick disintegration, high suspension rate, fine particle size, strong adhesive force, scouring resistance and the like, is an excellent green pesticide, and has huge market development prospect.

Description

Trichoderma and dry suspension bactericide and preparation method thereof

Technical Field

The invention relates to the technical field of microbial pesticide preparation and processing, in particular to a trichoderma and dry suspension bactericide and a preparation method thereof.

Background

Trichoderma (Trichoderma spp.) belonging to the class of fungi Imperfecti, order Hyphomycetales, strobispora material, is distributed worldwide. Widely distributed in the ground substances such as soil, rotten wood and plant residues. Trichoderma has a wide application prospect in the aspects of biological control of plant diseases and environmental protection, and Trichoderma has proved to have better control capability on various soil-borne diseases such as southern blight, phytophthora blight, rice sheath blight and the like, wherein Trichoderma koningii (Trichoderma koningii), trichoderma asperellum (Trichoderma viride) and Trichoderma harzianum (Trichoderma harzianum) are widely applied in control. Many studies indicate that trichoderma is widely distributed in soil, and the trichoderma can parasitize hypha and sclerotium of various plant pathogenic fungi and has the function of promoting plant growth.

Trichoderma longibrachiatum can parasitize various plant pathogenic bacteria such as Sclerotinia, pythium (spp.), rhizoctonia solani and Sclerotinia sclerotiorum (Sclerotinium rolfsii). The trichoderma has multiple action mechanisms of generating antibiotics and toxins, parasitizing, generating cell wall degrading enzymes, synergistic action and the like on plant pathogenic bacteria, and can effectively inhibit the occurrence of plant fungal diseases. Commercial trichoderma granules are reported abroad, and different bacterial strains are prepared into biological preparations for preventing and treating sclerotinia diseases such as pea, soybean, sunflower, rape, lettuce and the like and soil-borne diseases of other greenhouse and field crops.

A dry suspending agent is a new formulation of pesticide and a new formulation processing technology which are researched and developed internationally in the 80 th of the 20 th century. The preparation has granular form which can be rapidly disintegrated and dispersed into high-suspension solid-liquid dispersion system in water, contains no organic solvent, and has good suspension stability, high suspension rate, no dust, and convenient packaging, transportation and use. The dry suspending agent is considered to have the advantages of granules and an ideal pesticide formulation with high dispersion performance of the suspending agent, and becomes a hotspot of new formulation development.

Due to poor biocompatibility of the trichoderma strains to the auxiliary agents, dry suspension preparations of the trichoderma strains are not registered and sold so far, and are not applied in fields in large quantities, so that all the trichoderma dry suspension preparations need to be provided.

Disclosure of Invention

In view of the above, the present invention provides a trichoderma, a dry suspension bactericide and a preparation method thereof, so as to solve or at least partially solve the technical problems in the prior art.

In a first aspect, the present invention provides a trichoderma classified under the name: trichoderma longibrachiatum NBBRC-VWT5, wherein the preservation number of the Trichoderma longibrachiatum is CCTCC NO: m2022942.

In a second aspect, the invention also provides a dry suspension bactericide, which comprises trichoderma conidium powder, and the preparation method of the trichoderma conidium powder comprises the following steps: and (3) activating and culturing the trichoderma until spores are generated, thus obtaining the trichoderma conidium powder.

Preferably, the dry suspension bactericide further comprises a wetting dispersant, an ultraviolet protective agent, a disintegrating agent, a binder and a carrier.

Preferably, the dry suspension bactericide comprises the following components in percentage by mass: 5 to 30 percent of trichoderma conidium powder, 8 to 20 percent of wetting dispersant, 0.1 to 1 percent of ultraviolet protective agent, 2 to 20 percent of disintegrating agent, 1.0 to 10 percent of binder and 24 to 83.9 percent of carrier.

Preferably, the dry suspension bactericide, the ultraviolet protective agent comprises at least one of dextrin, xanthan gum, sodium fluorescein, vitamin C and nano zinc oxide;

and/or the disintegrating agent comprises at least one of cross-linked polyvinylpyrrolidone, cross-linked sodium carboxymethyl cellulose, cross-linked povidone, urea, ammonium sulfate and starch;

and/or the binder comprises at least one of CMC, sodium lignosulfonate, PEG, oxalic acid and dextrin;

and/or the carrier comprises at least one of attapulgite, kaolin, diatomite, bentonite and white carbon black;

and/or, the wetting and dispersing agent comprises at least one of Morwet EFW, k12, MF-5, TERWET1010, WLNO, calcium lignosulfonate, TERSPERSE2700, TERSPERSE 2020, morwet D425, NNO, T36.

Preferably, the dry suspension bactericide comprises the following components in percentage by mass: 5% of trichoderma conidium powder, 12% of wetting dispersant formed by mixing Morwet EFW and calcium lignosulfonate, 3% of cross-linked polyvinylpyrrolidone, 0.2% of nano zinc oxide, 4% of PEG and 75.8% of white carbon black.

Preferably, the dry suspension bactericide comprises the following components in percentage by mass: 20% of trichoderma conidium powder, 15% of wetting dispersant formed by mixing TERWET1010 and TERSPERSE2700, 4% of crospovidone, 0.3% of vitamin C, 5% of sodium lignosulfonate and 55.7% of diatomite.

Preferably, the spore content of the dry suspension bactericide of the trichoderma conidium powder is more than or equal to 1 x 10 ¹⁰ The water content per gram is 1.8-2.5%.

In a third aspect, the invention also provides a preparation method of the dry suspension bactericide, which comprises the following steps:

mixing the wetting dispersant, the ultraviolet protective agent, the disintegrating agent, the binder and the carrier, adding water, and then grinding;

and adding the trichoderma conidium powder into the ground material, mixing, and performing spray granulation to obtain the dry suspension bactericide.

Preferably, the preparation method of the dry suspension bactericide comprises the steps of mixing the wetting dispersant, the ultraviolet protective agent, the disintegrating agent, the binder and the carrier, adding water, and grinding to obtain a particle size of 18-22 μm;

adding the trichoderma conidium powder into the ground material, stirring and mixing for 20-60 min at 8000-15000 r/min, and performing spray granulation to obtain the dry suspension bactericide.

Compared with the prior art, the trichoderma, the dry suspension bactericide and the preparation method thereof have the following beneficial effects:

the dry suspension bactericide comprises trichoderma conidium powder, a wetting dispersant, an ultraviolet protective agent, a disintegrating agent, a binder and a carrier; the dry suspension bactericide has the advantages of high conidium survival rate (80.16%), long storage period, quick disintegration, high suspension rate, fine particle size, strong adhesive force, scouring resistance and the like, is an excellent green pesticide, and has huge market development prospect.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the embodiments or the prior art descriptions will be briefly described below. It is obvious that the drawings in the following description are only some embodiments of the invention, and that for a person skilled in the art, other drawings can be derived from them without inventive effort.

FIG. 1 is a photograph of Trichoderma longibrachiatum NBBRC-VWT5 of the present invention taken by microscopic examination with an optical microscope (400X);

FIG. 2 is a photograph of a positive PDA plate of Trichoderma longibrachiatum (Trichoderma longibrachiatum NBBRC-VWT 5) of the present invention;

FIG. 3 is a photograph of a back side PDA plate of Trichoderma longibrachiatum (Trichoderma longibrachiatum NBBRC-VWT 5) of the present invention;

FIG. 4 is a tree diagram of the ITS rRNA gene sequencing evolution of Trichoderma longibrachiatum (NBBRC-VWT 5) of the present invention;

FIG. 5 is a graph showing the particle size distribution of the dry suspension bactericide prepared in example 1 of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention. It is to be understood that the embodiments described are only a few embodiments of the present invention, and not all embodiments.

The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be obtained by a person skilled in the art without any inventive step based on the embodiments of the present invention, are within the scope of the present invention.

The embodiment of the application provides trichoderma which is separated from soil in forest parks of China of Shen nong's shelf in Hubei province. The strain grows well on a PDA culture medium, a colony has a pustular structure on a PDA plate, pustules with different sizes turn green after being mature, the color of the reverse side is white or yellow, the colony is in a tree shape under microscopic examination, clustered conidia are arranged at the top of a petiole, the conidia are in an ellipsoid shape, and the colony morphology and gene sequencing evolutionary tree are shown in attached figures 1, 2, 3 and 4. Identified by China center for type culture Collection and named according to the classification of trichoderma: trichoderma longibrachiatum (Trichoderma longibrachiatum NBBRC-VWT 5). At present, the trichoderma is preserved in China center for type culture Collection with the preservation number of CCTCC NO: m2022942, wherein the preservation address is China, wuhan university; the preservation date is 2022, 06 and 29 days.

Based on the same inventive concept, the embodiment of the application also provides a dry suspension bactericide, which comprises trichoderma conidium powder, and the preparation method of the trichoderma conidium powder comprises the following steps: and (3) activating and culturing the trichoderma to produce spores to obtain trichoderma conidium powder.

Specifically, the preparation method of the trichoderma conidium powder specifically comprises the following steps:

s1, firstly, inoculating the preserved trichoderma strains to a PDA culture medium plate, carrying out activated culture under the conditions of 28 ℃ and 12L ⁷ spore/mL of suspension;

s2, adding 1mL of the suspension obtained in the step S1 into a 200mL triangular flask containing 30mL of PD culture solution to ensure that the spore concentration in the culture solution is l x l0 ⁶ Performing shake culture (28 +/-1 ℃,180 r/min) for 48h per mL of spores, transferring into 1000mL of PDA culture solution (PDA is standard fungus culture solution), and continuing the shake culture for 24h to obtain inoculation solution;

s3, weighing 100g of rice, respectively placing the rice in 500ml glass triangular flasks, and mixing the rice in the following ratio according to the weight of the rice (g): water (mL) = 1.5 (i.e. 1.5mL water is added to each g of rice) and water is added for soaking for 30min, and after washing and draining, sterilization is carried out under the following sterilization conditions: sterilizing at 121 deg.C and 0.1MPa for 30 min. After cooling, mixing the trichoderma inoculation liquid (namely the inoculation liquid in the step S2) according to the inoculation amount of 10% of the volume, pouring the inoculated rice material into a culture dish with the diameter of 15cm, and covering the culture dish with a preservative film;

s4, inoculating the rice material at the temperature of 28 +/-1 ℃ and the volume of 12L: culturing to produce spores under the condition of 12D, removing the preservative film, and culturing for 3-5D to obtain a rice culture; freezing and vacuum drying the rice culture to reduce the water content to below 4%, and separating spore powder from rice matrix by using a vibrating screen to obtain trichoderma conidium powder;

wherein, PDA culture medium is potato glucose agar culture medium, PD culture solution is PD liquid culture medium, and the PDA culture medium and the PD culture solution used in the application adopt commercial culture medium/culture solution; 12l.

In some embodiments, a wetting dispersant, a uv protectant, a disintegrant, a binder, and a carrier are also included.

In some embodiments, the dry suspension biocide comprises, in mass fractions: 5 to 30 percent of trichoderma conidium powder, 8 to 20 percent of wetting dispersant, 0.1 to 1 percent of ultraviolet protective agent, 2 to 20 percent of disintegrating agent, 1.0 to 10 percent of binder and 24 to 83.9 percent of carrier.

In some embodiments, the uv protective agent comprises at least one of dextrin, xanthan gum, sodium fluorescein, vitamin C, nano zinc oxide;

and/or the wetting and dispersing agent comprises at least one of Morwet EFW, k12, MF-5, TERWET1010, WLNO, calcium lignosulfonate, TERSPERSE2700, TERSPERSE 2020, morwet D425, NNO, T36.

Wherein CMC is carboxymethyl cellulose, PEG is polyethylene glycol, and Morwet EFW is an Acksonobel import wetting agent; morwet EFW, k12 is sodium dodecyl sulfate, MF-5 is dispersant of Shangyu Zhe chemical industry Co., ltd, TERSPERSE2700 is TERSPERSE2700 dispersant produced by Hounsfield, USA,

in some embodiments, the dry suspension biocide comprises, in mass fractions: 5% of trichoderma conidium powder, 12% of wetting dispersant formed by mixing Morwet EFW and calcium lignosulfonate, 3% of cross-linked polyvinylpyrrolidone, 0.2% of nano zinc oxide, 4% of PEG and 75.8% of white carbon black, wherein the mass ratio of the Morwet EFW to the calcium lignosulfonate is 1.

In some embodiments, the dry suspension biocide comprises, in mass fractions: 20% of trichoderma conidium powder, 15% of wetting dispersant formed by mixing TERWET1010 and TERSPERSE2700, 4% of crospovidone, 0.3% of vitamin C, 5% of sodium lignosulfonate and 55.7% of diatomite, wherein the mass ratio of the TERWET1010 to the TERSPERSE2700 is 1.

In some embodiments, the conidia powder of Trichoderma has spore content of 1 × 10 or more ¹⁰ The water content per gram is 1.8-2.5%.

The embodiment of the application also provides a preparation method of the dry suspension bactericide based on the same inventive concept, which comprises the following steps:

s1, mixing a wetting dispersant, an ultraviolet protective agent, a disintegrating agent, a binder and a carrier, adding water to 70% of the capacity of a grinder, and then grinding;

and S2, adding the trichoderma conidium powder into the ground material, mixing, and performing spray granulation to obtain the dry suspension bactericide.

In some embodiments, after the wetting dispersant, the ultraviolet protective agent, the disintegrating agent, the binder and the carrier are mixed, water is added, and then the mixture is ground to 18 to 22 μm in particle size by a Canadian homogenizer (working pressure 500 to 1200 bar) or a sand mill;

adding the trichoderma conidium powder into the ground material, placing the mixture into a shearing machine, stirring and mixing the mixture for 20 to 60 minutes at 8000 to 15000r/min, and carrying out spray granulation to obtain the dry suspension bactericide.

The dry suspension bactericide of the application is prepared by respectively adding various additives (wetting dispersant, ultraviolet protective agent, disintegrating agent and binder) and carriers into nutrient solution according to a designed proportion, and inoculating 10 ⁶ spores/mL conidium suspension, shaking and culturing at 28 + -1 deg.C and 180r/min for 16h, and sampling and examining germination rate (viable spore rate). The influence of each auxiliary agent is judged according to the germination rate, spores with the length of a germ tube equal to or larger than the diameter of the spores are regarded as germination, and spore aqueous suspension is used as a control (Hong et al, 2001).

The quality standard of the dry suspension bactericide is that the rate of live spores in the dry suspension bactericide is more than or equal to 80.00 percent, the water content is less than or equal to 1.63, the pH value is 6.5, the spore suspension rate is more than or equal to 82.12 percent, the wetting time is 15s, the disintegration time is 78s, the particle size of 90 percent is less than 25.69 micrometers, the average particle size is 10.84 micrometers 1, and the dry suspension bactericide is stored for 60 days at the temperature of 30 ℃ with thermal storage stability; the trichoderma dry suspending agent is qualified. The dry suspension bactericide improves the germination rate and the suspension rate of conidia, has high wetting and disintegrating speed and excellent dispersibility and heat storage stability, and provides a new material for preventing and treating plant diseases.

The following further describes the trichoderma dry suspension fungicide and the preparation method thereof according to the present application with specific examples. This section further illustrates the present invention with reference to specific examples, which should not be construed as limiting the invention. The technical means employed in the examples are conventional means well known to those skilled in the art, unless otherwise specified. Reagents, methods and apparatus employed in the present invention are conventional in the art unless otherwise indicated.

Example 1

The embodiment of the application provides a dry suspension bactericide, which comprises the following components in percentage by mass: 5% of trichoderma conidium powder, 12% of wetting dispersant formed by mixing Morwet EFW and calcium lignosulfonate, 3% of crosslinked polyvinylpyrrolidone, 0.2% of nano zinc oxide, 4% of PEG and 75.8% of white carbon black, wherein the mass ratio of the Morwet EFW to the calcium lignosulfonate is 1.

The preparation method of the dry suspension bactericide comprises the following steps:

s1, mixing the materials except the trichoderma conidium powder, adding a proper amount of water, and putting the mixture into a sand mill to grind the mixture until the particle size is 20 mu m;

s2, adding trichoderma conidium powder into the material ground in the step S1, then placing the material in a shearing machine, mixing the material for 20-60 min at 8000-15000 r/min, and carrying out spray granulation after uniform mixing to obtain the dry suspension bactericide.

Example 2

The embodiment of the application provides a dry suspension bactericide, which comprises the following components in percentage by mass: 20% of trichoderma conidium powder, 15% of wetting dispersant formed by mixing TERWET1010 and TERSPERSE2700, 4% of crospovidone, 0.3% of vitamin C, 5% of sodium lignosulfonate and 55.7% of diatomite, wherein the mass ratio of TERWET1010 to TERSPERSE2700 is 1.

The preparation method of the dry suspension bactericide provided by the embodiment of the application is the same as that of the embodiment 1.

Example 3

The embodiment of the application provides a dry suspension bactericide, which comprises the following components in percentage by mass: 25% of trichoderma conidium powder, 18% of TERWET1010, TERSPERSE 2020 and T36, 5% of ammonium sulfate, 6% of CMC, 0.4% of nano zinc oxide and 45.6% of bentonite, wherein the mass ratio of TERWET1010, TERSPERSE 2020 to T36 is 1.

The particle size distribution of the dry suspension biocide prepared in example 1 is shown in fig. 5. Specifically, in fig. 5, the left ordinate Cmum (abbreviation of statistical distribution) represents the Cumulative distribution, and the right ordinate DiffX (abbreviation of Difference distribution) represents the Difference distribution. In fig. 5, the particle size distribution is shown in table 1 below.

TABLE 1 particle size distribution

Particle size of mum	Content%
		0.823	0.00
1.312	0.17
		2.091	0.97
3.333	3.19
		5.313	8.51
8.470	19.47
		13.50	39.86
21.52	73.33
		34.90	97.54
54.76	100.00

As can be seen from fig. 5, the particle size of the dry suspension biocide, 90% by mass, was <25.69 μm with an average particle size of 10.84 μm.

The dry suspension fungicide prepared in the example 1 has an active spore rate of more than or equal to 80.00%, a moisture content of less than or equal to 1.63% (mass content), a pH value of 6.5, a spore suspension rate of more than or equal to 82.12%, a wetting time of 15s, a disintegration time of 78s, and a thermal storage stability of 60 days at 30 ℃, and is a qualified dry suspension of trichoderma.

Application of dry suspension bactericide

1.1 test materials: apple ring rot pathogen (Physalospora piricola Nose), sclerotinia sclerotiorum (Sclerotinia sclerotiorum), cucumber powdery mildew pathogen (Sphaerotheca cucurbitae), potato late blight pathogen (Phytophthora infestans).

1.2 reagent: the dry suspension bactericide prepared in the embodiments 1 to 3 of the application is 70% chlorothalonil wettable powder and 25% azoxystrobin suspending agent in contrast. It is noted that 70% chlorothalonil wettable powder formulation and 25% azoxystrobin suspending agent formulation are both international pesticide standard universal expressions.

1.3 methods

Pot experiment: respectively transferring the various pathogenic bacteria to a PDA flat plate for activation for 3d, transferring to a PD liquid culture medium, transferring 5 blocks per bottle, culturing for 6d, beating hyphae, measuring light transmittance, carrying out spray inoculation, and carrying out moisture preservation to culture cucumber seedlings until the diseases occur, wherein the light transmittance of the three pathogenic bacteria is 1.0%, 3.2% and 9.6% respectively; the dry suspension fungicide prepared in examples 1 to 3 was diluted 400 times, 800 times and 1600 times, respectively, sprayed to control pathogenic bacteria, and the control effect was checked after 15 days, and the control effect was calculated according to the disease index classification standard (table 2) and the following formula.

TABLE 2 disease level index partition Standard

Grade of disease	Disease condition
		0	Has no symptoms
1	The disease spot area accounts for less than 5% of the whole leaf area
		3	The area of the lesion spots accounts for 6 to 10 percent of the area of the whole leaf
5	The area of the lesion spots accounts for 11-25% of the area of the whole leaf
		7	The area of the lesion spots accounts for 26 to 50 percent of the area of the whole leaf
9	The lesion area accounts for more than 50% of the whole leaf area

Disease index = ([ (. Gradation value. Times. Number of leaves in this case) × 100) ]/(maximum value of gradation. Times. Number of leaves investigated)

Control effect (%) = (CK disease index-treatment disease index) × 100/CK disease index;

wherein CK represents blank control.

1.4 results and analysis

Table 3-in vitro test of the dry suspension fungicide of the present application against physalospora piricola

TABLE 4-in vitro test of the Dry suspension Fungicide of the present application against Sclerotinia sclerotiorum

As can be seen from tables 3-4, the dry suspension bactericide prepared by the method has the control effect on apple ring spot of more than 75 percent and the control effect on sclerotinia rot of rape of more than 65 percent.

Table 5-in vitro test of the dry suspension fungicide of the present application against cucumber powdery mildew

TABLE 6 in vitro test of the Dry suspension Fungicide of the present application against late blight of Potato

As can be seen from tables 5-6, the average control effect of the 1000-time dilution dry suspension bactericide on cucumber powdery mildew is over 70 percent, which is equivalent to the control effect of a control medicament, namely bacillus subtilis; the control effect on the potato late blight is lower than that of chemical pesticide cyazofamid of a contrast agent by 82.8 percent, but the control effect also reaches about 70 percent.

TABLE 7 potted plant test of the Dry suspension Fungicide of the present application for apple ring rot, sclerotinia sclerotiorum

Note: variability (P = 0.01), capital letters after the numbers in table 7, indicating significance at the 99% level.

As can be seen from table 7, the dry suspension fungicide of the present application has various control effects on two plant diseases. The trichoderma conidium powder dry suspending agent has a control effect on apple ring rot and rape sclerotinia rot, although the control effect of the tested trichoderma conidium powder dry suspending agent is not as good as that of a chemical pesticide azoxystrobin, the control effect of 400-fold liquid on apple ring rot diseases is 88%, the control effect difference with azoxystrobin is not obvious (P > 0.01), the control effect on rape sclerotinia rot is poorer than that of the chemical pesticide but is more than 75%, and the trichoderma conidium powder dry suspending agent belongs to the field of microbial pesticides, has no 3R phenomenon of the chemical pesticide, and is an environment-friendly green pesticide.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.

Claims

1. Trichoderma sp, wherein said Trichoderma sp is designated by the classification: trichoderma longibrachiatum NBBRC-VWT5 with a preservation number of CCTCC NO: m2022942.

2. The dry suspension bactericide is characterized by comprising trichoderma conidium powder, and the preparation method of the trichoderma conidium powder comprises the following steps: activating and culturing trichoderma as defined in claim 1 to produce spores, thereby obtaining the trichoderma conidium powder.

3. The dry suspension disinfectant of claim 2 further comprising a wetting dispersant, a uv protectant, a disintegrant, a binder, and a carrier.

4. The dry suspension biocide of claim 3 wherein said dry suspension biocide comprises, in mass fractions: 5 to 30 percent of trichoderma conidium powder, 8 to 20 percent of wetting dispersant, 0.1 to 1 percent of ultraviolet protective agent, 2 to 20 percent of disintegrating agent, 1.0 to 10 percent of binder and 24 to 83.9 percent of carrier.

5. The dry suspension biocide of claim 3, wherein the uv protectant comprises at least one of dextrin, xanthan gum, sodium fluorescein, vitamin C, nano zinc oxide;

6. The dry suspension biocide of claim 5 wherein said dry suspension biocide comprises, in mass fractions: 5% of trichoderma conidium powder, 12% of wetting dispersant formed by mixing Morwet EFW and calcium lignosulfonate, 3% of cross-linked polyvinylpyrrolidone, 0.2% of nano zinc oxide, 4% of PEG and 75.8% of white carbon black.

7. The dry suspension biocide of claim 5 wherein said dry suspension biocide comprises, in mass fractions: 20% of trichoderma conidium powder, 15% of wetting dispersant formed by mixing TERWET1010 and TERSPERSE2700, 4% of crospovidone, 0.3% of vitamin C, 5% of sodium lignosulfonate and 55.7% of diatomite.

8. The dry suspension fungicide according to claim 2, wherein the conidia powder of trichoderma has a spore content of 1 x 10 or more ¹⁰ The water content per gram is 1.8-2.5%.

9. A process for the preparation of a dry suspension biocide as claimed in any one of claims 2 to 8 comprising the steps of:

10. The method for preparing a dry suspension fungicide according to claim 9 characterized in that after mixing the wetting dispersant, the ultraviolet protectant, the disintegrant, the binder and the carrier, water is added and then ground to a particle size of 18 to 22 μm;