Application and method of methyl selenocysteine in improving insect resistance of rice

Abstract

The invention provides application of methyl selenocysteine in improving insect resistance of rice and a method, belongs to the technical field of agricultural plant protection, and particularly relates to application of methyl selenocysteine in treating rice in a root irrigation or stem and leaf spraying mode. During root irrigation, the concentration of the methyl selenocysteine is 2-10 [mu] M; when the stem leaves are sprayed, the concentration of the methyl selenocysteine is 20-100 [mu] M; the invention discloses that methyl selenocysteine has an excellent prevention and control effect on main piercing-sucking type pests, namely brown planthopper and sogatella furcifera, on rice for the first time, the survival rate of rice planthopper nymphs can be reduced to 10% or below, and the methyl selenocysteine has very high economic benefits.

Description

Technical Field

[0001] This invention relates to the field of agricultural plant protection technology, and more specifically, to the application and method of methylselenocysteine ​​in improving the insect resistance of rice. Background Technology

[0002] Rice planthoppers, especially brown planthoppers ( Nilaparvata lugens ) and white-backed planthopper ( Sogatella furcifera Rice planthoppers (Phytophyta pratibarii) are among the most devastating migratory pests in major rice-growing areas of my country and Asia. They directly damage rice plants by sucking their sap and transmit viral diseases. Currently, agricultural production still relies excessively on chemical pesticides for the control of rice planthoppers. However, this control model has led to a serious "3R" problem: increasing pest resistance, pesticide residues harming the ecological environment and food safety, and frequent pest resurgences. Therefore, developing efficient, environmentally friendly, and sustainable green control technologies has become an urgent need for current agricultural production. Activating the plant's own immune system using chemical elicitors (i.e., inducing insect resistance) is a promising green control strategy. This technology has advantages such as being environmentally friendly, having a long-lasting effect, and being less likely to induce pest resistance. Among these, the jasmonic acid signaling pathway is a key defense mechanism mediating plant resistance against piercing-sucking pests. Currently, although some chemical excitons (such as salicylic acid, methyl jasmonate, and p-fluorophenoxyacetic acid) have been reported, they often have problems such as unstable effects, high costs, or unclear specific mechanisms of action in practical applications, which limit their large-scale promotion and application.

[0003] Methylselenocysteine ​​is a naturally occurring organoselenium compound known in the medical and nutritional fields as a highly effective selenium supplement with potential anticancer activity. In agriculture, it is primarily studied as a selenium fertilizer to increase the selenium content of crops. However, to date, no published literature or patents have reported that methylselenocysteine ​​can be used as a plant-induced insecticide, particularly for inducing systemic resistance in rice against rice planthoppers. This technological gap is precisely what this invention aims to fill. Summary of the Invention

[0004] In order to overcome the above-mentioned defects and deficiencies in the prior art, the present invention provides an application and method of methylselenocysteine ​​in improving the insect resistance of rice.

[0005] To solve the above technical problems: The first objective of this invention is to provide an application of methylselenocysteine ​​in improving the insect resistance of rice.

[0006] Furthermore, methylselenocysteine ​​was treated in rice through root irrigation or foliar spraying.

[0007] Furthermore, during root irrigation, the concentration of the methylselenocysteine ​​is 2μM-10μM.

[0008] Furthermore, when spraying the stems and leaves, the concentration of the methylselenocysteine ​​is 20 μM-100 μM.

[0009] The second objective of this invention is to provide a method for improving the insect resistance of rice using methylselenocysteine, wherein methylselenocysteine ​​is prepared into a solution of a certain concentration and then applied to the roots of the rice or sprayed on the stems and leaves.

[0010] Furthermore, during root irrigation, the concentration of the methylselenocysteine ​​is 2μM-10μM.

[0011] Furthermore, when spraying the stems and leaves, the concentration of the methylselenocysteine ​​is 20 μM-100 μM.

[0012] The beneficial technical effects achieved by this invention are as follows: This invention provides an application and method of methyl selenocysteine ​​in improving the insect resistance of rice. It reveals for the first time that methyl selenocysteine ​​has an excellent control effect on the main piercing-sucking pests on rice, namely brown planthopper and white-backed planthopper, and can reduce the survival rate of rice planthopper nymphs to less than 10%, which has high economic benefits. Attached Figure Description

[0013] Figure 1 This invention illustrates the effect of root irrigation treatment with different concentrations of methylselenocysteine ​​on the survival rate of brown planthopper and white-backed planthopper nymphs in rice, wherein 1A represents brown planthopper and 1B represents white-backed planthopper. Figure 2 The images show the survival of brown planthopper and white-backed planthopper nymphs in rice 5 days after root irrigation treatment with different concentrations of methylselenocysteine, according to an embodiment of the present invention. In the images, 2A represents brown planthopper and 2B represents white-backed planthopper. Figure 3 This invention illustrates the effect of root irrigation treatment with different concentrations of methylselenocysteine ​​on the survival rate of female adult brown planthoppers and white-backed planthoppers in rice, where 3A represents brown planthopper and 3B represents white-backed planthopper. Figure 4 The following are images showing the survival of adult brown planthoppers and white-backed planthoppers in rice after 5 days of root irrigation treatment with different concentrations of methyl selenocysteine, according to an embodiment of the present invention. In the image, 4A represents brown planthoppers and 4B represents white-backed planthoppers. Figure 5 This invention illustrates the effect of different concentrations of methylselenocysteine ​​foliar spray on the survival rate of brown planthopper and white-backed planthopper nymphs in rice, where 5A represents brown planthopper and 5B represents white-backed planthopper. Figure 6The following are images showing the survival of adult brown planthoppers and white-backed planthoppers in rice after 5 days of stem and leaf spraying with different concentrations of methyl selenocysteine, according to an embodiment of the present invention. In the image, 6A represents brown planthoppers and 6B represents white-backed planthoppers. Figure 7 This invention illustrates the effects of different concentrations of methylselenocysteine ​​foliar spraying on the survival rate of female adult brown planthoppers and white-backed planthoppers in rice. 7A represents brown planthopper, and 7B represents white-backed planthopper. Figure 8 The images show the survival of adult brown planthoppers and white-backed planthoppers in rice after 5 days of stem and leaf spraying with different concentrations of methyl selenocysteine, according to an embodiment of the present invention. In this image, 8A represents brown planthoppers and 8B represents white-backed planthoppers. Figure 9 This is a statistical analysis of the jasmonic acid content in rice plants after treatment with methylselenocysteine, as described in an embodiment of the present invention. Detailed Implementation

[0014] The present invention will be further described below with reference to specific embodiments. These embodiments are only used to more clearly illustrate the technical solutions of the present invention and should not be construed as limiting the scope of protection of the present invention.

[0015] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0016] Example 1: Root irrigation treatment with methylselenocysteine ​​improves rice's insect resistance. 1. Reducing nymph survival rate: Methylselenocysteine ​​was added to rice nutrient solution at concentrations of 2 μM, 5 μM, and 10 μM. The control group received nutrient solution without methylselenocysteine. Rice was grown in nutrient solution as single plants. Twenty-four hours after treatment, a specially designed glass cover (4 cm in diameter, 8 cm high, with 48 evenly distributed 0.8 mm diameter holes) was placed over each rice stem. Thirteen newly hatched brown planthopper or white-backed planthopper nymphs were then introduced into the cover. The top of the glass cover was sealed with a circular sponge. The experiment was conducted in an artificial climate chamber at 28±2℃, 70-80% humidity, and 14 hours of light. The number of surviving nymphs of both planthopper species was recorded daily, and each treatment was repeated seven times.

[0017] The results are as follows Figure 1 and Figure 2As shown, starting from the second day after treatment with methylselenocysteine, the survival rate of nymphs in both planthopper species significantly decreased. Specifically, after 7 days of treatment with 2 μM, the survival rate of brown planthopper nymphs was 62.63%, and after 7 days of treatment with 5 μM, the survival rate was 38.46%, both significantly lower than the control survival rate of 86.81%. After 7 days of treatment with 10 μM, the survival rate further decreased to 0, with almost all nymphs dying. After 7 days of treatment with 2 μM, the survival rate of white-backed planthopper nymphs was 49.45%, and after 7 days of treatment with 5 μM, the survival rate was 25.27%, both significantly lower than the control survival rate of 85.71%. After 7 days of treatment with 10 μM, the survival rate further decreased to 1.09%. Therefore, treating rice through irrigation, allowing the rice roots to absorb methylselenocysteine, can significantly improve the direct resistance of rice to rice planthopper nymphs.

[0018] 2. Reducing the survival rate of female adults: Methylselenocysteine ​​was added to the rice nutrient solution to concentrations of 2 μM, 5 μM, and 10 μM. The control group received nutrient solution without methylselenocysteine. The rice was grown in nutrient solution as single plants. Twenty-four hours after treatment, a specially made glass cover (4 cm in diameter, 8 cm high, with 48 evenly distributed 0.8 mm diameter holes) was placed over each rice stem. Thirteen newly emerged female brown planthoppers or white-backed planthoppers were then introduced into the cover. The top of the glass cover was sealed with a circular sponge. The experiment was conducted in an artificial climate chamber at 28±2℃, 70-80% humidity, and 14 hours of light. The number of surviving female adults of both planthopper species was recorded daily, and each treatment was repeated seven times.

[0019] The results are as follows Figure 3 and Figure 4 As shown, starting from the second day after treatment with methylselenocysteine, the survival rate of female adults in both planthopper species significantly decreased. Specifically, after 5 days of treatment with 2 μM, the survival rate of female adults in the brown planthopper was 62.64%, which was not significantly different from the control. After 5 days of treatment with 5 μM, the survival rate of the brown planthopper was 40.66%, significantly lower than the control survival rate of 74.72%, and after 5 days of treatment with 10 μM, the survival rate further decreased to 10.99%. After 5 days of treatment with 2 μM, the survival rate of female adults in the white-backed planthopper was 49.45%, and after 7 days of treatment with 5 μM, the survival rate was 41.76%, both significantly lower than the control survival rate of 75.82%, and after 5 days of treatment with 10 μM, the survival rate further decreased to 12.09%. Therefore, root absorption treatment with methylselenocysteine ​​significantly improved the direct resistance of rice to female adults of the rice planthopper.

[0020] Example 2: Methylselenocysteine ​​foliar spray treatment improves rice's insect resistance. 1. Reducing nymph survival rate: Methylselenocysteine ​​was added and diluted to concentrations of 20 μM, 50 μM, and 100 μM. The control group consisted of water without added methylselenocysteine. Rice was grown in a nutrient solution and planted individually. The rice stems and leaves were sprayed with a small sprayer. After the droplets on the rice stems and leaves had completely dried, a glass cover was placed over the rice stem as described in Example 1, and 13 newly hatched brown planthopper or white-backed planthopper nymphs were introduced. The top of the glass cover was sealed with a circular sponge. The rice was placed in an artificial climate chamber at a temperature of 28±2℃, humidity of 70-80%, and light exposure of 14 hours. The survival rate of the two planthopper nymphs was recorded daily, and each treatment was repeated 7 times.

[0021] The results are as follows Figure 5 and Figure 6 As shown, from the second day after treatment with methylselenocysteine, the survival rate of nymphs of both planthopper species significantly decreased. Specifically, after 7 days of treatment with 20 μM, the survival rate of brown planthopper nymphs was 62.64%, and after 7 days of treatment with 50 μM, the survival rate was 40.66%, both significantly lower than the control survival rate of 86.81%. After 7 days of treatment with 100 μM, the survival rate further decreased to 13.19%. After 7 days of treatment with 20 μM, the survival rate of white-backed planthopper nymphs was 56.04%, and after 7 days of treatment with 50 μM, the survival rate was 39.56%, both significantly lower than the control survival rate of 90.11%. After 7 days of treatment with 100 μM, the survival rate further decreased to 12.08%. Therefore, foliar spraying with methylselenocysteine ​​significantly improved the direct resistance of rice to rice planthopper nymphs.

[0022] 2. Reducing the survival rate of female adults: Methylselenocysteine ​​was added and diluted to concentrations of 20 μM, 50 μM, and 100 μM. The control group consisted of water without added methylselenocysteine. Rice was grown in a nutrient solution and planted individually. The rice stems and leaves were sprayed with a small sprayer. After the droplets on the rice stems and leaves had completely dried, a glass cover was placed over the rice stem as described in Example 1, and 13 newly emerged female brown planthoppers or white-backed planthoppers were introduced. The top of the glass cover was sealed with a round sponge. The rice was placed in an artificial climate chamber at a temperature of 28±2℃, humidity of 70-80%, and light exposure of 14 hours. The number of surviving female adults of both planthopper species was recorded daily, and each treatment was repeated 7 times.

[0023] The results are as follows Figure 7 and Figure 8As shown, from the third day after treatment with methylselenocysteine, the survival rate of adult plantshoppers in both species significantly decreased. Specifically, after 5 days of treatment with 20 μM, the survival rate of adult brown planthoppers was 51.54%, and after 5 days of treatment with 50 μM, the survival rate was 34.07%, significantly lower than the control survival rate of 79.12%. After 5 days of treatment with 100 μM, the survival rate further decreased to 10.99%. After 5 days of treatment with 20 μM, the survival rate of adult white-backed planthoppers was 59.05%, and after 7 days of treatment with 50 μM, the survival rate was 39.56%, both significantly lower than the control survival rate of 78.14%. After 5 days of treatment with 100 μM, the survival rate further decreased to 21.99%. Therefore, foliar spraying with methylselenocysteine ​​significantly improved the direct resistance of rice to adult female planthoppers.

[0024] Example 3: Experiment on increasing jasmonic acid content in rice by treatment with methylselenocysteine Jasmonic acid, a signaling molecule in plants, plays an important role in induced plant resistance. Its level can control the production of plant defense substances. In this example, the concentration of methylselenocysteine ​​used was 10 μM, and the treatment method was the same as in Example 1. The jasmonic acid content in the plants was detected. Specifically, 100 mg of the treated rice stems was ground in liquid nitrogen, and 1 mL of ethyl acetate containing the internal standard d2-JA was precisely added for extraction by shaking. After centrifugation at 12,000 rpm at 4°C, the supernatant was collected, concentrated, and quantitatively analyzed using liquid chromatography-tandem mass spectrometry (LC-MS / MS). The results showed that... Figure 9 As shown, treatment with methylselenocysteine ​​significantly increased the content of endogenous jasmonic acid in rice. After 3 hours of treatment, the jasmonic acid content was 2.48 times that of the control; after 8 hours, it was 5.10 times; and after 24 hours, it was 4.75 times. This indicates that methylselenocysteine ​​can induce the expression of jasmonic acid in rice, thereby initiating its insect-resistant effect.

[0025] The present invention has been disclosed above with reference to preferred embodiments, but it is not intended to limit the present invention. All technical solutions obtained by adopting equivalent substitutions or equivalent transformations fall within the protection scope of the present invention.

Claims

1. Application of methylselenocysteine ​​in improving insect resistance in rice.

2. The application according to claim 1, characterized in that: Rice was treated with methylselenocysteine ​​via root irrigation or foliar spraying.

3. The application according to claim 2, characterized in that: When irrigating the roots, the concentration of the methylselenocysteine ​​is 2μM-10μM.

4. The application according to claim 2, characterized in that: When spraying the stems and leaves, the concentration of the methylselenocysteine ​​is 20 μM-100 μM.

5. A method for improving insect resistance in rice using methylselenocysteine, characterized in that: Prepare a solution of methylselenocysteine ​​at a certain concentration, and then irrigate the rice roots or spray the stems and leaves.

6. The method according to claim 5, characterized in that: When irrigating the roots, the concentration of the methylselenocysteine ​​is 2μM-10μM.

7. The method according to claim 5, characterized in that: When spraying the stems and leaves, the concentration of the methylselenocysteine ​​is 20 μM-100 μM.

Images