Application of wild rose roxb. polysaccharide in resisting plant diseases and plant resistance inducer containing wild rose roxb. polysaccharide

Abstract

The present invention provides the application of wild rosehip polysaccharide in resisting plant diseases, and the plant diseases include wheat diseases, rice diseases, tomato diseases and cucumber diseases. The present invention also provides a plant resistance inducer containing wild rosehip polysaccharide. The plant resistance inducer of the present invention can be applied to the above-ground part of the plant by spraying, and the preferred spraying time is before the occurrence of the disease. The concentration of the active ingredient in the spraying solution is 100-300 mg / L, and the spraying amount per plant can be 20-60 mg. It has been verified that after spraying the plant resistance inducer of the present invention on the plant, it can prevent plant diseases, especially wheat scab, wheat powdery mildew, rice sheath blight, tomato gray mold and cucumber downy mildew. The active ingredient of the resistance inducer of the present invention is a plant polysaccharide, and the active ingredient is easy to obtain and is safe and harmless. The plant resistance inducer in the present invention can effectively prevent various diseases of various plants and has wide applicability.

Description

[0001] This invention claims a domestic priority, with the application date being February 13, 2023, the application number being CN2023101049404, and the invention title being "Application of Rosa roxburghii Tratt polysaccharide in anti-plant diseases and plant elicitor containing Rosa roxburghii Tratt polysaccharide".

Technical Field

[0002] This invention belongs to the field of pesticides, specifically relates to the application of Rosa roxburghii Tratt polysaccharide in anti-plant diseases, and also relates to a plant elicitor with Rosa roxburghii Tratt polysaccharide as the active ingredient.

Background Art

[0003] In recent years, the research on plant induced disease resistance has gradually emerged, providing new ideas for the effective control of plant diseases. This method mainly improves the resistance of plants to harmful organisms through physical, chemical, and biological methods, thereby reducing the occurrence of plant diseases. Applying plant induced disease resistance in agriculture can effectively avoid the safety and resistance problems brought by traditional chemical pesticides, greatly reducing the control cost, and being more conducive to popularization in production practice. Currently, many scholars have focused on research related to inducing plant disease resistance. Polysaccharides are one of the rich substance groups in nature. They not only have a wide range of sources and low toxicity, but also have various good biological activities such as antibacterial, antioxidant, and promoting the growth of organisms. They are widely used as plant elicitors, growth regulators, etc. to control various plant diseases and regulate the growth of crops. For example, Li Pengpeng et al. found that lentinan can play a certain elicitor role against cucumber downy mildew; Qiu Chi et al. found that after treating cucumbers with the oligosaccharide extract obtained from kelp 3 times, it can induce cucumbers to produce resistance to downy mildew; Yi Yanjie et al. found that burdock oligosaccharides can induce wheat to produce resistance to powdery mildew to a certain extent. Inducing plants to produce disease resistance as a new method for controlling plant diseases can effectively maintain ecological balance and obtain green agricultural products that meet the needs of the masses. Therefore, strengthening related research undoubtedly has great significance. (Wu Lina, Liu Mei, Li Xinghong. Biological activities of polysaccharides and their applications in vegetables [J]. Vegetables, 2021(05): 32 - 38.; Wang Zhenwei, Zheng Lijing. Research progress on extraction, purification and biological activities of Rosa roxburghii Tratt polysaccharide [J]. Agricultural Technology & Equipment, 2021(11): 105 - 107.; Li Pengpeng. Research on the role of lentinan in inducing cucumber resistance to downy mildew and its synergistic effect with fluopicolide [D]. Shandong Agricultural University, 2014.; Qiu Chi, Li Baoju, Shi Yanxia, etc. Resistance induction of cucumbers to downy mildew by oligosaccharide substances [J]. Chinese Journal of Biological Control, 2005(01): 57 - 59.; Yi Yanjie, Liu Na, Li Cuixiang, etc. Influence of burdock oligosaccharides induction on wheat powdery mildew resistance [J]. Journal of Triticeae Crops, 2009, 29(03): 540 - 542.)

[0004] Wild Rosa roxburghii Tratt is the fruit of Rosa roxburghii Tratt, a deciduous shrub of the genus Rosa in the Rosaceae family. Traditional Chinese medicine often uses the fruit and root of Rosa roxburghii Tratt as medicine, which has high medicinal value in the treatment of digestive system diseases, cardiovascular system diseases and anti-tumor. At present, it has been well applied in the fields of functional foods and pharmaceutical preparations. Wild Rosa roxburghii Tratt polysaccharide is one of the main functional components contained in Wild Rosa roxburghii Tratt, and there are relevant research reports in the medical field. Wild Rosa roxburghii Tratt polysaccharide has certain effects in inhibiting melanoma, antioxidant, anti-fatigue, protecting neural stem cells, etc. For example, Chen Hui et al. found that in vitro, Rosa roxburghii Tratt polysaccharide could inhibit the proliferation of mouse melanoma B16 cells, promote the apoptosis of B16 cells, and showed a dose-dependent manner. In vivo, Rosa roxburghii Tratt polysaccharide could significantly inhibit the growth of tumors. Compared with the control group, the tumors in the treatment group were smaller, and the proportions of CD4+T, CD8+T and NK cells in the spleen of mice in the treatment group were higher, the expression of CD69 on immune cells was higher, and at the same time, the secretion level of IFN-γ in the serum of mice in the treatment group was higher; Cao Jingjing et al. found that Rosa roxburghii Tratt polysaccharide could prolong the weight-bearing swimming time of mice, improve the blood glucose, muscle glycogen, SOD, CAT and GSH contents of free-swimming mice, and reduce the levels of lactic acid, lactate dehydrogenase, creatine kinase and MDA. Therefore, it has further research value in anti-fatigue; Yang Juan et al. found that multiple Rosa roxburghii Tratt polysaccharide components could stimulate PC12 cells to produce neurite-like protrusions, which proved that most Rosa roxburghii Tratt polysaccharide components have neurotrophic activity; Yang Juan et al. found that the damage of neural stem cells in the experimental groups with different concentrations of Rosa roxburghii Tratt polysaccharide was reduced to varying degrees. The mortality rate of neural stem cells and the leakage rate of lactate dehydrogenase in the experimental group with high concentration of Rosa roxburghii Tratt polysaccharide were lower, and there was a significant difference compared with the glutamate damage group. It was thus confirmed that it has an obvious protective effect on neural stem cell damage. (Chen Hui, Chang Ying, Liu Zhenguo. Experimental study on the inhibitory effect of Rosa roxburghii Tratt polysaccharide on mouse melanoma [J]. Shaanxi Medical Journal, 2021, 50(05): 529-533.; Cao Jingjing, Yang Weijie, Cao Yi. Research on the antioxidant and anti-fatigue effects of Rosa roxburghii Tratt polysaccharide [J]. Chinese Journal of Basic Medicine in Traditional Chinese Medicine, 2018, 24(04): 474-476+481.; Yang Juan, Yang Fumei, Sun Qianyun. Isolation, purification and neurotrophic activity of Rosa roxburghii Tratt polysaccharide [J]. Chinese Pharmaceutical Journal, 2006(13): 980-982.; Yang Juan, Chen Fuxue, Liang Guangyi. Protective effect of Rosa roxburghii Tratt polysaccharide on glutamate-induced damage of neural stem cells [J]. Acta Nutrimenta Sinica, 2005(04): 339-341.)

[0005] At present, there is no research on the application of Wild Rosa roxburghii Tratt polysaccharide in the prevention and control of agricultural diseases.

Summary of the Invention

[0006] The purpose of the present invention is to provide a Wild Rosa roxburghii Tratt polysaccharide with uses for plant diseases, and to confirm its application as an active ingredient in the preparation of plant elicitors.

[0007] Based on this, the present invention provides the application of wild rose hip polysaccharide in combating plant diseases, and the plant diseases include wheat diseases, rice diseases, tomato diseases and cucumber diseases.

[0008] In the present invention, the wheat disease is wheat scab or wheat powdery mildew, the rice disease is rice sheath blight, the tomato disease is tomato gray mold, and the cucumber disease is cucumber downy mildew.

[0009] In the present invention, wheat scab is caused by Fusarium graminearum; wheat powdery mildew is caused by Blumeria graminis; rice sheath blight is caused by Rhizoctonia solani: tomato gray mold is caused by Botrytis cinereal; cucumber downy mildew is a plant disease caused by Pseudoperonospora cubensis.

[0010] In the present invention, the average molecular weight of the wild rose hip polysaccharide is 97.58 kDa.

[0011] The wild rose hip polysaccharide of the present invention is a product that can be purchased on the market, such as the products sold by Lanzhou Wateles Biotech Co., Ltd. under the names of "wild rose hip polysaccharide" or "wild rose hip extract", or the products sold by Shaanxi Sinuote Biotechnology Co., Ltd. under the names of "wild rose hip polysaccharide" or "wild rose hip extract".

[0012] Based on this, the present invention also provides a plant resistance inducer, and the plant resistance inducer contains wild rose hip polysaccharide.

[0013] As a preferred embodiment, the plant resistance inducer further contains auxiliaries and adjuvants available in agriculture.

[0014] In a preferred embodiment of the present invention, the auxiliaries and adjuvants available in agriculture such as solvents, surfactants, carriers, fillers, etc. Those skilled in the art can formulate the wild rose hip polysaccharide with these auxiliaries or adjuvants into common agricultural formulations such as aqueous solutions, suspensions, wettable powders, granules, etc., and the specific preparation methods refer to the conventional methods in agricultural combinations for preparation.

[0015] Optionally, the dosage form of the plant resistance inducer of the present invention can be an aqueous solution, a suspension, a wettable powder or a granule.

[0016] Generally, for suspensions, the auxiliaries or adjuvants that can be selected include methanol, ethylene glycol, carboxymethyl cellulose, xanthan gum, benzoic acid, etc.

[0017] Generally, for wettable powders, excipients or adjuvants that can be selected include sodium dodecylbenzenesulfonate, polyvinyl alcohol, carboxymethyl cellulose, etc.

[0018] Generally, for granules, excipients or adjuvants that can be selected include starch, gelatin, polyvinyl alcohol, diatomaceous earth, etc.

[0019] The plant resistance inducer of the present invention can be applied to the above-ground parts of plants by spraying. The preferred spraying time is before the occurrence of diseases. The concentration of the active ingredient in the spraying solution is 100 - 300 mg / L, and the spraying amount per single plant can be 20 - 60 mg (calculated based on wild rose polysaccharide). It has been verified that after spraying the plant resistance inducer of the present invention on plants, it can prevent plant diseases, especially wheat scab, wheat powdery mildew, rice sheath blight, tomato gray mold, and cucumber downy mildew.

[0020] The active ingredient of the resistance inducer of the present invention is plant polysaccharide, which is easy to obtain and is safe and harmless.

[0021] The plant resistance inducer in the present invention can effectively prevent various diseases of various plants and has wide applicability.

Specific Embodiments

[0022] The following embodiments are helpful for understanding the present invention, but do not limit the content of the present invention.

[0023] The average molecular weight of the wild rose polysaccharide used in the following embodiments is 97.58 kDa, and it is purchased from Lanzhou Woteles Biotechnology Co., Ltd.

[0024] Example 1 Anti - wheat - disease Activity of Wild Rose Polysaccharide

[0025] The pot - culture test method was adopted: Healthy wheat plants with similar growth conditions and not infected with diseases were selected and transplanted into pots, with 1 plant per pot, 10 pots in each group, and 4 replicates in each group. Clear water was selected as the control. The wild rose polysaccharide was formulated into an aqueous solution with a concentration of 200 mg / L and sprayed on each group of potted plants. Each spraying cycle was 5 days, and the spraying amount per single plant per time was 0.2 L. 5 days after the 3rd spraying, the wheat plants were inoculated with diseases. After culturing in a room - temperature environment for 14 days, the disease conditions of each group of wheat were recorded, and the disease index and induction effect were calculated according to the following grading standards and formulas.

[0026] Inoculation method of Fusarium graminearum: When the heading and flowering rate of wheat was 10%, 10 mL of a spore suspension of Fusarium graminearum with a concentration of 1×10 6 CFU / mL was evenly sprayed onto the wheat plants by the spraying method, once every 3 days, for a total of 3 sprays. After inoculation, it was placed in a culture room at a temperature of 20°C, with a relative humidity of 80% maintained, and the daily light - exposure time was 12 h.

[0027] Inoculation method for Blumeria graminis: At the one-leaf-and-one-heart stage of wheat, conidia of Blumeria graminis were inoculated onto wheat leaves by the spore shaking method, once every 3 days for a total of 3 times. After inoculation, the plants were placed in a cultivation chamber at 20°C, with a relative humidity of 80% and a daily light duration of 12 h.

[0028] The disease grading standard for Fusarium head blight of wheat refers to "NY-T1464.15-2007 Pesticide field efficacy test guidelines (I) Fungicides for controlling Fusarium head blight of wheat". The grading method (taking the ear as the unit) is as follows:

[0029] Grade 0: Disease-free;

[0030] Grade 1: The withered ear area accounts for less than of the total ear area;

[0031] Grade 3: The withered ear area accounts for

[0032] Grade 5: The withered ear area accounts for

[0033] Grade 7: The withered ear area accounts for or more of the total ear area.

[0034] The disease grading standard for powdery mildew of wheat refers to "GB-T17980.22-2000 Pesticide field efficacy test guidelines (I) Fungicides for controlling powdery mildew of cereals". The grading method (taking the leaf as the unit) is as follows:

[0035] Grade 0: No disease spots;

[0036] Grade 1: The disease spot area accounts for less than 5% of the entire leaf area;

[0037] Grade 3: The disease spot area accounts for 6% - 10% of the entire leaf area;

[0038] Grade 5: The disease spot area accounts for 11% - 20% of the entire leaf area;

[0039] Grade 7: The disease spot area accounts for 21% - 50% of the entire leaf area;

[0040] Grade 9: The disease spot area accounts for more than 51% of the entire leaf area.

[0041]

[0042]

[0043] Table 1 Disease index and induced resistance effect of wheat plants after treatment with Rosa roxburghii Tratt polysaccharide

[0044]

[0045] Note: Statistical analysis was performed using DPS 6.0 data processing software, and the Duncan's new multiple range method was used for significant difference analysis. Different lowercase letters marked after the data in the same column indicate significant differences (P < 0.05). The same below.

[0046] Table 1 shows that after treatment with 200 mg / L wild rose hip polysaccharide, the incidence of wheat scab and wheat powdery mildew both decreased to a certain extent, manifested as a decrease in the disease index, and the control effect on wheat scab was better than that on wheat powdery mildew.

[0047] Example 2 Anti-disease activity of wild rose hip polysaccharide against rice diseases

[0048] The pot experiment method was adopted: Healthy rice seedlings with similar growth conditions and not infected with diseases were selected and transplanted into pots, 1 plant per pot, 10 pots per group, and 4 replicates were carried out for each group. Clear water was selected as the control. The wild rose hip polysaccharide was prepared into an aqueous solution of 300 mg / L and sprayed on each group of potted plants. Each spraying cycle was 7 days, and the single spraying amount per plant was 0.2 L. 7 days after the third spraying, the rice plants were inoculated with diseases. After culturing in a room temperature environment for 7 days, the disease conditions of each group of plants were recorded, and the disease index and induced resistance effect were calculated according to the following grading standards and the formula in Example 1.

[0049] Inoculation method of Rhizoctonia solani: By the method of inoculating with fungal discs, Rhizoctonia solani was cultured in a Petri dish with potato agar medium. When the mycelium covered the Petri dish, fungal discs with a diameter of 5 mm were punched at the edge of the colony for the next inoculation. During inoculation, the rice leaf sheath was opened, and a fungal disc was sent into the opened leaf sheath with a dissecting needle. After inoculation, the leaf sheath was restored. One fungal disc was inoculated into each leaf sheath. After inoculation, it was placed in an incubator at a temperature of 20 °C, with a relative humidity of 80%, and a daily light time of 12 h.

[0050] Grading standards for rice sheath blight, referring to the method of Zhao Min et al. (Zhao Min, Chen Jialei, Yin Wei, et al. Experimental study on the control effects of 5 fungicides against rice sheath blight and false smut [J]. Journal of Biocontrol Science, 2021, 44(03): 300 - 304.):

[0051] Grade 0: The whole plant is disease-free

[0052] Grade 1: The leaf sheaths and leaves below the third leaf are diseased (taking the flag leaf as the first leaf)

[0053] Grade 2: The leaf sheaths and leaves below the second leaf are diseased

[0054] Grade 3: The leaf sheath or leaf blade of the flag leaf is diseased

[0055] Grade 4: The whole plant is diseased and withers prematurely

[0056] Table 2 Disease index and induced resistance effect of rice plants after treatment with Rosa roxburghii tratt polysaccharide

[0057]

[0058] As shown in Table 2, after treatment with 300 g / L Rosa roxburghii tratt polysaccharide, the incidence of sheath blight of rice was reduced, which proved that Rosa roxburghii tratt polysaccharide had a certain preventive effect on rice sheath blight.

[0059] Example 3 Anti-disease activity of Rosa roxburghii tratt polysaccharide against tomato diseases

[0060] The pot experiment method was adopted: Healthy tomato seedlings with similar growth conditions and not infected with diseases were selected and transplanted into pots, 1 plant per pot, 10 pots per group, and 4 replicates were carried out for each group. Fresh water was selected as the control. Rosa roxburghii tratt polysaccharide was formulated into an aqueous solution of 100 mg / L and sprayed on each group of potted plants. Each spraying cycle was 5 days, and the single spraying amount per plant was 0.2 L. 5 days after the third spraying, the tomato plants were inoculated with diseases. After culturing for 7 days in a room temperature environment, the disease conditions of each group of plants were recorded, and the disease index and induced resistance effect were calculated according to the following grading standard and the formula in Example 1.

[0061] Inoculation method of Botrytis cinerea on tomato: Select tomato seedlings with similar growth conditions and trifoliolate compound leaves, and inoculate 10 mL of Botrytis cinerea spore suspension with a spore concentration of 1×10 6 CFU / mL on the leaf surface by the spraying method. After inoculation, it was placed in a culture room at a temperature of 20 °C, with a relative humidity of 80%, and the daily light time was 12 h.

[0062] The grading standard of tomato gray mold disease refers to the method of Zhang Meng et al. (Zhang Meng, Zhai Qianhang, Zhu Chengyu, Zheng Lining, Zhang Hao. Joint toxicity of Pseudomonas fluorescens YG-1 and fungicides against tomato gray mold disease [J]. China Vegetables, 2021(05): 70-74.):

[0063] Grade 0: No disease spots on the leaves

[0064] Grade 1: 1-3 disease spots on the leaves

[0065] Grade 3: 4-6 disease spots on the leaves

[0066] Grade 5: 7-10 disease spots on the leaves

[0067] Grade 7: 11-20 disease spots on the leaves, and some are densely packed

[0068] Grade 9: The disease spots on the leaves are dense, accounting for more than 25% of the total leaf area

[0069] Table 3 Disease index and induced resistance effect of tomato plants after treatment with Rosa roxburghii tratt polysaccharide

[0070]

[0071] Table 3 shows that when the concentration is 100 mg / L, spraying the elicitor containing wild rose hip polysaccharide has a strong protective effect on tomato gray mold, and the disease index decreases significantly.

[0072] Example 4 Anti-disease activity of wild rose hip polysaccharide against cucumber diseases

[0073] The pot experiment method was adopted: Healthy cucumber seedlings with similar growth conditions and no diseases were selected, transplanted into pots, 1 plant per pot, 10 pots per group, and each group was repeated 4 times. Clear water was selected as the control. The wild rose hip polysaccharide was prepared into an aqueous solution with a concentration of 100 mg / L, and the potted plants in each group were sprayed. Each spraying cycle was 7 days, and the single spraying amount per plant was 0.2 L. 7 days after the third spraying, the cucumber plants were inoculated with diseases. After culturing at room temperature for 10 days, 10 leaves were randomly selected from each plant for disease investigation, and the disease index and elicitor effect were calculated according to the following grading standard and the formula in Example 1.

[0074] Inoculation method of Pseudoperonospora cubensis: The cucumber leaves were inoculated with 10 mL of cucumber downy mildew spore suspension with a concentration of 1×10 5 CU / / mL by the spraying method, once a day for a total of 3 times. After inoculation, it was placed in a culture room at a temperature of 20 °C, with a relative humidity of 80%, and a daily light time of 12 h.

[0075] The grading standard for cucumber downy mildew refers to the method of Wang Chengxiang et al. (Wang Chengxiang, Liu Zhenlong, Zhang Ruihua, et al. Field efficacy evaluation of 6 fungicides against cucumber downy mildew [J]. Journal of Biocontrol Science, 2021, 44(03): 284-287.):

[0076] Grade 0: No disease spots on the whole leaf;

[0077] Grade 1: The disease spot area accounts for less than 5% of the entire leaf area

[0078] Grade 3: The disease spot area accounts for 6-10% of the entire leaf area

[0079] Grade 5: The disease spot area accounts for 11-25% of the entire leaf area

[0080] Grade 7: The disease spot area accounts for 26-50% of the entire leaf area

[0081] Grade 9: The disease spot area accounts for more than 50% of the entire leaf area

[0082] Table 4 Disease index and elicitor effect of tomato plants after treatment with wild rose hip polysaccharide

[0083]

[0084] Table 4 shows that when the concentration of Rosa roxburghii polysaccharide is 100 mg / L, the occurrence degree of cucumber downy mildew is reduced, which proves that Rosa roxburghii polysaccharide has a certain preventive effect on rice sheath blight.

[0085] The above embodiments describe the technical solutions of the present invention non - restrictively. Those skilled in the art can draw on the content of the present invention and appropriately change raw materials, process conditions and other links to achieve corresponding other purposes. Their related changes do not depart from the content of the present invention. All similar substitutions and modifications are obvious to those skilled in the art and are regarded as being included within the scope of the present invention.

Claims

1. Application of wild rose roxb. polysaccharide in resisting plant diseases, wherein the average molecular weight of the wild rose roxb. polysaccharide is 97.58 kDa, the plant diseases are wheat diseases, rice diseases, tomato diseases and cucumber diseases, and the wheat disease is wheat scab ( Fusarium graminearum ), or wheat powdery mildew ( Blumeria graminis ), the rice disease is rice sheath blight ( Rhizoctonia solani ), the tomato disease is tomato gray mold ( Botrytis cinerea ), and the cucumber disease is cucumber downy mildew ( Pseudoperonospora cubensis ); before the occurrence of plant diseases, a plant resistance inducer containing wild rose roxb. polysaccharide is applied to the above-ground part of the plant by spraying, and the spraying amount per plant is 20-60 mg / plant calculated by wild rose roxb. polysaccharide; the treatment concentration for the wheat disease is 200 mg / L calculated by wild rose roxb. polysaccharide, the treatment concentration for the rice disease is 300 mg / L calculated by wild rose roxb. polysaccharide, and the treatment concentrations for the tomato disease and cucumber disease are 100 mg / L calculated by wild rose roxb. polysaccharide.

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