Method for improving pest resistance of crops

Abstract

The invention discloses a method for improving pest resistance of crops, and belongs to the technical field of agricultural biology.The method comprises the following steps that alpha-linolenic acid is used for seed dressing treatment, 0.5-1 mL of 4-400 mg / L linolenic acid solution is used for seed dressing treatment on every 1 g of dry seeds, the seeds are fully and evenly stirred, and the seeds are sown after being placed in a shade place for 12-24 h. Alpha-linolenic acid is used for seed dressing for the first time to improve the pest resistance of crops, and the germination rate of the seeds is not affected after the seeds are treated by the method; the growth and development of crops are not influenced; and through seed dressing treatment and intensive operation, the operation is simple and easy to implement, the labor is saved, and the dilemma of difficulty in pesticide spraying can be remarkably relieved.

Description

Technical Field

[0001] The invention belongs to the field of agricultural biotechnology, and particularly relates to a method for improving the pest resistance of crops. Background Art

[0002] Rice is an important food crop. There are many types of rice pests, including the common ones such as the Chilo suppressalis, Sesamina inferens, Striped stem borer, Taiwan rice borer, Rice leaf roller, Brown planthopper, and White-backed planthopper. With the exception of the Rice leaf roller, Brown planthopper, and White-backed planthopper, all other pests are borers that hide their damage and are difficult to effectively control. Furthermore, their uneven development leads to overlapping generations of field populations, making it difficult to determine the optimal period for effective control, further increasing the difficulty of control. Rice leaf roller, Brown planthopper, and White-backed planthopper are migratory pests, and the uncertainty of their migration period also makes them difficult to control. This leads to the excessive and excessive use of pesticides, which not only pollutes the environment but also accelerates the formation and development of pest resistance.

[0003] Corn is also an important grain. It also suffers from a variety of pests, including the fall armyworm, corn borer, armyworm, stem borer, and cotton bollworm. These are migratory pests, and the uncertainty of their arrival times makes them difficult to control. This also leads to problems such as excessive use of pesticides and environmental pollution.

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

[0005] China's plant protection policy is "prevention first, integrated control." Improving the effectiveness of "prevention" is one of the key issues facing the plant protection sector. Seed treatment-based pest and disease control technology effectively implements this "prevention first" approach. Furthermore, this technology is easy to operate, offers intensive processing, and offers excellent control effectiveness, making it popular with growers. Furthermore, seed treatment technology largely avoids the problems associated with pesticide spraying, such as low pesticide utilization, large-scale pesticide loss leading to environmental pollution, and poisoning in humans and animals. To effectively control pests in crops like rice and corn, there is an urgent need to develop green, efficient, simplified, and intensive control technologies. Summary of the Invention

[0006] Purpose of the invention: To address the problems of large dosage and low utilization rate of crop chemical agents, the present invention provides a method for improving the ability of crops to resist pests, thereby providing a basis for the development of green, efficient, simplified and intensive crop pest control technology, and effectively reducing the dosage of crop disease and pest control agents.

[0007] Technical solution: In order to achieve the above purpose, the present invention provides a method for improving the pest resistance of crops, which comprises dressing crop seeds with an α-linolenic acid solution, stirring the seeds thoroughly and evenly, and then sowing the seeds.

[0008] The crops are rice, corn, cabbage and the like.

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

[0010] Wherein, 0.5-1 mL of 4-400 mg / L α-linolenic acid solution is used for seed dressing treatment for every 1 g of dry crop seeds.

[0011] Preferably, 1 mL of 4-400 mg / L α-linolenic acid solution is used for seed dressing treatment per 1 g of dry crop seeds.

[0012] After the seed mixing operation is completed, the seeds are placed in a cool place for 12-24 hours before sowing.

[0013] The sowing is to directly sow the seeds into the field by direct seeding, or to first raise the seedlings in a seedling tray and then transplant them.

[0014] Among them, the pests are the striped stem borer, the infernal stem borer, the yellow stem borer, the Taiwan rice borer, the rice leaf roller, the brown planthopper, the white-backed planthopper, the fall armyworm, the corn borer, the armyworm, the cotton bollworm, etc.

[0015] Numerous substances exist in plant defense hormone pathways, but identifying those that can enhance crop resistance to pests requires extensive experimental validation, and the typical screening method involves spraying with pesticides. The α-linolenic acid identified in this study is used for the first time as a seed dressing for crop seeds. This treatment does not affect seed germination or crop growth, yet significantly enhances crop resistance to pests.

[0016] Beneficial effects: Compared with the prior art, the present invention has the following advantages:

[0017] This invention utilizes α-linolenic acid for the first time to enhance crop resistance to pests. Specifically, it uses a specific concentration of α-linolenic acid for seed dressing, significantly improving crop resistance to pests. This treatment method does not affect seed germination or crop growth, significantly enhancing the pest resistance of crops like rice. Furthermore, seed dressing effectively avoids environmental pollution and other issues associated with pesticide spraying. The intensive, easy-to-use, and labor-saving method significantly alleviates the labor-intensive nature of pesticide spraying. α-linolenic acid is also environmentally and human-friendly, effectively avoiding environmental pollution. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 The height of rice seedlings after the seeds of Nanjing 9108 were treated with α-linolenic acid. Different lowercase letters represent significant differences at the P < 0.05 level.

[0019] Figure 2 The height of rice seedlings after α-linolenic acid seed dressing of Shenliangyou No. 1 seeds was observed. Different lowercase letters indicate significant differences at the P<0.05 level.

[0020] Figure 3 The rice seeds were treated with α-linolenic acid to detect the growth of the Chilo suppressalis. Different lowercase letters represent significant differences at the P<0.05 level.

[0021] Figure 4 To determine the hormone content in rice seeds after α-linolenic acid seed dressing treatment;

[0022] Figure 5 The test was for fall armyworm infection after corn seeds were treated with α-linolenic acid.

[0023] Figure 6 These are individuals that survived after the fall armyworm fed on corn plants treated with α-linolenic acid. DETAILED DESCRIPTION

[0024] The present invention will be further described below with reference to the accompanying drawings and examples.

[0025] Unless otherwise specified, the materials and reagents used in the following examples are commercially available. Experimental procedures not specified in the examples were generally performed under conventional conditions or those recommended by the manufacturer. α-linolenic acid is commercially available and can be purchased at will.

[0026] Example 1

[0027] Three concentration gradients of α-linolenic acid solution were set, namely 4 mg / L, 40 mg / L and 400 mg / L. Nanjing 9108 (japonica rice) and Shenliangyou No. 1 (indica rice) were selected for seed treatment. 1 mL of α-linolenic acid solution of different concentrations was used for seed treatment per 1 g of dry seeds (4-400 mg / L). The weighed rice seeds were placed in a plastic bag (a small amount of seeds was used for indoor experiments), and then the α-linolenic acid solution was added. The plastic bag was shaken vigorously for about 5 minutes to mix thoroughly. After placing in a cool place for 24 hours, the seeds were sown in a culture dish covered with absorbent paper to keep them moist. The water treatment was used as the control (CK). After the seed treatment was completed, the germination rate and average germination time were statistically analyzed.

[0028] Germination rate and germination time measurements showed that after Nanjing 9108 seeds were treated with different concentrations of α-linolenic acid, their germination rates and germination times fluctuated slightly compared to the control, but there were no statistically significant differences (Table 1). After Shenliangyou 1 seeds were treated with different concentrations of α-linolenic acid, their germination rates tended to increase, but there was no significant difference compared to the control. Germination time was significantly shorter when treated with 4 mg / L α-linolenic acid, and slightly longer when treated with 40 mg / L and 400 mg / L α-linolenic acid, but there were no statistically significant differences (Table 2).

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

[0030]

[0031] Table 2 Seed germination rate and germination time of Shenliangyou No. 1

[0032]

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

[0034] The above analysis results show that there is no obvious adverse effect on rice seeds after being treated with different concentrations of α-linolenic acid. On the contrary, there is a certain degree of beneficial effect at certain treatment concentrations, including increasing the germination rate and shortening the germination time. However, continuing to increase the concentration of α-linolenic acid will affect seed germination.

[0035] Example 2

[0036] Three concentration gradients of α-linolenic acid solution were set, namely 4 mg / L, 40 mg / L and 400 mg / L. Nanjing 9108 (japonica rice) and Shenliangyou No. 1 (indica rice) were selected for seed treatment. The clean water treatment was used as the control (CK). The seed dressing treatment method was the same as that in Example 1. The seeds after treatment were sown in disposable plastic cups with a volume of 750 mL. Four rice seeds were sown in each cup, and routine management was performed after sowing. The soil for the plastic cups was composed of a mixture of plant growth matrix, vermiculite and perlite in a ratio of 4:3:3 (V / V / V). The height of the rice seedlings in the plastic cups was measured on the 3rd, 6th and 9th days respectively. 20 plants were randomly measured in each group.

[0037] The measurement results showed that after the seeds of Nanjing 9108 were treated with different concentrations of α-linolenic acid, the plant height of the rice seedlings fluctuated at different time points compared with the control. However, the plant height of the rice seedlings after seed dressing was generally higher than that of the control, and some concentrations were even significantly higher than the control ( Figure 1 After Shenliangyou No. 1 seeds were treated with different concentrations of α-linolenic acid, the height of the rice seedlings in the early treatment group was lower than that of the control group. However, as time went on, the height of the rice seedlings in the treatment group gradually caught up with and exceeded that of the control group ( Figure 2 ).

[0038] The above results show that there is no obvious adverse effect on rice seeds after seed dressing with different concentrations of α-linolenic acid. At certain treatment concentrations, the plant height of rice is significantly higher than that of the control.

[0039] Example 3

[0040] Three concentration gradients of α-linolenic acid solution were set, namely 4 mg / L, 40 mg / L and 400 mg / L. Nanjing 9108 (japonica rice) and Shenliangyou No. 1 (indica rice) were selected for seed treatment. The clean water treatment was used as the control (CK). The seed dressing treatment method was the same as that in Example 1. The treated seeds were sown in disposable plastic cups with a capacity of 750 mL. Four rice seeds were sown in each cup, and routine management was performed after sowing. The soil was the same as in Example 2. The rice seedlings in the plastic cups were inoculated with newly hatched larvae of the yellow stem borer on the 30th day after sowing. Ten test insects were inoculated into each cup of rice seedlings, with 6 replicates per group. The number of live insects was checked on the 6th day after inoculation, and the survival rate of the test insects was statistically analyzed.

[0041] Data analysis showed that after Nanjing 9108 and Shenliangyou No. 1 seeds were treated with different concentrations of α-linolenic acid, the survival rate of the Chilo suppressalis gradually decreased with the increase of α-linolenic acid concentration ( Figure 3 The results showed that exogenous application of α-linolenic acid through seed dressing can significantly improve the resistance of rice to the Chilo suppressalis.

[0042] Example 4

[0043] Rice Nanjing 9108 seeds were treated with 400 mg / L α-linolenic acid. The water treatment was used as the control (CK). The seed dressing treatment method was the same as in Example 1. The seeds after seed dressing were sown in disposable plastic cups with a capacity of 750 mL, and 10 rice seeds were sown in each cup. The soil was the same as in Example 2. The aboveground part of the rice was 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 up. The determination method was liquid chromatography-mass spectrometry (HPLC-MS / MS). The chromatography-mass spectrometry data acquisition instrument system mainly includes ultra-high performance liquid chromatography (UPLC, SCIEX product) and tandem mass spectrometry (MS / MS, QTRAP 6500+, SCIEX product). Mobile phase: ultrapure water containing 0.04% acetic acid (phase A), 99.9% acetonitrile (phase B). An Agilent C18 column (100 mm × 2.1 mm, 1.7 μm) was used, the column temperature was 40°C, and the injection volume was 2 μL. Mass spectrometry data were analyzed using the Metware Database (MWDB) database, which was constructed based on standards. Chromatographic peaks of the target compounds were integrated using a triple quadrupole mass spectrometer in multiple reaction monitoring mode, and quantitative analysis was performed using a standard curve.

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

[0045] Example 5

[0046] Corn seeds (Startin 221) were treated with 400 mg / L α-linolenic acid. Water treatment was used as the control (CK). The seed dressing method was the same as in Example 1. After seed dressing, the seeds were sown in disposable plastic cups with a capacity of 750 mL, and 2 seeds were sown in each cup. The soil was the same as in Example 2. On the 30th day after sowing, newly hatched larvae of the fall armyworm were inoculated. Ten newly hatched larvae were inoculated into each cup of seedlings, with 7 replicates per group. On the 6th day after inoculation, the number of live larvae was checked and the survival rate of the test insects was statistically analyzed.

[0047] The results of the stripping test showed that 30 days after the α-linolenic acid seed dressing treatment, the survival rate of the fall armyworm in the treatment group was significantly lower than that in the control group ( Figure 5 ); and the number of surviving test insects on the treated corn plants was generally smaller than that on the control corn plants ( Figure 6 ).

Claims

1. A method for improving the pest resistance of crops, characterized in that: Treat the crop seeds with α-linolenic acid solution, stir thoroughly and then sow.

2. The method for improving the pest resistance of crops according to claim 1, characterized in that: The crop is rice, corn or cabbage.

3. The method for improving the pest resistance of crops according to claim 1, characterized in that: The crops are preferably rice and corn.

4. The method for improving the pest resistance of crops according to claim 1, characterized in that: For every 1g of dry crop seeds, 0.5-1mL of 4-400mg / L α-linolenic acid solution is used for seed dressing treatment.

5. The method for improving the pest resistance of crops according to claim 1, characterized in that: After the seed dressing operation is completed, place in a cool place for 12-24 hours before sowing.

6. The method for improving the pest resistance of crops according to claim 1, characterized in that: The sowing is to directly sow the seeds into the field by direct seeding, or to first raise the seedlings in a seedling tray and then transplant them.

7. The method for improving the pest resistance of crops according to claim 1, characterized in that: The pests are the striped stem borer, the infered stem borer, the yellow stem borer, the Taiwan rice borer, the rice leaf roller, the brown planthopper, the white-backed planthopper, the fall armyworm, the corn borer, the armyworm, and the cotton bollworm.

8. Application of α-linolenic acid in improving crop resistance to pests.

9. The use according to claim 8, characterized in that The crops are rice, corn or cabbage, and the pests are the striped rice borer, the infered stem borer, the yellow rice borer, the Taiwan rice borer, the rice leaf roller, the brown planthopper, the white-backed planthopper, the fall armyworm, the corn borer, the armyworm and the cotton bollworm.

10. The use according to claim 8, characterized in that In the application, 0.5-1 mL of 4-400 mg / L α-linolenic acid solution is used for seed dressing treatment per 1 g of dry crop seeds.

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