A method of increasing the ability of a crop to resist a pest

Abstract

The application discloses a method for improving the pest resistance of crops, and belongs to the field of agricultural biotechnology, and comprises the following steps: seed dressing treatment is carried out by using alpha linolenic acid, 0.5-1 mL of a 4-400 mg / L linolenic acid solution is used for seed dressing treatment per 1 g of dry seeds, uniform stirring is carried out, and sowing is carried out after 12-24 h of placement in a cool place. The application discloses seed dressing treatment by using alpha linolenic acid to improve the pest resistance of crops, the germination rate of seeds is not affected after the method is used, the growth and development of crops are not affected, the resistance of crops to pests can be significantly improved, and through seed dressing treatment, intensive operation, simple operation, saving of labor, and the difficulty of spraying pesticide can be significantly relieved.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of agricultural biotechnology, and particularly relates to a method for improving the resistance of crops to pests. BACKGROUND

[0002] Rice is one of the important food crops. There are many pests on rice, among which the common ones are Chilo suppressalis, Tryporyza incertulas, Tryporyza nephotetica, Tryporyza incertulas, Cnaphalocrocis medinalis, Nilaparvata lugens, and Sogatella furcifera. Except for Cnaphalocrocis medinalis, Nilaparvata lugens, and Sogatella furcifera, all of them are boring pests, which are hidden and difficult to effectively control. In addition, due to their uneven development, the generations of the populations in the field overlap, making it difficult to grasp the effective control period, further increasing the difficulty of control. Cnaphalocrocis medinalis, Nilaparvata lugens, and Sogatella furcifera are migratory pests, and the uncertainty of the migration period also makes them difficult to control. As a result, a large amount of pesticides are used, which not only causes environmental pollution, but also accelerates the formation and development of pest resistance.

[0003] Corn is also one of the important crops. There are many pests on corn, among which the common ones are Spodoptera frugiperda, Ostrinia nubilalis, Peridroma saucia, Tryporyza incertulas, and Helicoverpa armigera. They are all migratory pests, and the uncertainty of the migration period also makes them difficult to control. Similarly, it also leads to a large amount of pesticide use, environmental pollution, and other problems.

[0004] There have been reports on the control of crop pests and diseases by related substances in the plant defense hormone pathway. Methyl jasmonate is an important substance in the plant defense hormone pathway. Patent (publication number CN111436453A, publication date July 24, 2020) discloses a compound insecticide for controlling green plant bugs. The patent is a mixture of chemical pesticides imidacloprid, methyl jasmonate, and alternaria alternata protein, which is used to control green plant bugs. Based on this technology, the amount of chemical pesticides is reduced while the control effect on green plant bugs is not reduced, achieving good social and ecological benefits.

[0005] The principle of plant protection in China is "prevention first and comprehensive control". How to improve the effectiveness of "prevention" is one of the important problems faced by the plant protection field. The pest and disease control technology based on seed treatment well realizes the plant protection principle of "prevention first". Moreover, the technology is simple to operate, intensive, and has excellent control effect, which is welcomed by the majority of growers. In addition, the seed treatment technology largely avoids the problems of low pesticide utilization rate, environmental pollution, and poisoning of humans and animals caused by pesticide spraying. For effective control of pests on crops such as rice and corn, it is urgent to develop green and efficient, simple, and intensive control technologies. SUMMARY

[0006] Invention purposes: In view of the problems of large amount of chemical agents for crops, low utilization rate and the like, the application provides a method for improving the pest resistance of crops, thereby providing a basis for developing green, efficient, simple and intensive crop pest control technology, and effectively reducing the amount of crop pest control agents.

[0007] Technical scheme: In order to achieve the above-mentioned purpose, the method for improving the pest resistance of crops provided by the application is that the crop seeds are treated with an alpha-linolenic acid solution, and then sowed after sufficient stirring.

[0008] Among them, the crops are rice, corn and cabbage, etc.

[0009] Among them, the crops are preferably rice and corn.

[0010] Among them, 0.5-1 mL of 4-400 mg / L alpha-linolenic acid solution is used for seed treatment per 1 g of dry crop seeds.

[0011] As a preferred, 1 mL of 4-400 mg / L alpha-linolenic acid solution is used for seed treatment per 1 g of dry crop seeds.

[0012] Among them, the seed treatment operation is completed, and then sowed after placing in a cool place for 12-24 h.

[0013] Among them, the sowing is that the seeds are directly scattered in the field by direct sowing, or the seeds are first sowed in a seedling tray, and then transplanted.

[0014] Among them, the pests are Chilo suppressalis, Sesamia inferens, Chilo uphalis, Taivan rice borer, rice leaf roller, Nilaparvata lugens, Sogatella furcifera, Spodoptera exigua, Ostrinia nubilalis, Peridroma saucia and cotton bollworm, etc.

[0015] There are many related substances in the plant defense hormone pathway, but it is necessary to prove by a large number of experiments to screen substances that can promote the pest resistance of crops, and the common screening method is the agent spraying method. The alpha-linolenic acid screened by the application is treated on the crop seeds by seed treatment for the first time, and after the treatment, the germination rate of the seeds is not affected, the growth and development of the crops are not affected, and the resistance of the crops to pests can be significantly improved.

[0016] Advantages: Compared with the prior art, the application has the following advantages:

[0017] The application first uses alpha linolenic acid to improve the ability of crops to resist pests, and the specific feature is to use a specific concentration of alpha linolenic acid for seed dressing treatment, thereby significantly improving the ability of crops to resist pests. The method of the application does not affect the germination rate of seeds after treatment; does not affect the growth and development of crops; can significantly improve the resistance of crops such as rice to pests, and through seed dressing treatment, effectively avoids environmental pollution and other problems caused by pesticide spraying, intensive operation, simple operation, saves labor, and can significantly alleviate the difficulty of pesticide spraying. At the same time, alpha linolenic acid is friendly to the environment and human body, effectively avoiding environmental pollution problems. BRIEF DESCRIPTION OF DRAWINGS

[0018] Figure 1 Rice seedling height after alpha linolenic acid seed dressing treatment of Nangjing 9108, different lowercase letters represent significant differences at P<0.05 level;

[0019] Figure 2 Rice seedling height after alpha linolenic acid seed dressing treatment of Shenliangyou 1, different lowercase letters represent significant differences at P<0.05 level;

[0020] Figure 3 Chilo suppressalis bioassay after alpha linolenic acid seed dressing treatment of rice seeds, different lowercase letters represent significant differences at P<0.05 level;

[0021] Figure 4 Hormone content determination after alpha linolenic acid seed dressing treatment of rice seeds;

[0022] Figure 5 Spodoptera exigua bioassay after alpha linolenic acid seed dressing treatment of corn seeds;

[0023] Figure 6 Surviving individuals of Spodoptera exigua feeding on alpha linolenic acid seed dressing treatment corn plants. DETAILED DESCRIPTION

[0024] The application will be further described below in conjunction with the drawings and examples.

[0025] The materials, reagents and the like used in the following examples can be obtained from commercial channels unless otherwise specified. The experimental methods in the examples not marked with specific conditions are usually carried out according to conventional conditions or according to the conditions recommended by the manufacturer. Alpha linolenic acid is commercially available and can be purchased arbitrarily.

[0026] Example 1

[0027] Three concentration gradients of α-linolenic acid solution were set, 4 mg / L, 40 mg / L and 400 mg / L. Nangjing 9108 (japonica rice) and Shenliangyou 1 (indica rice) were selected for seed treatment. 1 mL of different concentrations of α-linolenic acid solution (4-400 mg / L) was used to treat 1 g of dry seeds. The weighed rice seeds were placed in a plastic bag (less amount of seeds for indoor test), then α-linolenic acid solution was added, and the plastic bag was shaken vigorously for about 5 minutes to fully mix. After 24 hours in a cool place, the seeds were sown in a culture dish covered with water-absorbing paper for moisture retention. The control group was treated with water (CK). After seed treatment, the germination rate and average germination time were statistically analyzed.

[0028] The results of germination rate and germination time measurement showed that after seed treatment with different concentrations of α-linolenic acid, the germination rate and germination time of Nangjing 9108 seeds had some fluctuations compared with the control, but there was no significant difference in statistics (Table 1). The germination rate of Shenliangyou 1 seeds treated with different concentrations of α-linolenic acid had a trend of improvement, but there was no significant difference compared with the control. The germination time was significantly shortened compared with the control at 4 mg / L concentration, and there was a certain extension compared with the control at 40 mg / L and 400 mg / L, but there was no significant difference in statistics (Table 2).

[0029] Table 1 Germination rate and germination time of Nangjing 9108 seeds

[0030]

[0031] Table 2 Germination rate and germination time of Shenliangyou 1 seeds

[0032]

[0033] Note: Different lowercase letters represent significant differences at the P < 0.05 level.

[0034] The above analysis results show that after seed treatment with different concentrations of α-linolenic acid, there is no obvious adverse effect, and there is a certain degree of beneficial effect under certain treatment concentrations, including improving germination rate and shortening germination time, but when the concentration of α-linolenic acid is continuously increased, it will affect seed germination.

[0035] Example 2

[0036] Three concentration gradients of α-linolenic acid solution were set, 4 mg / L, 40 mg / L and 400 mg / L. Nangjing 9108 (japonica rice) and Shenliangyou 1 (indica rice) were selected for seed treatment. The water treatment was used as a control (CK). The seed treatment method was the same as that in Example 1. The treated seeds were sown in disposable plastic cups, and the volume of the plastic cup was 750 mL. Four rice seeds were sown in each cup, and the seeds were managed normally after sowing. The soil in the plastic cup was mixed by plant growth medium, vermiculite and perlite at a ratio of 4:3:3 (V / V / V).

[0037] The measurement results show that the rice seedlings of Nangjing 9108 treated by different concentrations of α-linolenic acid seed dressing have certain fluctuations in plant height at different time points compared with the control, but the plant height of the rice seedlings after seed dressing is generally higher than that of the control, and the plant height of the rice seedlings after seed dressing at some concentrations is even significantly higher than that of the control. Figure 1 The height of the rice seedlings of Shenliangyou 1 treated by different concentrations of α-linolenic acid seed dressing is lower than that of the control in the early treatment group, but the height of the rice seedlings in the treatment group gradually catches up with and exceeds that of the control group over time. Figure 2

[0038] The above results show that the rice seeds treated by different concentrations of α-linolenic acid seed dressing have no obvious adverse effects, and the plant height of the rice is significantly higher than that of the control at some treatment concentrations.

[0039] Example 3

[0040] Three concentration gradients of α-linolenic acid solution were set, 4 mg / L, 40 mg / L and 400 mg / L. Nangjing 9108 (japonica rice) and Shenliangyou 1 (indica rice) were selected for seed treatment. The water treatment was used as a control (CK). The seed treatment method was the same as that in Example 1. The treated seeds were sown in disposable plastic cups, and the volume of the plastic cup was 750 mL. Four rice seeds were sown in each cup, and the seeds were managed normally after sowing. The soil in the plastic cup was mixed by plant growth medium, vermiculite and perlite at a ratio of 4:3:3 (V / V / V).

[0041] Data analysis shows that the survival rate of Chilo suppressalis gradually decreases with the increase of the concentration of α-linolenic acid after the seeds of Nangjing 9108 and Shenliangyou 1 are treated by different concentrations of α-linolenic acid seed dressing. Figure 3 The results show that the exogenous application of α-linolenic acid by seed dressing treatment can significantly improve the resistance of rice to Chilo suppressalis.

[0042] Example 4

[0043] ​Rice seeds (Nanjing 9108) were treated with 400 mg / L concentration of a-linolenic acid. Water treatment was used as control (CK). The seed treatment method was the same as Example 1. After the seed treatment was completed, the seeds were sown in disposable plastic cups, and the volume of the plastic cup was 750 mL. Each cup was sown with 10 rice seeds. The soil was the same as Example 2. The above-ground parts of the rice were collected on the 30th day after sowing, and the contents of jasmonic acid (JA) and jasmonic acid-isoleucine (JA-Ile) were determined, respectively. Four biological replicates were set. The determination method was liquid chromatography-mass spectrometry (HPLC-MS / MS). The main instrument system for collecting chromatography-mass spectrometry data included ultra-high performance liquid chromatography (UPLC, SCIEX product) and tandem mass spectrometry (MS / MS, QTRAP 6500+, SCIEX product). The mobile phase was ultrapure water containing 0.04% acetic acid (phase A) and 99.9% acetonitrile (phase B). The Agilent C18 chromatographic column (100 mm x 2.1 mm, 1.7 μm) was used, the column temperature was 40°C, and the injection volume was 2 μL. The data detected by mass spectrometry were analyzed by using the Metware Database (MWDB) database constructed based on standard substances; the chromatographic peaks of the target substances were integrated by using the multiple reaction monitoring mode of the triple quadrupole mass spectrometer, and the quantitative analysis was performed by using the standard curve.

[0044] The determination results showed that the contents of jasmonic acid and jasmonic acid-isoleucine complex in the rice plants treated with a-linolenic acid seed dressing increased significantly 30 days after the treatment, the content of jasmonic acid increased by about 41% compared with the control, and the content of jasmonic acid-isoleucine increased by about 60% ( Figure 4 ). The results showed that the treatment of a-linolenic acid seed dressing could significantly increase the contents of defense hormones (JA and JA-Ile) in the rice plants, thereby improving the resistance of the rice to pests.

[0045] Example 5

[0046] Corn seeds (StaSweet 221) were treated with 400 mg / L concentration of a-linolenic acid. Water treatment was used as control (CK). The seed treatment method was the same as Example 1. After the seed treatment was completed, the seeds were sown in disposable plastic cups, and the volume of the plastic cup was 750 mL. Each cup was sown with 2 seeds. The soil was the same as Example 2. On the 30th day after sowing, Spodoptera exigua newly hatched larvae were introduced. Each cup of seedlings was introduced with 10 newly hatched larvae, and each group had 7 replicates. On the 6th day after the introduction of the pests, the number of live pests was counted, and the survival rate of the pests was statistically analyzed.

[0047] The counting results showed that the survival rate of Spodoptera exigua on the corn plants treated with a-linolenic acid seed dressing was significantly lower than that on the control plants 30 days after the treatment ( Figure 5 ); and the individual pests surviving on the treated corn plants were generally smaller than those on the control corn plants ( Figure 6 ).

Claims

1. A method of increasing the ability of a crop to resist a pest, the method comprising, The crop seeds are treated with the alpha-linolenic acid solution, and then sowed after fully stirring; The crop is rice or corn, and 0.5-1 mL of 4-400 mg / L alpha-linolenic acid solution is used for seed treatment per 1 g of dry crop seeds.

2. The method for increasing the resistance of a crop to pests according to claim 1, characterized in that, The seed treatment is placed in a cool place for 12-24 h before sowing.

3. The method for increasing the resistance of a crop to pests according to claim 1, characterized in that, The sowing is directly sowing the seeds in the field by live sowing, or raising seedlings in a seedling tray first, and then transplanting.

4. The method for increasing the resistance of a crop to pests according to claim 1, characterized in that, The pests are Chilo suppressalis, Sesamia inferens, Tryporyza incertulas, Taivan rice borer, Cnaphalocrocis medinalis, Nilaparvata lugens, Sogatella furcifera, Spodoptera exigua, Ostrinia nubilalis, Peridroma saucia, and Helicoverpa armigera.

5. Application of alpha-linolenic acid in improving the pest resistance of crops; the crop is rice or corn, and 0.5-1 mL of 4-400 mg / L alpha-linolenic acid solution is used for seed treatment per 1 g of dry crop seeds.

6. Use according to claim 5, characterized in that, The pests are Chilo suppressalis, Sesamia inferens, Tryporyza incertulas, Taivan rice borer, Cnaphalocrocis medinalis, Nilaparvata lugens, Sogatella furcifera, Spodoptera exigua, Ostrinia nubilalis, Peridroma saucia, and Helicoverpa armigera.

Images