CN113678837A

CN113678837A - Plant extract slow-release insect-resist agent and preparation method thereof

Info

Publication number: CN113678837A
Application number: CN202110965975.8A
Authority: CN
Inventors: 王文明
Original assignee: Individual
Current assignee: Individual
Priority date: 2021-08-23
Filing date: 2021-08-23
Publication date: 2021-11-23
Anticipated expiration: 2041-08-23
Also published as: CN113678837B

Abstract

The application relates to a plant extract slow-release insect-resist agent and a preparation method thereof. The application discovers for the first time that Astini in the aster root extract has an insect prevention effect and can be used for preventing insects of gramineae plants, particularly rice. In order to enhance the insect-proof effect, the slow-release insect-proof agent is prepared by dispersing the insect-proof agent in degradable polymer polylactic acid-glycolic acid copolymer (75: 25). The slow-release insect-resist agent is suspended in tap water and sprayed on the surface of a plant, and the slow-release insect-resist agent powder particles containing Astini are adhered to the surface of the plant to slowly release the insect-resist agent, so that the long-term insect-resist effect is achieved. The effect covers the entire growth cycle of the plant.

Description

Plant extract slow-release insect-resist agent and preparation method thereof

Technical Field

The application belongs to the field of insect-resist agents, and particularly relates to a plant extract slow-release insect-resist agent for rice and a preparation method and application thereof.

Background

Rice is the crop with the largest eating population and the longest history in the world. The world rice production is mainly concentrated in Asian regions, wherein China is the second country of the world rice sowing area and the first country of the world rice production. The prevention and control of rice diseases and insect pests are important for capturing the high yield of rice. The damage of plant diseases and insect pests to the growth of rice is always a very important problem which is paid much attention to and solved by farmers.

The pesticide spraying is a main means for preventing insects of crops, people spray the pesticide by stages for a long time, and the pesticide has high toxicity and emits odor, so that the pesticide needs to be blended according to the amount and the proportion in each spraying process, and the odor and the omission of pesticide liquid can enter human bodies at any time when the pesticide is blended and sprayed, thereby forming a great threat to the health of people.

With the continuous enhancement of health concept of people, the demand of people on green food is continuously increased, and novel pesticide insect prevention and disease resistance means and novel materials attract high attention of people. In recent years, there are also a lot of scholars who take targeted control measures for different types of diseases and insect pests, and combine with novel pesticide insect-prevention and disease-resistance measures to perform agricultural control in batches to reduce the incidence of diseases and insect pests.

Aster (academic name: Aster tataricus L.f.), alias: radix asteris, purple wonder, braid and the like; aster genus of Compositae family, perennial herb, with obliquely rising rhizome. The stem is upright, the height is 40-50 cm, the stem is thick and strong, the base part has fibrous dead leaf fragments and often has adventitious roots, ridges and furrows, the stem is thinned and coarse, and the stem has thinned leaves. Basal leaves wither and fall during flowering, and are in the shape of a long round or an oval spoon, with the lower half gradually narrowing into a long handle.

A series of Cyclic peptides are extracted from roots of Aster in 1994 by Hiroshi MOITA and the like, named Astins, and concretely reported are Astin I (Hiroshi MOITA, Shinji NAGASHIM, Koichi TAKEYA, and Hideji ITO KA WA, A Novel Cyclic peptide with a 13-Hydroxy-Y-chloropropine from Aster tarricus, CHEMISTRY LETTERS, pp.2009-2010,1994).

Hiroshi MORTA et al report that Astin I has a beta-hydroxy-gamma-chloroproline residue, and report in detail the isolation procedure and structure confirmation procedure of Astin I. Finally, it was reported that Astin I may have potential anti-tumor activity, but it is not further detailed.

According to the above-mentioned reference provided by Hiroshi MORITA et al, Astin I has a melting point of 174.1-176.5 ℃. The separation process is as follows:

1-butanol soluble fraction of methanol extract of Aster with significant antitumor activity (sarcoma 180A) was separated by HP-20 (a separation column) and silica gel column chromatography. The resulting material was further separated by reverse MPLC or HPLC to give a novel cyclic pentapeptide designated Astin I (1: 0.00015%).

Astin I has the following chemical structure:

the prior art does not give any other use of Astin I.

Disclosure of Invention

In the research process of aster extract, the applicant accidentally notices that Astin I has a certain insect prevention effect, has obvious prevention and control effects on gramineous crops, particularly pests of rice, rice planthopper, rice leaf roller, chilo suppressalis, tryporyza incertulas, rice thrips and the like, and particularly has obvious insecticidal prevention and control effects on chilo suppressalis. The applicant further prepared a slow-release insect repellent containing Astin I for the control of the above gramineous pests. The slow-release insect-resist agent comprises Astin I, polylactic acid-glycolic acid copolymer (75:25) as a slow-release component, sodium dodecyl sulfate as a surfactant and povidone K30 as a binder. The application further provides a preparation process of the slow-release insect repellent, which comprises the following steps:

step 1, dissolving polylactic acid-glycolic acid copolymer (75:25), sodium dodecyl sulfate and povidone K30 in a proper amount of N-methyl pyrrolidone;

step 2, dissolving Astin I in the solution obtained in the step 1;

and 3, taking the solution obtained in the step 2, and carrying out spray drying to obtain medicinal powder containing the Astin I, namely the slow-release insect-resist agent.

In the above-mentioned sustained-release insect repellent, the polylactic acid-glycolic acid copolymer (75:25) as the sustained-release component may be other polylactic acid-glycolic acid copolymers insoluble in water or in other component ratios, such as polylactic acid-glycolic acid copolymer (50: 50).

In the slow-release insect-resist agent, the mass ratio of the Astin to the polylactic acid-glycolic acid copolymer (75:25) is 1: 10-1000.

When the slow-release insect-resist agent is applied, water is added to dilute the slow-release insect-resist agent into a suspension, and then the suspension is sprayed on the surface of crops.

In the slow-release insect-resist agent, sodium dodecyl sulfate is used as a surfactant for reducing the surface tension of a medicine suspension and the surface tension of a plant when a pesticide is applied.

Among the above slow-release insect repellents, povidone K30 is used as a thickener to increase the viscosity of the drug suspension, thereby making the drug suspension more likely to adhere to the surface of crops.

The present application further provides a method for applying the slow-release insect repellent in gramineous plants (rice), comprising: the slow-release insect repellent powder is dispersed in tap water according to the mass percent of 0.1 percent, and 50L of the slow-release insect repellent powder is sprayed on the leaf surfaces of plants per mu.

After the moisture is volatilized, the slow-release insect-resist agent is adhered to the surface of a plant, and along with the natural degradation of the polylactic acid-glycolic acid copolymer (75:25), the Astin I is continuously released, so that the continuous and remarkable insect-resist effect is achieved.

In order to achieve the best insect prevention effect, the pesticide is preferably sprayed once at the tillering stage and the opening stage of the rice respectively. Can play a good role in preventing insects in the whole process of plant growth.

The beneficial effect of this application is as follows:

the application discovers for the first time that Astin I in the aster root extract has an insect prevention effect and can be used for preventing insects of gramineous plants, particularly rice. In order to enhance the insect-proof effect, the slow-release insect-proof agent is prepared by dispersing the insect-proof agent in degradable polymer polylactic acid-glycolic acid copolymer (75: 25). The slow-release insect-resist agent is suspended in tap water and sprayed on the surface of a plant, and the slow-release insect-resist agent powder particles containing the Astin I are adhered to the surface of the plant to slowly release the insect-resist agent, so that the long-term insect-resist effect is achieved. The insect prevention effect can cover the whole growth period of the plants.

The technical effects of the present application are further illustrated by the following experiments:

experiment 1 insecticidal control effect of Astin I water solutions with different concentrations on Chilo suppressalis in rice field

Selecting paddy fields with serious Chilo suppressalis insect pests, spraying aqueous solutions with different concentrations of Astin I (spraying tap water to a blank control group) in groups according to a schematic diagram of figure 1, spraying 50L/mu (50 ml/mu of Astin I aqueous solution) of each medicinal solution with the area of about 4 square meters, and observing the prevention and control effects of the Chilo suppressalis after spraying, wherein the results are shown in the following table.

Drug concentration	Locust number before application	Locust number	1 day after application	Locust number	1 week after application
						Blank control group	111	110	102
0.1％	101	25	23
				0.5％	107	26	24
1.0％	103	21	15
				2.0％	107	8	5
5.0％	110	5	2

。

As can be seen from the data in the table above, compared with the blank control group, the 0.1% -5% Astin aqueous solution has a certain control effect on chilo suppressalis in the rice field, the control effect of the Astin aqueous solution is increased along with the increase of the concentration and the increase of the concentration along with the extension of time, and the fact that the Astin aqueous solution has a certain slow release effect and has the potential of being prepared into slow release medicines is shown.

Drawings

FIG. 1: schematic diagram of prevention and control application of Astin I aqueous solutions with different concentrations to chilo suppressalis in rice

The specific implementation mode is as follows:

example 1 preparation of sustained Release insect repellent containing Astin I

The preparation method comprises the following steps:

step 1, dissolving a prescription amount of polylactic acid-glycolic acid copolymer (75:25), sodium dodecyl sulfate and povidone K30 in a proper amount of N-methyl pyrrolidone;

step 2, dissolving the prescribed quantity Astin I in the solution obtained in the step 1;

Example 2 Slow-release insect repellent agent containing Astin I applied to rice field for preventing striped rice borer insect pest in the comparative example and example of the patent, the field efficacy test is carried out in the red soil paddy field, and the area of each interval is 100m²Random areaAnd (3) group arrangement, wherein each interval is isolated by a plastic film during spraying, and each interval adopts safety utilization measures such as agricultural regulation and control.

(1) Comparative example 1: the commercial 20% dinotefuran water dispersible granules (Hebei bipolar chemical industry Co., Ltd.) are used as rice insect-resist agents (uniformly sprayed according to the amount of 50L/mu (equivalent to 50 g/mu)).

(2) The investigation method comprises the following steps:

before application, 7d, 14d and 30d after application were investigated.

A5-point sampling method is adopted, 5 points are randomly selected in each interval, and each point investigates 5 rice plants in 25 clusters. The specific investigation method comprises the following steps: and (3) cutting off the plants which are subjected to the chilo suppressalis harm in the investigation point from the root flush with the ground, stripping out the residual insects, and recording the total number, the number of live insects and the number of dead insects in the plants to be investigated for calculating the insecticidal effect.

(3) In the experimental process, the field management mode is carried out according to a conventional management mode. The rice slow-release insect-resist agent and the comparative example 1 are applied under windless and rainless sunny weather, the rice insect-resist agent is uniformly sprayed on the surfaces of rice leaves according to the amount of 50L/mu (which is converted into 150 g/mu of the comparative example and 50 g/mu of the insect-resist agent in the embodiment) in the tillering stage and the opening stage of the rice, the time period that the rice leaves are provided with water is avoided during spraying, and if raining occurs within four hours after spraying, re-spraying is needed.

And the water spray was used as a blank control group to evaluate the insecticidal effect after 7 days, 14 days and 30 days of application.

(4) In the tillering stage of rice, the average larva quantity of the chilo suppressalis is about 550 pieces/hundred clumps. The sustained-release insect-resist agents obtained in formulations 1 to 5 of example 1 and the insecticide of comparative example 1 were sprayed at a dose of 50L/mu, respectively, and were sprayed with tap water as a blank control group to evaluate the insecticidal effects 7 days, 14 days and 30 days after the application, and the results are shown in Table 1.

(5) In the break period of rice, the average larva quantity of the chilo suppressalis is about 600 pieces/hundred clumps. The sustained-release insect-resist agents obtained in formulations 1 to 5 of example 1 and the insecticide of comparative example 1 were sprayed at a dose of 50L/mu, respectively, and were sprayed with tap water as a blank control group to evaluate the insecticidal effects 7 days, 14 days and 30 days after the application, and the results are shown in Table 1. The insecticidal effect (%) (reduction rate of population in the administration treatment area-reduction rate of population in the blank control area)/(reduction rate of population in the 100-blank control area) × 100.

TABLE 1 insecticidal Effect (%) of the Slow-Release insect-repellent agent against Chilo suppressalis

Description of the drawings: because dinotefuran is a widely applied pesticide, pests in certain regions have certain drug resistance, and the insecticidal effect of dinotefuran on striped rice borers in paddy fields in different regions is different, so that the dinotefuran is a normal phenomenon. Dinotefuran is used as a positive control drug, and is intended to illustrate the insecticidal and control effects of the slow-release insect-resist agent.

As shown in the data of the above table, the slow release insect repellent containing Astin I prepared according to the formulations 1 to 5 of example 1 has good insecticidal control effect on rice stem borer, the effect increases with the increase of the concentration of Astin I, but when the concentration of Astin I in the insect repellent exceeds 2% and reaches 5%, the insecticidal effect is not significantly increased.

Within the time range of 7 days to 30 days after the pesticide is applied, the pesticide has good insecticidal control effect (similar insecticidal effect), and the insecticidal effect of the formula 1 (the concentration of the Astin I is 0.1%) is better than that of the dinotefuran with the conventional dosage. In the blank control group, although no insecticide is added, the water mist has a certain scouring effect on chilo suppressalis, so that the water mist has a trace insecticidal effect.

Example 3 example 1 formulation 1 application in paddy field insect control effect against other pests

A field efficacy test was designed as described in example 2, with an area of 100m per field²The blocks are randomly arranged, each zone is isolated by a plastic film when spraying, and each zone should take safety utilization measures such as agricultural regulation and control in principle.

(2) And (3) investigation:

before application, 7d, 14d and 30d after application were investigated.

A5-point sampling method is adopted, 5 points are randomly selected in each interval, and each point investigates 5 rice plants in 25 clusters. The specific investigation method comprises the following steps: and (3) cutting off the plant with the insect pest in the investigation point from the root flush with the ground, stripping out the residual insect quantity, and recording the total number, the number of live insects and the number of dead insects of each insect pest in the plant to be investigated for calculating the insecticidal effect.

(3) In the experimental process, the field management mode is carried out according to a conventional management mode. The rice slow-release insect-resist agent (formula 1 in example 1) and the rice slow-release insect-resist agent in comparative example 1 are applied in windless and rainless sunny days, the rice insect-resist agent is uniformly sprayed on the surfaces of rice leaves according to the amount of 50L/mu (50 g/mu compared with powder in comparative example 1 and 50 g/mu of insect-resist agent in formula 1 in example 1) in the tillering stage and the breakage stage of the rice, the time period that the rice leaves are watered is avoided during spraying, and if raining occurs within four hours after spraying, re-spraying is needed. And treated with tap water spray as a blank control group, and the insecticidal effect was evaluated for 7 days, 14 days and 30 days after application.

Table 2 example 1 insecticidal Effect (%) -of formulation 1 on rice planthopper, cnaphalocrocis medinalis guenee, tryporyza incertulas, and rice thrips

Description of the drawings: the blank control group and comparative example 1 data in the above table are the overall insecticidal control effect data of four pests. Description of the drawings: because dinotefuran is a widely applied pesticide, pests in certain regions have certain drug resistance, and the insecticidal effect of dinotefuran on striped rice borers in paddy fields in different regions is different, so that the dinotefuran is a normal phenomenon. Dinotefuran is used as a positive control drug, and is intended to illustrate the insecticidal and control effects of the slow-release insect-resist agent.

As can be seen from the data results in the above table, the insect repellent containing Astin I prepared according to the formula 1 in example 1 has good insecticidal control effect on rice planthopper, cnaphalocrocis medinalis, tryporyza incertulas and thrips oryzae, has good insecticidal control effect (similar insecticidal effect) within the time range of 7 days to 30 days after application, and has equivalent or even better insecticidal effect than that of dinotefuran with conventional dosage.

Claims

Use of AstinI for the preparation of a plant insecticide, wherein AstinI has the following chemical structure:
2. use according to claim 1, wherein the plant is a graminaceous plant, preferably rice.
3. The use according to claim 1, wherein the insects are rice planthoppers, rice leaf rollers, chilo suppressalis, tryporyza incertulas, rice thrips.
4. The use of claim 3, wherein the insect is Chilo suppressalis.
5. An insect-resist agent containing Astin I is characterized in that the insect-resist agent is an aqueous solution, and the mass fraction of Astin in the insect-resist agent is 0.1% -5%.
6. An insect-resist agent containing Astini, which is characterized in that the insect-resist agent is a slow-release insect-resist agent.
7. The insect repellent according to claim 6, wherein the Astini is present in an amount of 0.1% to 5%.
8. The insect repellent according to claim 7, further comprising polylactic acid-glycolic acid copolymer (75:25), sodium lauryl sulfate and povidone K30.
9. The insect repellent according to any one of claims 6 to 8, which is prepared by the following method:

step 1, dissolving a prescription amount of polylactic acid-glycolic acid copolymer (75:25), sodium dodecyl sulfate and povidone K30 in a proper amount of N-methyl pyrrolidone;

step 2, dissolving the prescribed amount of Astini in the solution obtained in the step 1;

and 3, taking the solution obtained in the step 2, and carrying out spray drying to obtain medicinal powder containing Astini, namely the slow-release insect-resist agent.
10. The insect repellent according to any one of claims 6 to 9, wherein the insect repellent is applied to a paddy field by spraying 50g of the insect repellent per mu in 50L of water as a suspension onto the surface of a plant.