Nutrient solution and application thereof in prevention and treatment of crop sheath blight

Abstract

The invention provides a nutrient solution and application thereof in prevention and treatment of crop sheath blight, and belongs to the technical field of rice planting. The nutrient solution provided by the invention contains cysteine with a certain concentration, after the nutrient solution is applied to rice in the trefoil stage and cultivated to the whole growth period, the resistance of the rice to sheath blight can be improved, and meanwhile, the content of chlorophyll, soluble sugar, soluble protein, SOD, POD, MDA and CAT in rice plants is remarkably increased. The nutrient solution provided by the invention can effectively solve the problem of poor sheath blight disease resistance of rice under conventional planting conditions, and has a wide application prospect.

Description

Technical Field

[0001] The invention relates to the technical field of rice planting, and in particular to a nutrient solution and application thereof in preventing and treating sheath blight of crops. Background Art

[0002] Rice is one of the most important food crops worldwide, particularly in Asia, where it is a primary source of food. However, rice is often attacked by various diseases during its growth process, among which sheath blight is one of the major diseases affecting rice yield and quality. Sheath blight not only reduces rice yield but also affects rice quality, and in severe cases, can even lead to a complete crop failure.

[0003] Currently, the main methods for controlling sheath blight include chemical and biological control. However, chemical control can easily lead to environmental pollution and pesticide residues, while biological control is often inconsistent in its effectiveness. Furthermore, while methods such as adjusting the ratio of ammoniacal nitrogen to nitrate nitrogen in the rice nutrient solution, adding exogenous amino acids, and adding exogenous organic acids can all have a certain impact on rice growth, existing technologies have not yet provided methods for improving sheath blight resistance in susceptible rice varieties. Summary of the Invention

[0004] In order to solve the above problems, the present application aims to provide a nutrient solution for cultivating rice and its application in improving rice sheath blight resistance and a cultivation method, so as to improve the sheath blight resistance of rice or susceptible rice.

[0005] On the one hand, the present application provides a nutrient solution for preventing and controlling sheath blight of crops, wherein the nutrient solution contains cysteine ​​at a concentration of 0.01 to 5 mmol / L.

[0006] It is understood that the cysteine ​​mentioned in the present application is L-cysteine ​​(L-Cysteine, Cys) in the amino acid, and its molecular formula is C3H7NO2S.

[0007] In one embodiment, the concentration of cysteine ​​in the nutrient solution is 0.05-4 mmol / L, more preferably 0.1-2 mmol / L, for example 0.5-1.5 mmol / L, and for example 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1.0, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2.0 mmol / L.

[0008] In one embodiment, the nutrient solution further comprises at least one inorganic salt containing any one of the following elements: nitrogen, phosphorus, potassium, sodium, calcium, magnesium, manganese, molybdenum, boron, zinc, copper, and iron.

[0009] In one embodiment, the inorganic salt comprises hydrochloride, sulfite, sulfate, nitrate, phosphate, phosphite, pyrophosphate, acetate, borate, methanesulfonate, succinate, fumarate, citrate, gluconate, malate, or an amine salt.

[0010] In one embodiment, the nutrient solution further contains any one or more of the following components:

[0011] NH4Cl, NaNO3, NaH2PO4, K2SO4, CaCl2, MgSO4, MnCl2, Na2MoO4, H3BO4, ZnSO4, CuSO4, EDTA-Na2, FeSO4.

[0012] It is understandable that the above components can be added to the nutrient solution in the amount used for conventional crops or in the amount required.

[0013] On the other hand, the present application provides the use of the nutrient solution for preventing and controlling sheath blight of crops in the preparation of a preparation having any of the following effects:

[0014] (I) improving the resistance of crops or crops susceptible to sheath blight;

[0015] (II) increasing the content of catalase, malondialdehyde, peroxidase, superoxide dismutase, soluble sugar, soluble protein and / or chlorophyll in crops or crop plants susceptible to sheath blight;

[0016] (III) increasing the yield of crops or crops susceptible to sheath blight.

[0017] Among them, chlorophyll includes chlorophyll a and chlorophyll b.

[0018] In one embodiment, the crop is selected from any one of rice, wheat, corn, soybean, cotton, and barley.

[0019] Preferably, the crop is rice.

[0020] More preferably, the crop is rice "Zhonghua No. 11".

[0021] In one embodiment, the nutrient solution is applied starting from the three-leaf stage of the crop until the crop reaches the full growth period.

[0022] In one embodiment, the preparation includes but is not limited to culture medium, pesticides, fertilizers, immune inducers, etc.

[0023] On the other hand, the present application provides a method for preparing the nutrient solution for preventing and controlling sheath blight of crops, comprising:

[0024] Obtaining inorganic salt culture solution for cultivating crops;

[0025] Cysteine ​​is added to the inorganic salt culture solution to prepare a nutrient solution containing cysteine ​​at a concentration of 0.01 to 5 mmol / L.

[0026] On the other hand, the present application provides the use of cysteine ​​in the preparation of a crop cultivation treatment agent having any of the following effects:

[0027] (a) improving the resistance of crops or crops susceptible to sheath blight to sheath blight;

[0028] (b) increasing the content of catalase, malondialdehyde, peroxidase, superoxide dismutase, soluble sugar, soluble protein and / or chlorophyll in crops or crop plants susceptible to sheath blight;

[0029] (c) increasing the yield of crops or crops susceptible to sheath blight.

[0030] Among them, chlorophyll includes chlorophyll a and chlorophyll b.

[0031] In one embodiment, the cultivation treatment agent is selected from any one of culture medium, pesticide, fertilizer, and immune inducer.

[0032] In one embodiment, the concentration of cysteine ​​in the cultivation treatment agent is 0.01-5 mmol / L, preferably 0.05-4 mmol / L, more preferably 0.1-2 mmol / L, for example 0.5-1.5 mmol / L, for example 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1.0, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2.0 mmol / L.

[0033] In another aspect, the present application provides a method for improving crop resistance to sheath blight, the method comprising the following steps:

[0034] The crop seeds are cultured to the three-leaf stage, and the nutrient solution is applied until the crop seeds reach the full growth stage.

[0035] In one embodiment, the application method can be as a culture solution for hydroponics in soilless culture, or as drip irrigation, foliar spraying, etc. in soil culture.

[0036] In another aspect, the present application provides a method for increasing the yield of rice susceptible to sheath blight, the method comprising the following steps:

[0037] The nutrient solution is applied to rice susceptible to sheath blight until the rice is cultivated to the full growth period.

[0038] In one embodiment, the rice is rice variety "Zhonghua No. 11".

[0039] Preferably, the application time is when the rice reaches the three-leaf stage.

[0040] This application has at least the following beneficial effects:

[0041] 1. The nutrient solution provided in this application, by adding an appropriate concentration of cysteine ​​to a conventional nutrient solution and applying it to crops, can effectively improve the plants' resistance to sheath blight. For crops infected with sheath blight pathogens, it can significantly improve the symptoms of the crop plants, does not inhibit the growth and development of the plants, and can help increase the yield of susceptible crops. Experimental results show that the nutrient solution provided in this application has a significant effect on improving rice sheath blight resistance, CAT content, MDA content, POD content, SOD content, soluble sugar content, soluble protein content, and chlorophyll content.

[0042] 2. The method of cultivating rice using the nutrient solution provided in this application can solve the problem of rice yield reduction due to the invasion of rice sheath blight, which also affects the quality of rice and may even lead to total crop failure in severe cases. It is conducive to accelerating the process of breeding rice varieties with resistance to rice sheath blight and promoting the construction of green agriculture. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0044] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for the embodiments or the description of the prior art. For those skilled in the art, other drawings can be obtained based on these drawings without inventive work. In the drawings:

[0045] Figure 1 The following are pictures of the leaf sheath blight phenotypes of "Zhonghua No. 11" after being infected with sheath blight pathogen spores by treating different groups of nutrient solutions in Example 1;

[0046] Figure 2 The pictures are of the phenotype of sheath blight on the stems of "Zhonghua No. 11" after being infected with sheath blight pathogen spores by different groups of nutrient solutions in Example 1;

[0047] Figure 3 The following are plant status diagrams of "Zhonghua No. 11" after being infected with spores of sheath blight pathogen treated with different groups of nutrient solutions in Example 1, wherein A is a plant phenotype diagram, B is a bar graph of plant height results; C is a bar graph of root length results; and D is a bar graph of single plant weight results;

[0048] Figure 4 The following are graphs showing the content of different substances in the plants of "Zhonghua No. 11" after being infected with sheath blight pathogen spores by treating different groups of nutrient solutions in Example 2, wherein A is a histogram of CAT content, B is a histogram of MDA content, C is a histogram of POD content, D is a histogram of SOD content, E is a histogram of soluble sugar content, and F is a histogram of soluble protein content;

[0049] Figure 5 The results of the chlorophyll content in the plants of "Zhonghua No. 11" after being infected with sheath blight pathogen spores by treating different groups of nutrient solutions in Example 3 are shown in Figure 3, wherein A is a bar graph of the total chlorophyll content, B is a bar graph of the chlorophyll a content, and C is a bar graph of the chlorophyll b content;

[0050] Figure 6 This is a graph showing the growth phenotype of rice sheath blight pathogens under the treatment conditions of adding the same and different types of exogenous amino acids to the culture medium after the sheath blight pathogens are cultured in the culture medium in Example 4;

[0051] Figure 7 for Figure 6 Bar graph of the colony diameter results of rice sheath blight pathogen under different types of exogenous amino acid treatment conditions. DETAILED DESCRIPTION

[0052] The present invention is described below by specific embodiments. Unless otherwise specified, the technical means used in the present invention are methods well known to those skilled in the art. In addition, the embodiments are to be understood as illustrative rather than limiting the scope of the present invention. The essence and scope of the present invention are primarily defined by the claims. For those skilled in the art, without departing from the essence and scope of the present invention, various changes or modifications of the material composition and dosage in these embodiments also fall within the scope of the present invention.

[0053] Unless otherwise specified, the materials, reagents, and experimental instruments used in the following examples were all commercially available. The inorganic salts used to prepare the nutrient solution and the 20 amino acids involved were all commercially available. The kits used to detect plant CAT, MDA, POD, SOD, soluble sugars, and soluble proteins were all provided by Suzhou Grace Biotechnology Co., Ltd. The rice sheath blight pathogen used in the experiments was the NBRC30459 standard strain Thanatephorus cucumeris provided by NBRC. Rice sheath blight (Rhizoctonia solani) is commercially available.

[0054] Among them, the "Zhonghua No. 11" in the examples of the present application is a model crop of japonica rice varieties, which has been reported in many existing technical documents, such as: "Ni Pichong. A new rice variety cultivated by flower culture - Zhonghua No. 11 [J]. Crop Variety Resources, 1989, (04): 42.", "Gao Lin, Chen Chunli. Effects of NaCl stress on the root growth and development of rice variety Zhonghua 11 seedlings [J]. Seed, 2012, 31 (07): 7-12.", etc.

[0055] The rice seeds used in subsequent experiments are currently stored in the Plant Hormone and Nutrition Molecular Regulation Laboratory at the Institute of Rice Industry Technology, Guizhou University. The applicants commit to making the aforementioned rice genetic resources available to the public within 20 years of the application date.

[0056] Example 1: Effects of different cysteine ​​concentration treatments on the growth and development of rice variety "Zhonghua No. 11" The specific experimental method is as follows:

[0057] 1. Rice seed soaking: Soak the rice "Zhonghua No. 11" seeds in 0.6% dilute nitric acid for 6 to 8 hours.

[0058] 2. Cultivation of rice seeds: After soaking, rinse the seeds with deionized water 3 to 5 times, divide them into culture dishes, add appropriate amount of purified water, and culture them in an incubator at 37°C. Change the water 1 to 2 times a day.

[0059] 3. Hydroponics: After the seeds germinate, wait until their buds grow to 1-2 cm, sow them in 96-well plates and place them in a 4-L culture box with clean water for culture until the first incomplete leaf appears. Then, change to ordinary rice nutrient solution and culture until the 3-leaf stage. Then, transplant them into a 15-L culture pot. Set up 4 culture pots and add 12 L of ordinary rice nutrient solution to each culture pot. Among them, one culture pot is used as a blank control group that is not infected with sheath blight and is not treated, recorded as CK; one culture pot is used as a 0 mM cysteine ​​treatment group that is infected with sheath blight and is not treated, recorded as 0 mM Cys; one culture pot is used as a treatment group that is infected with sheath blight and added with 1 mM cysteine, recorded as 1 mM Cys; and one culture pot is used as a treatment group that is infected with sheath blight and added with 2 mM cysteine, recorded as 2 mM Cys.

[0060] The common rice nutrient solution may be a commercially available culture solution or a conventional culture solution disclosed in the prior art. In this embodiment, the nitrogen-free common rice nutrient solution formula shown in Table 1 is used (reference: Yoshida S, Fomo DA, Cock JH, et al. Routine procedure for growing rice plants in culture solution. In: Laboratory manual for physiological studies of rice [J]. International Rice Research Institute, 61-66.):

[0061] Table 1 Common rice nutrient solution formula

[0062]

[0063] Prepare cysteine ​​stock solution (all concentrations are 1 mol / L), and use the stock solution to prepare common nutrient solution according to the dosage shown in Table 2.

[0064] The treatment conditions of different groups in step 3 and the specific preparation of the culture medium are shown in Table 2:

[0065] Table 2

[0066]

[0067] Among them, the treatment for infection with sheath blight pathogen is spray inoculation of sheath blight pathogen spores, and the specific steps are as follows:

[0068] (1) The sheath blight pathogen (standard strain NBRC30459) was cultured on PDA medium. After the mycelium grew well, the spores on the mycelium surface were washed with sterile water to prepare a spore suspension;

[0069] (2) Adjust the concentration of spore suspension to an appropriate range (e.g. 10 6 Spores), the spore suspension was placed in a sprayer and sprayed evenly on the leaf surfaces of Zhonghua No. 11 rice plants in different treatment groups simultaneously and in equal amounts to ensure that the leaf surfaces were moistened;

[0070] (3) After spraying, the plants were placed under suitable temperature and humidity conditions of 28°C and relative humidity above 90%, and kept moisturized for 24 hours to promote spore attachment and infection, and an appropriate amount of surfactant was added to enhance the spraying effect.

[0071] After all the "Zhonghua No. 11" rice seedlings in each group have grown to the heading stage, the plant height, fresh weight, root length and disease status of each part of the rice seedlings were counted. The specific steps are as follows: select a heading plant with a plant height close to the average plant height from each group, place the whole plant, leaves and stems on a black cloth and spread them out in a row, and observe their growth status. The results are as follows: Figure 1-3 shown.

[0072] Depend on Figure 1 and Figure 2 The results show that after inoculation with sheath blight pathogen spores, under natural conditions, the leaves and stems of rice plants in the 0mM treatment group showed a susceptible growth state, the leaves and stems of rice plants treated with 2mM cysteine ​​showed a slightly susceptible growth state, and the leaves and stems of rice plants treated with 1mM cysteine ​​showed a non-susceptible growth state, just like the uninfected CK group-treated rice.

[0073] Depend on Figure 3 The results show that compared with the healthy plant CK group, the 0mM Cys group cultured in ordinary nutrient solution and the 1mM Cys group with 1mM cysteine ​​added had slightly lower root length and plant weight after infection with sheath blight pathogens. However, there was no significant growth difference between the 1mM Cys group and the 0mMCys group. This shows that when infected, the 1mM Cys treatment can achieve significant disease resistance while hardly inhibiting the plant height, root length, and fresh weight, thereby helping to increase rice yield in the infected state. The 2mM treatment had no effect on the sheath blight resistance of "Zhonghua No. 11", and the plant height, fresh weight, and root length of rice under this treatment were significantly inhibited.

[0074] The above results indicate that exogenously adding 1 mM cysteine ​​to the ordinary rice nutrient solution can significantly improve the resistance of infected rice to sheath blight, and does not significantly inhibit the growth and development of susceptible plants, which is the optimal treatment method.

[0075] Example 2: Effects of different treatments on the content of disease resistance index substances in "Zhonghua No. 11" rice plants

[0076] The levels of catalase (CAT), malondialdehyde (MDA), superoxide dismutase (SOD), peroxidase (POD), soluble sugar and soluble protein in plants are all physiological indicators for judging the stress resistance of plants during growth.

[0077] In this example, the rice plants cultivated in Example 1 were tested for the content of the above-mentioned indicator substances. The reagents used for the test were CAT kit, MDA kit, SOD kit, POD kit, soluble sugar kit, and soluble protein kit provided by Suzhou Grace Biotechnology Co., Ltd. The test methods were based on the methods provided in the kit instructions. The tissue samples tested were rice leaves. The test results are shown in Figure 2. Figure 4 Shown in AF.

[0078] Depend on Figure 4 The results of AF showed that when cysteine ​​was added to a final concentration of 1mM in a standard rice nutrient solution, the CAT, MDA, SPD, and POD contents of "Zhonghua No. 11" plants were almost the same as those of healthy, uninfected plants, while the soluble sugar and soluble protein contents were higher than those of healthy plants. In contrast, all indicators of the infected 0mM Cys group showed significant decreases compared to healthy plants, while some indicators of the 2mM Cys group improved but did not reach the levels of uninfected plants, and even the soluble sugar and soluble protein contents were lower than those of the infected 0mM Cys group. This indicates that the nutrient solution supplemented with 1mM cysteine ​​can improve rice resistance to sheath blight.

[0079] Example 3: Effect of exogenous application of cysteine ​​on chlorophyll content in rice plants of "Zhonghua No. 11"

[0080] The chlorophyll content in rice leaves is related to the photosynthetic rate and crop growth rate, and can characterize the growth status of rice.

[0081] In this example, the chlorophyll content of the rice plants cultivated in Example 1 was detected. The detection method was based on the literature (Nurkemaier Murati, Yang Yajie, Parhat Abdukerimu, et al. Comparison of methods for determining chlorophyll content in wheat [J]. Jiangsu Agricultural Sciences, 2021, 49(9): 4.), and the tissue sample tested was rice leaves. The test results are as follows: Figure 5 As shown in AC.

[0082] Depend on Figure 5 AC results show that, when cysteine ​​was added to a standard rice nutrient solution to a final concentration of 1mM, the total chlorophyll, chlorophyll a, and chlorophyll b contents of Zhonghua No. 11 were almost identical to those of healthy, uninfected plants. The total chlorophyll and chlorophyll a contents of the infected rice plants in the 0mM Cys group decreased significantly compared to the CK group, while the total chlorophyll, chlorophyll a, and chlorophyll b contents of the rice plants in the 2mM Cys group were lower than those in the 0mM Cys group. This indicates that the 1mM cysteine-treated rice nutrient solution formula can significantly improve the photosynthesis efficiency and growth and development of rice plants infected with sheath blight.

[0083] Example 4: Effects of exogenously applied amino acids on the growth of sheath blight pathogens

[0084] The specific steps are as follows:

[0085] Prepare PDA culture medium for Rhizoctonia solani (standard strain NBRC30459) and add 20 kinds of amino acids to the culture medium to make the final concentration of 40mmol / L. Pour the culture medium into sterile culture dishes. Wait for it to solidify, inoculate Rhizoctonia solani on the culture medium, culture at 28℃ for 24h, observe and measure the diameter of the bacterial ring, and take pictures. The results are as follows: Figure 6 As shown, Figure 6 The statistical data results are shown in the bar chart. Figure 7 .

[0086] Depend on Figure 6 and Figure 7 The results showed that compared with the control and other amino acids, cysteine ​​showed a significant inhibitory effect on the growth of rice sheath blight, while most amino acids promoted the growth of the fungus.

[0087] The foregoing is merely an embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various changes and variations. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present application should all be included within the scope of the claims of the present application.

Claims

1. A nutrient solution for preventing and treating sheath blight of crops, characterized in that: The nutrient solution contains cysteine ​​with a concentration of 0.01 to 5 mmol / L.

2. The nutrient solution according to claim 1, wherein The nutrient solution also includes at least one inorganic salt containing any one of the following elements: nitrogen, phosphorus, potassium, sodium, calcium, magnesium, manganese, molybdenum, boron, zinc, copper, and iron.

3. The nutrient solution according to claim 2, characterized in that The inorganic salt includes hydrochloride, sulfite, sulfate, nitrate, phosphate, phosphite, pyrophosphate, acetate, borate, methanesulfonate, succinate, fumarate, citrate, gluconate, malate or amine salt.

4. Use of the nutrient solution for preventing and controlling sheath blight of crops according to any one of claims 1 to 3 in the preparation of a preparation having any one of the following effects: (I) improving the resistance of crops or crops susceptible to sheath blight to sheath blight; (II) increasing the content of catalase, malondialdehyde, peroxidase, superoxide dismutase, soluble sugar, soluble protein and / or chlorophyll in crops or crop plants susceptible to sheath blight; (III) increasing the yield of crops or crops susceptible to sheath blight.

5. The use according to claim 4, characterized in that The crops are selected from any one or more of rice, wheat, corn, soybean, cotton and barley.

6. The use according to claim 4, characterized in that The nutrient solution is applied starting from the three-leaf stage of the crop until the crop reaches the full growth period.

7. The method for preparing the nutrient solution for preventing and controlling sheath blight of crops according to any one of claims 1 to 3, characterized in that: include: Obtaining inorganic salt culture solution for cultivating crops; Cysteine ​​is added to the inorganic salt culture solution to prepare a nutrient solution containing cysteine ​​at a concentration of 0.01 to 5 mmol / L.

8. Use of cysteine ​​in the preparation of a crop cultivation treatment agent having any of the following effects: (a) improving the resistance of crops or crops susceptible to sheath blight to sheath blight; (b) increasing the content of catalase, malondialdehyde, peroxidase, superoxide dismutase, soluble sugar, soluble protein and / or chlorophyll in crops or crop plants susceptible to sheath blight; (c) increasing the yield of crops or crops susceptible to sheath blight; The concentration of cysteine ​​in the cultivation treatment agent is 0.01 to 5 mmol / L; Preferably, the cultivation treatment agent is selected from any one of culture medium, pesticide, fertilizer, and immune inducer.

9. A method for improving crop resistance to sheath blight, characterized in that: The method comprises the following steps: The crop seeds are cultured to the three-leaf stage, and the nutrient solution according to any one of claims 1 to 3 is applied until the crop seeds reach the full growth stage.

10. A method for increasing the yield of rice susceptible to sheath blight, characterized in that: The method comprises the following steps: Applying the nutrient solution according to any one of claims 1 to 3 to rice susceptible to sheath blight until the rice is cultivated to the full growth period; Preferably, the rice is rice variety Zhonghua No. 11.

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