CN110800761B

CN110800761B - Signal protein-containing composition for preventing and treating root-knot nematode as well as preparation method and application thereof

Info

Publication number: CN110800761B
Application number: CN201911059238.0A
Authority: CN
Inventors: 岳向国
Original assignee: Weifang University of Science and Technology
Current assignee: Weifang University of Science and Technology
Priority date: 2019-11-01
Filing date: 2019-11-01
Publication date: 2021-06-01
Anticipated expiration: 2039-11-01
Also published as: CN110800761A

Abstract

The invention belongs to the field of agricultural plant protection, and particularly relates to a signal protein-containing composition for preventing and treating root-knot nematodes, and a preparation method and application thereof. The composition comprises an active component A, a signal protein, an active component B, biocontrol bacteria spore powder and an active component C, wherein the active component C is a non-fumigation type nematicide; the invention is a root-knot nematode prevention and control method which takes biological prevention and control as the main part and chemical prevention and control as the auxiliary part, and achieves the purpose of preventing and controlling the root-knot nematode through the combined action of improving the stress resistance of crops, improving the growth vigor of the crops, weakening the infection capacity of the root-knot nematode and the capacity of generating a fixed feeding site after infection and the like; the components of the composition show obvious synergistic effect in a certain proportion range, obviously improves the control effect compared with the single use of the contained components, reduces the dosage of the medicament, and reduces the residue possibly caused by a small amount of synthetic chemical substances to the ecological environment.

Description

Signal protein-containing composition for preventing and treating root-knot nematode as well as preparation method and application thereof

Technical Field

The invention belongs to the field of agricultural plant protection, and particularly relates to a signal protein-containing composition for preventing and treating root-knot nematodes, and a preparation method and application thereof.

Background

Root knot nematode (A), (B) and (C)Meloidogynespp.) is a soil-borne disease that hosts very widely, infecting nearly all vascular plants, and therefore most vegetable crops are good hosts. In the root-knot nematode life cycle, except for infested second instar larvae, other stages are within the plant roots or egg shells. The first instar larva forms in the egg shell, after one molting, the second instar larva with a brooch is formed, and the second instar larva punctures the egg shell with the brooch and enters the soil. The infected second-instar larvae swim in water in soil gaps, suitable hosts are searched and infected into roots at the root tips of the hosts, and cell-to-cell shuttling is stopped near the vascular bundles at the roots. Here, the second instar larva secretes special substances to stimulate the abnormal division of surrounding plant cells to form giant cells, and then the root-knot nematode takes the giant cells as fixed feeding points and does not move any more. The second instar larva can molt for three times to form mature female, male and femaleThe insects escape from the roots and do not harm any more, the female insects absorb water and nutrition at the fixed feeding sites, oocysts are formed by secretion at the tails of the female insects and the epidermis of the roots after 20-40 days, and the generation cycle is completed.

The root-knot nematode absorbs a great deal of host nutrition and moisture through fixing feeding sites, which seriously influences the absorption of the moisture and the nutrition by the host; in addition, mechanical damage to plant roots during root knot nematode infestation also makes the host more susceptible to multiple damages caused by other soil-borne diseases such as damping off and blight, resulting in compound diseases of crops. In the current agricultural production in China, particularly in the process of planting protected facility vegetables, under the influence of various factors such as intensive planting and brand effect, continuous cropping and multiple cropping phenomena widely exist, a good hotbed is provided for the generation propagation of root-knot nematodes, and the root-knot nematode diseases are increasingly serious. According to statistics, the incidence rate of root-knot nematodes in newly-built greenhouses in Liaoning areas, Hebei areas, Shandong areas, Jiangsu areas and other areas is 16.7-20% in 1-2 years, the incidence rate of root-knot nematodes in old greenhouses over 4 years can reach 87.5%, and the incidence degree gradually increases with the increase of the service life of the greenhouses. Root knot nematode disease has become the first disease in protected field vegetable planting. At present, the planting area of facility vegetables in China is about 5900 ten thousand mu, and accounts for 62.7 percent of the total vegetable yield in China. The area of the root-knot nematode disease is about 2000 ten thousand mu, which occupies one third of the total planting area of the vegetable. According to prediction, the loss of Chinese caused by the root-knot nematode damaging vegetables is about 50 hundred million yuan each year, and the root-knot nematode disease becomes an important disease affecting the national civilization.

In consideration of the factors such as human living environment and health, most of the traditional non-fumigation type nematicides are continuously limited in production and use in recent years, so that the varieties of the drugs for preventing and treating the root-knot nematodes available in the market are very rare, the pesticide resistance and the microbial degradation of the nematodes are continuously enhanced due to the repeated use of the nematicides, the prevention and treatment efficiency is reduced year by year, and the root-knot nematode disease becomes the most difficult disease to control in the vegetable planting of Chinese facilities.

In the prevention and control of root-knot nematode diseases, a chemical prevention and control method is always the main mode for preventing and controlling root-knot nematodes in the planting of facility vegetables due to the characteristics of high efficiency, rapidness, convenient use and the like. Biological agents are widely concerned due to the characteristics of green, no residue and the like, but are often used as an auxiliary means for root-knot nematodes due to the defect of unstable control efficiency. Chemical control mainly refers to the use of non-fumigation nematicides, and biological control mainly utilizes some biocontrol bacteria such as nematophagous fungi and some Plant Growth-Promoting Rhizobacteria (PGPR), which can directly or indirectly inhibit the hatching and infection of root-knot nematodes. The major current problems are that most traditional thread killers have been stopped or limited in use for reasons of environmental protection and human health, which directly results in less varieties of thread killers and higher prices registered in the market. The non-fumigation type nematocides registered and used in China by 2019 are only three medicines of fluopyram, abamectin and fosthiazate. In addition, the use of these agents is impaired by the problems of resistance to drugs and microbial degradation that occur with the frequent use of a single variety of agents over a long period of time. Farmers often choose to increase the amount of pesticide used driven by their interest, which results in increased production costs and substandard pesticide residues. The biological agents serving as auxiliary effects in the market at present are mainly based on the fungus predation effect and root probiotic effect, and the control effect of the biological agents depends on the colonization ability of the fungi, so that the control effect is unstable in different habitats. Meanwhile, the use of the common root-knot nematode disease control drug often causes phytotoxicity of crops, and reduces crop biomass and yield. Therefore, an efficient, compound and green control composition containing a biological agent and a non-fumigation type nematicide is urgently needed in the market, the effect of comprehensively treating and efficiently controlling the root-knot nematodes is achieved by acting in different life cycles of the root-knot nematodes, the phytotoxicity can be reduced, the crop activity is promoted, and the purpose of controlling and increasing the yield is finally achieved.

Disclosure of Invention

The invention aims to provide a high-efficiency, composite and green signal protein-containing composition for preventing and treating root-knot nematodes aiming at the current situations that the species of root-knot nematode-resistant medicines in the current market is single, most medicines have long registered time, the drug effect is low, the combination of biochemical pesticides is less and the like.

The invention also provides application of the signal protein-containing composition in the aspects of root-knot nematode prevention and control and vegetable crop growth vigor promotion.

The technical scheme adopted by the invention for realizing the purpose is as follows:

the invention provides a signal protein-containing composition for preventing and treating root-knot nematodes, which comprises A, B, C three active components, wherein the active component A is signal protein, the active component B is anti-microbial spore powder, and the active component C is a non-fumigation type nematicide;

the signal protein is hypersensitive protein-HP; the biocontrol bacterial spore powder is a mixture-SP of a fermentation product and spores obtained by solid fermentation of the pestalotiopsis ficuum; the non-fumigation type nematicide is phosphorothioate non-fumigation type nematicide imicyafos-IM.

Further, the weight ratio of the signal protein to the biocontrol bacterial spore powder to the non-fumigation type nematicide is 1-10: 50-200: 10-100.

The biocontrol bacteria spore powder used by the invention is fermented by the following method:

(1) marking the fig pestalotiopsis strain on a PDA inclined plane, and activating for several generations at 28 ℃;

(2) selecting slant culture bacteria with vigorous growth and bright color, adding 0.5% Tween sterile water, stirring with glass rod, mixing, measuring concentration with counting plate to 10⁷Spore liquid with concentration per ml;

(3) performing solid fermentation by using a plastic bottle, sterilizing and cooling a solid fermentation culture medium, inoculating 6ml of spore liquid, performing solid fermentation at 28 ℃, drying a solid fermentation product for 7 days at 30-35 ℃ for 24 hours, weighing the completely dried fermentation product, and detecting the number of spores to be not less than 10 hundred million/g.

Furthermore, the formula of the solid fermentation medium comprises 50g of bran, 0.5g of glucose, 0.25g of ammonium sulfate and 0.025g of monopotassium phosphate, and 60g of deionized water is added.

The composition provided by the invention is prepared into any formulation allowed in pesticides from active ingredients and pesticide auxiliaries.

Furthermore, the composition comprises 1-85% of active ingredients and 99-15% of pesticide auxiliary agents or auxiliary materials by weight, and forms a pesticide allowable dosage form.

The dosage forms are granules, wettable powder and water dispersible granules.

When the composition provided by the invention is prepared into any formulation allowed on pesticides, the pesticide auxiliary agent is selected from one or more of a carrier, a solvent, a dispersing agent, a wetting agent, an adhesive, a thickening agent, a binding agent or a surfactant.

Furthermore, the composition may also contain other plant growth-promoting rhizobacteria (PGPR) microbial agents.

The invention also provides application of the signal protein-containing composition in the aspects of preventing and treating root-knot nematodes and promoting growth vigor of vegetable crops.

The composition of the present invention may be used in combination with other biocontrol bacteria such as plant growth-promoting rhizobacteria (PGPR), pesticides or fertilizers in order to fully exert the advantageous effects of the present invention.

The fig pestalotiopsis strain used by the invention is purchased from China general microbiological culture collection center with the serial number of CGMCC3.15140, and is obtained by solid pure fermentation of single bacterium after activation.

The composition can be prepared into dosage forms of powder, granular agent, wettable powder, granules and the like which are acceptable in pesticides. Because the biocontrol bacteria and the IM nematicide lack systemic property, the composition provided by the invention directly acts on the underground part of crops when in use, and mainly means root irrigation, hole application and other methods. The composition of the present invention can be prepared into various dosage forms by known methods, and the active ingredients and auxiliary agents, such as solvents, solid carriers, and if necessary, surfactants can be uniformly mixed and ground to prepare the desired dosage forms. The auxiliary agents include dispersing agents, disintegrating agents, binding agents, carriers and the like, are various components which are commonly used or allowed to be used in preparations in the agricultural field, are not particularly limited, and specific components and dosage are determined through experiments according to formula requirements.

The inventor finds that certain fermentation products of endophytic fungi and non-fumigation type nematocides of plants have a synergistic effect when being jointly applied, can effectively inhibit infection of second instar larvae (J2) in a root-knot nematode infection state on host root systems, can play good complementary and synergistic effects in biological control and chemical control under proper conditions, and relatively reduces the application amount of medicines while improving the pesticide effect. The common nematocide usually has weak inhibition effect on egg hatching of root-knot nematodes, and the addition of biocontrol bacteria can well make up the defect. In addition, a certain amount of plant stress-resistant signal protein is added into the composition to generate a remarkable synergistic effect, so that the colonization of the root-knot nematode in a plant body, the formation of root gall and the egg laying number of the root-knot nematode female are further greatly reduced, and the plant vitality is enhanced. The biocontrol bacterium, the nematicide and the signal protein can respectively form a protection effect in three stages of eggs, second-instar larvae of the root-knot nematodes and root gall formed by colonization after infection, so that the scientific mixing of the biocontrol bacterium, the nematicide and the signal protein can achieve a three-dimensional control effect. Research shows that the stress-resistant signal protein, the biological agent and the non-fumigation type nematicide have obvious synergistic effect on the prevention and the treatment of the meloidogyne diseases in facility vegetable planting in a certain compounding ratio range, and have better prevention and treatment effect on meloidogyne incognita harming solanaceae and cucurbitaceae vegetables such as cucumbers, tomatoes and the like in the actual use process.

The invention aims to provide application of a plant stress-resistant signal protein composition in preparing a medicament for preventing and treating diseases caused by vegetable root-knot nematodes and improving crop vigor. The composition provided by the invention has special effect on root knot nematode diseases of vegetable crops.

The invention has the advantages that:

(1) the composition is prepared by effectively compounding plant stress-resistant signal protein, plant endophyte and a small amount of non-fumigation type nematicide with small toxicity and capable of efficiently inhibiting the vitality of the second-instar larvae in the root-knot nematode infection state, and is a root-knot nematode control method mainly based on biological control and secondarily based on chemical control.

(2) The composition can improve the stress resistance of crops, improve the growth vigor of the crops, weaken the infection capacity of the root-knot nematodes and the capacity of generating fixed feeding sites after infection, and achieve the purpose of preventing and treating the root-knot nematodes through the combined action of a plurality of aspects. The use of chemosynthetic drugs is therefore only one part of the control strategy, which reduces the use of chemosynthetic drugs, making the main component of the combination a naturally occurring, non-toxic substance.

(3) In the invention, the components of the composition show obvious synergistic interaction in a certain proportion range, and compared with the single use of the contained components, the composition obviously improves the control effect, reduces the dosage of the medicament and reduces the residue possibly caused by a small amount of synthetic chemical substances to the ecological environment.

(4) Most of the main components in the composition do not directly act on the root-knot nematodes, but the purpose of preventing and treating the root-knot nematodes is achieved only through signal conduction or the complex metabolite and symbiotic action of biological agents, so that the composition is not easy to generate drug resistance, the use frequency of the combined drug is effectively reduced, and the market life of the combined drug is prolonged.

(5) The composition provided by the invention is different from other traditional medicines, not only can be used for efficiently preventing and treating root-knot nematode diseases, but also can be used for reducing phytotoxicity and remarkably improving the activity and biomass of crops.

Drawings

FIG. 1 is a virulence test for IM against second instar larvae.

FIG. 2 is a virulence test of SP on second instar larvae of Meloidogyne incognita.

FIG. 3 is a virulence test of oxamyl against second instar larvae of Meloidogyne incognita.

FIG. 4 shows the inhibition test of different drugs on the hatching of meloidogyne incognita eggs (bracket numbers are the resting rate of hatched larvae).

FIG. 5 is a graph of the effect of combination drug on root node and biomass (stem growth rate in parentheses).

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described with the following specific examples, but the present invention is by no means limited to the following examples. The following description is only exemplary of the type of embodiments of the present invention and is only for the purpose of illustrating the present invention, but should not be construed as limiting the scope of the present invention. It should be understood that any modification, equivalent replacement or improvement made within the spirit and principle of the present invention shall be included in the protection scope of the present invention, and therefore, the protection scope of the present invention shall be subject to the appended claims.

Indoor determination of control of root-knot nematodes by signal proteins, endophytes and non-fumigant nematicides

1. Virulence test for second instar larvae of root-knot nematodes

The most common meloidogyne incognita in the greenhouse warm in winter in north is adopted as the research object (meloidogyne incognita)M. incognita) The nematodes are collected from the diseased tomato roots in the greenhouse of Luzhen town of Shouguang city, and identified as meloidogyne incognita seeds by morphology, isozyme and host tests 2Meloidogyne incognita race 2). Selecting plump large-grain single oocysts from diseased roots, inoculating the oocysts to the roots of tomato seedlings which grow for about 20 days and grow into three leaves and one heart and are cultivated in sterile soil, and preserving and propagating the seeds in a constant-temperature incubator (25 ℃, the illumination is 16h/8 h). Then, taking tomato diseased roots which grow for about 60 days after inoculation, and washing surface soil by tap water; picking 400-600 egg masses under a dissecting mirror, soaking the egg masses in a 0.5% sodium hypochlorite solution, and violently shaking for 3.5 min; the samples were collected in sample bottles after passing through 150, 45 and 25 μm sieves (manufactured by Spectrum Lab, USA) and washing with sterile water several times. Eggs used in the egg hatching inhibition test were freshly extracted within 48 h. When the second-instar larvae are hatched, the extracted eggs are placed in a self-made incubator, sterile water is added into an incubation pool until the eggs just submerge a screen, the incubation pool is sealed by a sealing film, and the eggs are placed in an incubator (27 ℃) for incubation. Larvae that hatched within 24h were collected and immediately used for experimental analysis. In the present example, the signal protein is selected from but not limited to hypersensitive protein, and the biocontrol bacterium is selected from but not limited to pollensThe pestalotiopsis Frondosa and the non-fumigation type nematicide are selected from but not limited to organophosphorus nematicide imicyafos.

The test procedure was as follows:

the test was carried out in 24-well culture plates, and the total volume of the test system per well was 1ml, and the number of second instar larvae per well was 50. + -.10. The treatment concentrations of HP are 0, 0.01, 0.1 and 1mg/L respectively; the SP treatment concentrations are respectively 0, 5, 10, 20 and 40 mg/L; the IM treatment concentrations were 0, 0.1, 1 and 10mg/L, respectively. The reference drug is selected from the drug oxamyl which has been limited in use. The control group was prepared by sterilizing deionized water at high temperature under high pressure instead of the liquid medicine (the same below). Different amounts of HP, SP, IM, oxamyl and sterile water were added to the test system, and after incubation at 27 ℃ for 72h in an incubator, the second instar larvae were observed under a stereomicroscope (Zeiss, Germany, V20) and judged to be incapacitated without visible movement within 20 seconds. Each concentration was repeated 4 times and three trials were made for each treatment. Statistical analysis: the mortality of the second instar larvae carries out nonlinear regression on the drug treatment concentration to obtain a Logistic curve with good fitting degree, and EC is calculated according to a regression equation₅₀The value is obtained. The test method in the subsequent compound test is the same as that of the single-dose test, and concentration gradients of 0, 5, 10, 20 and 40 mg/L and 0, 0.1, 1 and 10mg/L are selected. Calculating each ratio EC₅₀And then, calculating the co-toxicity coefficient (CTC) of the mixture by using a Sun Yunpei method, thereby evaluating the activity of the compound composition on the second-instar larvae of the root-knot nematodes. The co-toxicity coefficient (CTC) of the compound preparation is more than or equal to 120, which shows a synergistic effect; CTC is less than or equal to 80 and shows antagonism; 80 < CTC < 120 showed additive effects. FIG. 1, FIG. 2 and FIG. 3 are the toxicity test curves of IM, SP and oxamyl against second instar larvae, respectively. Indoor virulence determinations for HP, SP and IM on second instar larvae of meloidogyne incognita are shown in table 1.

As shown in FIGS. 1-3, EC of IM, SP and oxamyl on second instar larvae₅₀The values were, respectively, 2.66, 9.71 and 10.65 mg/L. HP has no significant lethal or paralytic effects on second instar larvae (graph not shown), whereas both SP and IM show significant activity on second instar larvae, and the activity is superior to that of the traditional high-potency nematocide oxamyl (oxamyl) which has been limited in use.Furthermore, the action time of the second instar larvae in this test was 72h, whereas the results of the previous experiments showed EC for IM and SP at action times of 2h and 24h₅₀The values are much greater than oxamyl (data not shown), indicating that the main ingredients used in the present composition are less acute toxic and more biologically safe.

Since HP has no toxic effect on second instar larvae, we have only made mixed toxicity assays of fermentates and nematocides to examine the co-toxic effects of both, as in table 1. The results show that when the solid fermentation product of the pestalotiopsis ficuum and the imicyafos are mixed in the ratio of 2:1, 5:1, 10:1 and 20:1, the two products show very remarkable synergistic effects, and the synergistic coefficients are 186.11, 185.03, 169.37 and 120.42 respectively.

TABLE 1 indoor virulence determination of hypersensitive proteins, pestalotiopsis ficuum fermentate and Imicyafos against second instar larvae of Meloidogyne incognita

2. Determination of inhibition effect on hatching of root knot nematode eggs

The test is completed in a microporous plate with 12 holes, fresh southern root knot nematode eggs are taken and placed in the holes, about 500 pieces of southern root knot nematode eggs are placed in each hole, the southern root knot nematode eggs are washed clean by sterile water and then added with liquid medicine, the final concentration of other components is 10mg/L except 1mg/L of HP, and the content ratio of HP, SP and IM in the composition is 1:20: 10. Each treatment was repeated 6 times, and the control was prepared by replacing the drug solution with sterile water. And performing microscopic examination after 7 days, counting the hatched second-instar larvae, and calculating the hatchability and the resting rate of the hatched second-instar larvae. The test was performed in a completely random design, and the test was performed three times. The variance analysis tests the repeatability, and the result shows thatPMore than 0.2, good repeatability.

According to the figure 4, the test result shows that both HP and IM have no obvious inhibition effect on the hatching of the eggs, SP and oxamyl have inhibition effects on the hatching of the eggs, the inhibition effect of SP is strongest, the hatching rate of the eggs is 15.36%, and the inhibition rate reaches 39.41% compared with 25.35% of a control. The resting rate IM of the larvae which hatch under the action of a single agent reaches up to 62.95%, which shows that when the components in the composition of the invention act alone, the action on eggs mainly occurs after the larvae of the second age break the egg shells and escape through the mouth needle. When HP, SP and IM act together, the egg hatchability and the resting rate of hatched second-instar larvae are both lowest, the egg hatchability is reduced to 3.34%, the inhibition rate reaches 86.82%, and the resting rate of hatched second-instar larvae reaches 93.25%. The composition achieves excellent prevention and treatment effects by the dual effects of inhibiting egg hatching and inhibiting the movement of hatched second-instar larvae, and the prevention and treatment effects are obviously superior to those of the traditional nematocide.

3. Test of prevention and treatment effect of pesticide composition on root-knot nematode under potting condition

The test is carried out in an outdoor pot culture, tomato seedlings (tested varieties are 'powder crowns') which grow for 30 days and grow 3 leaves and 1 heart are measured for plant height, root length and fresh weight, and then the tomato seedlings are transferred into a seedling pot filled with sterilized mixed sandy soil (the volume percentage contents of garden soil, turf and river sand are respectively 12.5%, 37.5% and 50%), wherein the diameter of the seedling pot is 6-8cm, and the height of the seedling pot is 16-18 cm. Preparing 1000 Meloidogyne incognita solution of second instar larva (preparation method is the same as above), adding 10ml of the solution, and covering with soil. The test was divided into three groups, control, oxamyl, HP, SP, IM, HP + SP + IM. The test method is as follows: uniformly punching holes at equal intervals around the seedlings, wherein the depth of each hole is 3cm, then uniformly adding 1ml of Nanfang root knot nematode liquid by using a liquid transfer device, then adding the liquid medicine, and covering soil. The concentrations of the treatment groups are 10mg/L, and the content ratio of HP, SP and IM in the composition is 1:20: 10. The control used sterile water instead of drug solution. The trial was a completely random trial design with 12 replicates per treatment. The test was performed under natural conditions with watering as required. After 40 days, samples were taken and the plant height, fresh root weight and root node number were determined. The test is completed in 2017 in 8-10 months.

As shown in figure 5, although HP has no lethal or paralytic effect on the second-instar larvae and has no obvious inhibiting effect on the number of root galls under the outdoor potting condition, HP can obviously promote the growth activity of the tomato infected with the root-knot nematode, and the stem growth rate reaches 94.83 percent, which is obviously better than 85.76 percent of the control. The SP is equivalent to oxamyl in inhibiting root knot, the number of the root knot is 106.58 and 109.31 respectively, and compared with 296.37 of a control, the inhibition rate reaches 64.04 percent and 63.12 percent respectively. IM has the strongest capability of inhibiting root knots in all single agents, the number of the root knots is 54.73, and the inhibition rate is 81.53%. Although the IM and the oxamyl have obvious inhibiting effect on the root node number, the IM and the oxamyl also have obvious phytotoxicity effect, and the stem growth rate is equivalent to that of a control and is 85.66 percent and 83.72 percent respectively. In the treatment of the composition, both the root knot inhibition rate and the stem growth rate are the optimal results in all treatment groups, the root knot number is 1.67, the root knot inhibition rate is 99.43%, the stem growth rate is 116.91% which is equivalent to that of a fully healthy tomato plant, and the composition shows remarkable synergistic effect of all the components.

4. Determination of root-knot nematode control under potted plant conditions by using compositions with different proportions

The test method and test time are the same as above. Six treatment groups and a control group are set in the test, and the control group uses sterile water to replace liquid medicine. The total concentration of the composition in the treatment group was 10 mg/L. The test procedure is the same as above, the number of root knots, the ratio of rhizomes and the stem height are detected after 40 days, the stem growth rate and the root knot inhibition rate are calculated, and the detection results are shown in table 2.

Test results show that the root knot inhibition rate of the signal protein, the biocontrol bacteria and the non-fumigation type nematicide is the highest and reaches 98.02% at the ratio of 1:20:10, the growth activity of plants is close to the highest at the moment, and the stem growth rate is 106.48%. In addition, under the condition that the ratio of 1:100:50-1:10:5 is adopted, the diseased crops can obtain better control effect and better growth vigor, and the ratio has good guiding value for the subsequent field test.

TABLE 2

(II) preparation example of Signal protein-containing composition

Example 1: prevention and treatment of tomato root-knot nematode by wettable powder

The formula is as follows: 20% of the composition (0.65% HP, 13.0% SP, 6.35% IM), 2.5% nonylphenol polyoxyethylene ether (wetting agent), 2.5% of sodium lignosulfonate (dispersing agent), 0.5% of epoxidized soybean oil (suspending agent and stabilizing agent), and the balance of talcum powder (filler). The raw materials are prepared by the process steps of mixing, ultramicro jet milling and mixing. In addition, the 19.35% (13.0% SP, 6.35% IM) wettable powder formulation was the same except that HP was not added. The 5% HP wettable powder only contains 5% HP as an active ingredient, the 19.2% IM wettable powder only contains 19.2% IM as an active ingredient, and the rest auxiliary materials and the auxiliary agents are the same. The 70.1% SP wettable powder only contains 70.1% of a ficus carica pestalum fermentation product, and the rest auxiliary materials and the auxiliary agents are the same.

This example applies to the control of tomato root-knot nematodes. The test is carried out in a tomato greenhouse which is used in Shandong province Shouguang City wailu town of Shouguang city and seriously infected with root-knot nematode diseases for many years in 2018, and the greenhouse soil is detected to be fertile loam, the pH value is 7.1 and is slightly alkaline, and the organic matter content is 2.1 percent. The number of root-knot nematodes in soil above 15cm above the ground surface was determined to be about 19/kg by the Bowman method. The concentration of eggs was about 64 eggs/kg as determined by density gradient centrifugation. The experiment adopts the random repeated design of the cells, 9 ridges are arranged in each cell, the ridge spacing is about 0.8m, 18 tomato seedlings with three leaves and one heart are transplanted in each ridge, and the roots are irrigated immediately after the transplanting according to the random design number. Diluting 20% wettable powder at a ratio of 1:2000 to obtain suspension, and irrigating root with the medicinal liquid of 2.5, 5, 7.5, 10ml for each plant, and the effective component dosages are 300, 600, 900 and 1200g a.i./hm². Other wettable powders are similarly drenched. The prevention and treatment effect is detected after 30 days, and the detection method and the items are the same as above. The results are shown in Table 3.

TABLE 3

According to field test results (table 3), the components in the composition have certain control effect on the root-knot nematodes when being used alone, but the control effect is poor, and the inhibition rate of HP on root knots is 16.89% at least. IM shows good root knot inhibition effect when used alone, the root knot inhibition rate is 80.93%, but the growth effect of crops is poor, and the stem growth rate is equivalent to that of diseased crops. 20% composition wettable powderThe prevention and treatment effect of Meloidogyne incognita is best, the synergistic effect of the composition is very obvious, and the dosage of the effective components is 300-1200 g a.i./hm²The control effect is obvious, the root knot inhibition rates respectively reach 80.58%, 87.92%, 92.57% and 93.12%, the promotion effect on the growth vigor of crops is simultaneously shown, and the stem growth rates are respectively 138.23%, 137.41%, 139.76% and 126.38%.

Example 220% wettable powder for control of cucumber root-knot nematodes

The formula is the same as above, and the embodiment is applied to the control of the cucumber root-knot nematode. The experiment is carried out in a cucumber greenhouse which is used in Shouguang city in Shandong province for many years and seriously infected with the root-knot nematode disease in 2018, 6-7 months, wherein the root-knot nematode in the greenhouse is mainly meloidogyne incognita and contains a small amount of peanut root-knot nematode. The test method and design are the same as above, the test object is cucumber seedling, and the variety is 'Dongwei'. The control effect is detected after 30 days, and the detection items comprise root number, cucumber inverted two-leaf area (leaf area = leaf length x leaf width x 0.743), plant height and cucumber yield. The specific results are shown in Table 4.

TABLE 4

The research result shows that (table 4), the control effect of HP treatment on cucumber root-knot nematode is 28.85% at least, and the control effect of 19.2% IM wettable powder is 82.35% at higher. The 20 percent wettable powder containing the signal protein composition has the best effect on preventing the root-knot nematode of the cucumber and promoting the growth activity of crops, the inhibition rate (prevention effect) on the root-knot nematode of the cucumber can reach 93.24 percent 30 days after one-time application, and the area and the plant height of each leaf of the lodging-two are 73.79cm²And 144.50, show good synergy between the compositions compared to other single agent treatments. When the medicine is used in combination, the cucumber seedling has developed root system, less root knots, vigorous plant growth, no obvious phytotoxicity, safe use and good application value, and the concentration reaches the concentration requirement of industrial development and utilization.

Claims

1. A composition containing signal protein for preventing and treating root-knot nematodes is characterized by comprising A, B, C three active components, wherein the active component A is signal protein, the active component B is anti-microbial spore powder, and the active component C is a non-fumigation type nematicide;

the signal protein is hypersensitive protein-HP; the biocontrol bacterial spore powder is a mixture-SP of a fermentation product and spores obtained by solid fermentation of the pestalotiopsis ficuum; the non-fumigation type nematicide is phosphorothioate non-fumigation type nematicide imicyafos-IM;

the weight ratio of the signal protein to the biocontrol bacteria spore powder to the non-fumigation type nematicide is 1-10: 50-200: 10-100.

2. The signal protein-containing composition according to claim 1, wherein the biocontrol bacterial spore powder is fermented by the following method:

3. The signal-protein containing composition according to claim 2, wherein the solid fermentation medium is composed of 50g of bran, 0.5g of glucose, 0.25g of ammonium sulfate, 0.025g of potassium dihydrogen phosphate, and 60g of deionized water.

4. The signal protein-containing composition according to any one of claims 1 to 3, wherein the composition is prepared from the active ingredient and a pesticide adjuvant in any formulation which is pesticidally acceptable.

5. The signal protein-containing composition according to claim 4, wherein the composition comprises 1-85% by weight of the active ingredient and 99-15% by weight of the pesticide adjuvant or adjuvant.

6. The signal protein-containing composition according to claim 4, wherein the dosage form is granules, wettable powder or water dispersible granules.

7. The signal protein-containing composition according to claim 4, wherein the pesticide adjuvant is one or more selected from a carrier, a solvent, a dispersant, a wetting agent, an adhesive, a thickener, a binder, and a surfactant.

8. The signal protein-containing composition according to claim 1, wherein the composition further comprises other plant growth-promoting rhizobacteria and nematophagus fungi.

9. Use of a signal protein-containing composition according to any one of claims 1, 2, 3 or 5 to 8 for controlling root-knot nematodes and for promoting growth vigor of vegetable crops.