RSD raw material for reducing continuous cropping obstacles of peppers and application of RSD raw material

Abstract

The invention provides an RSD raw material for reducing pepper continuous cropping obstacles and application thereof, and the RSD raw material comprises pepper straws, especially pepper straws and rice straws. When the RSD raw material provided by the invention is used for treating soil, the effects of promoting growth, increasing yield, improving quality and reducing diseases can be achieved, and the RSD raw material has a synergistic effect in the aspects of chili yield and quality formation and soil fertility improvement.

Description

Technical Field

[0001] The invention belongs to the technical field of soil improvement, and particularly relates to RSD raw materials for alleviating the obstacles of pepper continuous cropping and application thereof. Background Art

[0002] As the vegetable with the largest planting area and the condiment with the largest consumption in my country, pepper is favored by the majority of growers and consumers due to its high economic and nutritional value. However, prominent problems such as the deterioration of soil physical and chemical properties, the intensification of pests and diseases, and the imbalance of microbial communities have become the key problems restricting the improvement of pepper yield and quality. Effective measures are urgently needed to alleviate the obstacles of continuous cropping to ensure the sustainable development of the pepper industry.

[0003] Strong soil reduction (RSD) is a remediation technology before crop planting. This method can effectively repair the physical and chemical properties of degraded soil, quickly kill soil-borne pathogens, improve soil microbial flora, and maintain healthy plant growth by using the products of anaerobic decomposition of organic materials and reducing conditions. Strong soil reduction treatment can effectively prevent and control the obstacles of continuous cropping of melon and vegetable soil. On the one hand, RSD can effectively improve the physical and chemical properties of soil. After treatment, the pH, alkaline nitrogen, available potassium, and available phosphorus content of soil are greatly improved. On the other hand, RSD can also be used to prevent and control soil-borne diseases in melon and vegetable crops. Studies have found that RSD effectively prevents and controls tomato wilt caused by Verticilliumdahliae, radish root rot caused by Rhizoctoniasolani, watermelon wilt caused by Fusariumoxysporum, and pepper root rot caused by Phytophthoraspp. At the same time, RSD treatment can also effectively improve soil microbial flora, increase beneficial bacteria, and reduce the relative abundance of pathogens. The restoration of soil physical and chemical properties, prevention and control of pests and diseases, and improvement of microbial flora by RSD treatment are directly reflected in the improvement of crop yield and quality. RSD treatment technology has been proven to increase yield and improve quality on vegetable crops such as tomatoes, cucumbers, and peppers.

[0004] However, current research is mostly focused on indoor cultivation and facility cultivation conditions, and research under open field conditions is relatively lacking. The field soil environment is more complex and changeable than that of the indoor environment, and the effect of RSD treatment is uncertain. At the same time, the remediation effect of RSD treatment on degraded soil is closely related to the type of organic material added. Studies have shown that there is a negative correlation between the C / N of organic materials and the bactericidal effect of RSD technology. In summary, in field in-situ practice, in addition to considering the differences in the remediation effects of different organic materials and application technologies, the principles of convenient material collection and economic feasibility should also be followed. Therefore, a better RSD treatment plan needs to be proposed. Summary of the invention

[0005] In order to solve the technical problems existing in the prior art, the present invention provides RSD raw materials and applications thereof for reducing pepper continuous cropping obstacles, wherein the RSD raw materials include pepper straw, in particular pepper straw and rice straw. Using the RSD raw materials provided by the present invention to treat soil can achieve the effects of promoting growth, increasing production, improving quality, and reducing disease, and has a synergistic effect in the formation of pepper yield quality and improvement of soil fertility.

[0006] In order to achieve the above object, the present invention adopts the following technical solution:

[0007] A first aspect of the present invention provides a RSD raw material, which comprises pepper stalks.

[0008] In the present invention, RSD is a strong reducing soil sterilization method, and the RSD raw materials (carbon sources) also include other organic materials, wherein the organic materials include dry organic materials and easily degradable liquid compounds.

[0009] The degree of soil continuous cropping disorder varies from place to place. According to the degree of soil continuous cropping disorder, the type and amount of organic materials required for RSD can be selected, especially straw-based organic materials with abundant local resources. However, the use of organic materials is not the most effective and economical if it is the largest. Appropriate adjustments should be made based on the actual conditions such as soil-borne pathogens and their density, treatment temperature and treatment time.

[0010] In the present invention, dry organic materials include but are not limited to agricultural waste, poultry manure, and fresh cover crops, and easily degradable liquid compounds include but are not limited to ethanol, acetic acid, and glucose. Among them, agricultural waste includes but is not limited to plant straw and crop residues, plant straw includes but is not limited to wheat straw, rice straw, corn straw, sorghum straw, peanut straw, soybean straw, potato straw, and sweet potato straw, crop residues include but are not limited to wheat bran, rice bran, bagasse, and rice husks, poultry manure includes but is not limited to chicken manure and pig manure, and fresh cover crops include but are not limited to broccoli, mustard, and arugula.

[0011] In the present invention, solid organic materials are preferably used for soils with low organic matter content and compaction; solid or water-soluble organic materials can be used for soils with high organic matter content and well-developed aggregate structure.

[0012] In the present invention, plant straws need to be air-dried before use, but fresh plant tissues do not need to be air-dried.

[0013] In the existing technology, most organic materials have achieved good sterilization effects, but they show differences, which is closely related to the physical and chemical properties of the organic materials themselves. Organic materials are rich in organic carbon and can be divided into two types: easily degradable and difficult to degrade (such as cellulose and lignin).

[0014] In the early stage of RSD treatment, Firmicutes used organic matter to reproduce in large numbers and became the dominant population. Among the dominant genera, the carbon source decomposers Ruminococcus and acid-producing bacteria (such as Clostridia and Coprococcus) were the majority. Some scholars speculate that in the early stage of RSD treatment, carbon source decomposers can quickly decompose the easily degradable organic carbon in the material and cooperate with acid-producing bacteria to produce organic acids. In the later stage, the remaining part of the organic matter is a difficult-to-degrade organic carbon source, which is slowly decomposed by microorganisms, and thus the acid production capacity is also weak. The organic acids produced during the degradation of these organic materials are the most important substances for sterilization, but due to the different contents of easily oxidizable organic carbon in the materials, the ability to produce organic acids varies. In addition, the beneficial bacteria (such as Bacillus) produced during the RSD treatment process use easily degradable organic carbon sources to reproduce in large numbers. The antagonism, competition and parasitism of these beneficial microorganisms can better inhibit pathogens.

[0015] Under the condition of roughly the same oxidizable organic carbon, the higher the total nitrogen, the better the bactericidal effect. This may be related to the ammoniation effect. The toxic ammonia produced during the decomposition of organic nitrogen by microorganisms has a bactericidal effect. The higher the total nitrogen, the greater the intensity of the ammoniation effect, the more ammonia is produced, and thus the better the bactericidal effect.

[0016] The carbon-nitrogen ratio (C / N) of agricultural organic materials currently used ranges from 6.99 to 159.23. For example, alfalfa, wheat bran, rice bran, rapeseed meal, corn stalks, etc. are low C / N organic materials, and bagasse and sugarcane leaves are high C / N organic materials. Low C / N organic materials have a higher sterilization rate and can promote higher reducing conditions in the soil, resulting in an increase in the production of nitrogen-containing compounds (such as ammonia and nitrite) in the soil, thereby better inhibiting fungal pathogens.

[0017] If the C / N ratio of organic materials used in RSD treatment is too low, it will lead to nitrogen loss, while if the C / N ratio is too high, the soil after treatment will be nitrogen deficient, and more nitrogen fertilizer needs to be applied to supplement it. RSD treatment with high oxidizable organic carbon and low C / N organic materials has better sterilization effect.

[0018] Furthermore, the organic material is selected from dry organic material.

[0019] Furthermore, the dry organic material is selected from agricultural waste.

[0020] Furthermore, the agricultural waste is selected from plant straw.

[0021] Furthermore, the plant straw is selected from rice straw.

[0022] In the present invention, the mass ratio of the pepper straw to other plant straws is not limited, and as long as it can play a role in reducing the obstacles of continuous cropping, it falls within the protection scope of the present invention.

[0023] In the present invention, the pepper stalks may be more or less than other plant stalks.

[0024] Furthermore, the mass ratio of the pepper straw to other plant straws is 1:1-100:1.

[0025] Furthermore, the mass ratio of the pepper straw to other plant straws is 1:1-10:1.

[0026] Furthermore, the mass ratio of the pepper straw to other plant straws is 1:1.

[0027] Furthermore, the raw materials also include soil fertilizer.

[0028] Furthermore, the soil fertilizer includes organic fertilizer, inorganic fertilizer and biological fertilizer.

[0029] In the present invention, organic fertilizers include but are not limited to manure fertilizer, composted manure, green manure, miscellaneous fertilizers, and commercial organic fertilizers.

[0030] In the present invention, manure fertilizer includes but is not limited to human manure fertilizer, livestock manure fertilizer, and poultry manure fertilizer. Livestock manure fertilizer comes from, but is not limited to, pigs, cattle, and sheep, and poultry manure fertilizer comes from, but is not limited to, chickens, ducks, and geese.

[0031] In the present invention, compost includes but is not limited to compost, fermented manure, and biogas tank fertilizer; green manure includes but is not limited to straw and leguminous green manure; miscellaneous fertilizer includes but is not limited to peat (peat), humic acid fertilizer, cake fertilizer, soil fertilizer (river mud, lake mud, pond mud, sewage, sludge), garbage fertilizer and other industrial and agricultural waste; commercial organic fertilizer includes but is not limited to various organic fertilizers produced in factories.

[0032] Furthermore, the organic fertilizer comes from plants and / or animals.

[0033] In the present invention, inorganic fertilizers are also called "chemical fertilizers", which are fertilizers composed of inorganic substances. Inorganic fertilizers include but are not limited to nitrogen fertilizers, phosphate fertilizers, potash fertilizers and other single fertilizers or compound fertilizers, wherein nitrogen fertilizers include but are not limited to ammonia water, ammonium bicarbonate, ammonium sulfate, ammonium chloride; phosphate fertilizers include but are not limited to superphosphate, calcium magnesium phosphate fertilizer, phosphate rock powder; potash fertilizers include but are not limited to potassium chloride, potassium phosphate; compound fertilizers include but are not limited to ammonium phosphate, nitrate phosphorus, potassium nitrate, potassium dihydrogen phosphate. In addition, there are trace element fertilizers, such as iron fertilizers, boron fertilizers, manganese fertilizers, copper fertilizers, zinc fertilizers, molybdenum fertilizers, etc.

[0034] In the present invention, there are many types of biological fertilizers, and biological fertilizer products are generally divided into two categories: one is biological fertilizer in a narrow sense, which refers to the increase in the supply of plant nutrients through the life activities of microorganisms, including increasing the total supply of plant nutrients in the soil and production environment, resulting in improved plant nutritional status and increased yields. The representative variety of this type of biological fertilizer is rhizobium fertilizer; the other is biological fertilizer in a broad sense, which refers to the life activities of the microorganisms therein, which can not only increase the supply of plant nutrients, but also produce plant growth hormones, promote the absorption and utilization of nutrients by plants, or antagonize the pathogenic effects of certain pathogenic microorganisms, reduce crop diseases and insect pests and promote the increase of crop yields.

[0035] In the present invention, biological fertilizers include but are not limited to bacterial fertilizers, actinomycete fertilizers, fungal fertilizers, algae fertilizers, and compound microbial fertilizers. Among them, bacterial fertilizers include but are not limited to rhizobium fertilizers, nitrogen-fixing fertilizers, phosphate-dissolving fertilizers, potassium-dissolving fertilizers, and photosynthetic fertilizers; actinomycete fertilizers include but are not limited to antibiotic fertilizers; fungal fertilizers include but are not limited to ectomycorrhizal agents and endomycorrhizal agents; algae fertilizers include but are not limited to nitrogen-fixing cyanobacteria fertilizers; and compound microbial fertilizers are fertilizers formed by combining two or more microorganisms in a certain proportion.

[0036] The second aspect of the present invention provides a method for reducing obstacles to continuous pepper cropping, the method comprising treating soil with the raw materials described in the first aspect of the present invention.

[0037] The higher the soil temperature during RSD treatment, the shorter the RSD treatment time. When the treatment temperature is low, a longer treatment time is required. The specific treatment time can be adjusted according to the application amount of organic material, temperature, the number of soil-borne pathogens and the effective time available for treatment.

[0038] Furthermore, the usage of the raw material is 0.31 to 50 t·hm -2 .

[0039] Furthermore, the usage of the raw material is 5 to 15 t·hm -2 .

[0040] Furthermore, the usage of the raw material is 15t·hm -2 .

[0041] Furthermore, the soil temperature during the treatment was 20-40°C.

[0042] Furthermore, the soil temperature during the treatment is 25-35°C. Examples include, but are not limited to, 25°C, 26°C, 27°C, 28°C, 29°C, 30°C, 31°C, 32°C, 33°C, 34°C, and 35°C.

[0043] Furthermore, the soil treatment time is 14 to 45 days.

[0044] Furthermore, the treatment time of the treated soil is 30 days.

[0045] Furthermore, the method comprises treating the soil with the raw material described in the first aspect of the present invention, creating a strong reducing environment for the soil, and drying the soil.

[0046] In the present invention, the soil can be isolated from the atmosphere by irrigating the soil until it is saturated with water, covering it with plastic film or flooding it with water, and a strong reducing environment can be quickly established. For a small amount of soil with poor water holding capacity or inconvenient to flood it, film covering can be selected. Transparent plastic film is conducive to sunlight exposure and increasing soil temperature, and opaque film has a certain effect on controlling weeds.

[0047] Furthermore, the drying time is 5 to 20 days, and examples include but are not limited to 10 days, 11 days, 12 days, 13 days, 14 days, 15 days, 16 days, 17 days, 18 days, 19 days, and 20 days.

[0048] Furthermore, the drying time is 15 days.

[0049] Further, the method comprises broadcasting 15 t·hm in the pepper continuous cropping area. -2 The raw material of the first aspect of the present invention is mixed with cultivated soil, covered with film, and the soil is irrigated under the film to saturation, and treated for 30 days, during which the soil temperature is 25-35° C., punched with holes, and aired for 15 days.

[0050] Furthermore, the method also includes using it sequentially, simultaneously or cross-wise with other methods for preventing and controlling continuous cropping disorders.

[0051] In the present invention, simultaneously means that two methods are used synchronously. Sequential use means that different methods are used successively within a time range, so that the two methods can work in reducing continuous cropping obstacles within the same time range, wherein, as long as the effect of the previous method is still maintained within the time range, it can be considered to be within the same time range. Therefore, sequential use allows the use of one method after another method.

[0052] Furthermore, the other methods for preventing and controlling continuous cropping obstacles include but are not limited to physical measures, chemical measures, biological measures, application of resistant varieties and / or grafting of resistant varieties.

[0053] Furthermore, the physical measures include but are not limited to high temperature greenhouses, crop rotation, intercropping, relay cropping, irrigation and salt removal, short-term flooding, and planting of filler crops.

[0054] In the present invention, crop rotation refers to a planting method in which different crops or multiple cropping combinations are planted sequentially between seasons and years on the same field, such as the three-year rotation of soybeans → wheat → corn with one crop per year, which is a single crop rotation carried out between years; under the condition of multiple crops per year, there are both annual rotations and intra-annual rotations, such as the green manure-rice-rice → rapeseed-rice → wheat-rice-rice rotation in the south. Intercropping refers to a planting method in which two or more crops are planted alternately in rows or strips on the same field during the same growth period. Intercropping refers to a planting method in which the crops of the next season are sown or transplanted between the rows in the late growth period of the crops of the previous season.

[0055] Furthermore, the chemical measures include but are not limited to soil fumigation with chemical agents and application of lime. Although the use of chemical agents can kill insects, fungi, and weeds, and can prevent and control root rot, anthracnose, gray spot, damping-off, etc., they can also pollute the environment, reduce biological transformation capacity, and destroy the ecological balance of the soil, so they need to be used rationally and scientifically.

[0056] Furthermore, the biological measures include but are not limited to the application of microbial fertilizer or biological organic fertilizer, and biological antagonistic agents.

[0057] Furthermore, the use of salt-alkali-resistant and replant-resistant rootstocks to graft high-quality varieties can overcome the obstacles of continuous cropping to a certain extent.

[0058] Furthermore, the other methods for preventing and controlling continuous cropping obstacles also include the use of soil conditioners. Soil conditioners have the functions of drought resistance, water conservation, fertilization, neutralization of acidic soil, improvement of surface soil quality, increase of surface soil organic matter, balance of bottom soil nutrient loss, and further enhancement of soil permeability. Mineral soil conditioners (such as desulfurization waste, lime, alkali residue, etc.) can neutralize acidic substances and improve acidic soil; if mixed with various natural active biological organic fertilizers, they can increase the biomass of beneficial soil microorganisms and improve the activity of antioxidant enzymes.

[0059] In the present invention, for facility soil with serious continuous cropping obstacles, RSD treatment can be carried out once every 2 to 4 crops to maintain sustainable and green production of facility vegetables.

[0060] The third aspect of the present invention provides any of the following applications:

[0061] (1) Use of the raw material described in the first aspect of the present invention in alleviating obstacles caused by continuous pepper cropping.

[0062] (2) Use of the raw material described in the first aspect of the present invention in promoting the growth of peppers.

[0063] (3) Use of the raw material described in the first aspect of the present invention in reducing the incidence of pepper disease.

[0064] (4) Use of the raw material described in the first aspect of the present invention in promoting pepper photosynthesis.

[0065] (5) Application of the raw material described in the first aspect of the present invention in increasing pepper yield.

[0066] (6) Application of the raw material described in the first aspect of the present invention in improving the quality of peppers.

[0067] (7) Use of the raw material described in the first aspect of the present invention in improving soil fertility.

[0068] The invention has the advantages and beneficial effects: the invention provides RSD raw materials for reducing pepper continuous cropping obstacles and their application, wherein the RSD raw materials include pepper straw, in particular pepper straw and rice straw. Using the RSD raw materials provided by the invention to treat soil can achieve the effects of promoting growth, increasing yield, improving quality, and reducing disease, and has a synergistic effect in the formation of pepper yield quality and the improvement of soil fertility. BRIEF DESCRIPTION OF THE DRAWINGS

[0069] Figure 1 This is a graph showing the effects of different treatments on the growth of continuously cropped peppers.

[0070] Figure 2 This is a graph showing the effects of different treatments on the photosynthetic characteristics of continuously cropped peppers.

[0071] Figure 3 This is a graph showing the effects of different treatments on enzyme activity in continuously cropped pepper leaves.

[0072] Figure 4 It is the normalized radar chart of various indicators under different organic material treatments.

[0073] Figure 5 It is the heat map of the correlation between each indicator under different treatments. DETAILED DESCRIPTION

[0074] The disclosure above generally describes the present invention. A more complete understanding can be obtained with reference to the following specific embodiments. The purpose of describing these embodiments is only for illustration and is not intended to limit the scope of the present invention. Form changes and equivalent substitutions are considered to be circumstances that may suggest or confer convenience. Although specific terms are used in this article, the purpose of these terms is descriptive rather than limiting.

[0075] Example

[0076] 1. Materials

[0077] Test site: The test site is located in the Guanzhuang base of the Pepper Research Institute of Guizhou Academy of Agricultural Sciences in Zunyi (27°44′N, 107°12′E). The area has a subtropical monsoon climate with abundant rainfall and sufficient sunshine. The soil type of the test plot is yellow soil. The basic physical and chemical properties of the test soil are: organic matter 13.35g·kg -1 , total nitrogen 1.82g·kg -1 , available phosphorus 16.53 mg kg -1 , fast-acting potassium 207.66 mg kg -1 , pH 6.92. This plot has been planted with peppers for 8 consecutive years, and the continuous cropping obstacle is relatively serious, manifested in the frequent occurrence of pepper diseases and pests and the decline in yield.

[0078] Test crop: "Layan 101" was independently bred by Guizhou Pepper Research Institute. The seeds were surface sterilized with 10% H2O2 for 10 minutes, then rinsed with distilled water, germinated in a 30℃ constant temperature incubator for 24 hours, and then floated in a seedling tray filled with a special seedling medium for peppers. The peppers were transplanted when they grew 4-5 true leaves.

[0079] Test material: Pepper straw after air drying and coarse powder, total nitrogen content is 7.80g·kg -1 , the total carbon content is 453.74g·kg -1 The carbon-nitrogen ratio is 58.17. The rice straw is air-dried and coarsely powdered for later use, with a total nitrogen content of 10.14 g kg -1 , total carbon content 401.34g·kg -1 , the carbon-nitrogen ratio is 39.58.

[0080] 2. Methods

[0081] (1) Experimental design: There were 3 treatments in the experiment: 1) CK-no organic materials added; 2) RSD1-addition of pepper straw; 3) RSD2-addition of rice straw; 4) RSD3-addition of pepper straw and rice straw mixed with organic materials of equal mass (m / m = 1:1). Each treatment group had 3 replicate plots, with a plot area of ​​20 m 2 Isolation rows were set between different plots. The RSD treatment process was as follows: After different treatment plots were divided on the pepper continuous cropping plot, 15 t·hm was evenly applied on the soil surface of the corresponding treatment plot. -2 Organic materials were mixed with the tillage layer soil by a rotary tiller. After ridge formation and film covering, the soil was irrigated to saturation under the film. The treatment lasted for 30 days, and the soil temperature was 25-35°C during the treatment period. After the treatment, the peppers were punched with a hole puncher. After drying for 15 days, compound fertilizer (N:P:K=15:15:15, 750kg·hm -2), no topdressing. Pepper seedlings of similar size were selected for transplanting, with the transplanting specification of row spacing × plant spacing = 130 cm × 40 cm, and double planting. Except for the application of different organic materials, the rest of the field management was the same in each plot.

[0082] (2) Growth index detection: The peppers were transplanted in May 2023 and harvested in September. Ten peppers were randomly listed in each plot for measurement. The plant height, stem thickness, and spread of the peppers were measured with a ruler and vernier caliper before harvesting. The number of diseased plants on the leaves and fruits of peppers in each plot was investigated and counted, and the total incidence rate was calculated. The peppers were harvested by the aboveground part and the root part. The aboveground and root samples of the plants were washed and dried with filter paper, and then placed in an oven. They were first sterilized at 105°C for 30 minutes and then dried at 70°C until the sample had a constant weight, and the dry weight was calculated. The incidence rate calculation formula is:

[0083] Incidence rate = number of pepper plants with disease / total number of plants surveyed × 100%

[0084] (3) Photosynthetic characteristics detection: The LI-6800 portable photosynthetic system analyzer produced by Li-Cor Company of the United States was used to select the newly mature leaves of the pepper plants from the third node from the top to the bottom from 09:00 to 11:00 in the morning during the flowering period of pepper (about 30 days after transplanting), and the net photosynthetic rate (Pn), stomatal conductance (Gs), transpiration rate (Tr), and intercellular CO2 concentration (Ci) of the pepper leaves were measured. Four plants were randomly selected from each treatment area, and three representative leaves of each pepper plant were selected for measurement and the average value was taken. The light intensity was 1200μmol.m -2 .s -1 The SPAD value was determined using a SPAD-502 chlorophyll meter.

[0085] (4) Leaf enzyme activity detection: According to the kit instructions of Beijing Solebow Technology Co., Ltd., the micro-volume method (Spectrophotometer) was used with an enzyme reader (ThermoFisher Multiskan GO1510) to determine the activities of peroxidase (POD), superoxide dismutase (SOD), polyphenol oxidase (PPO), catalase (CAT), and phenylalanine ammonia lyase (PAL) in pepper leaves.

[0086] (5) Yield and quality index detection: The yield and composition factors of peppers in each plot were statistically calculated according to the yield measurement method and calibration coefficient in DB52 / T976-2014. The crude fiber content was determined by reference to GB / T5009.10-2003 "Determination of crude fiber in plant foods"; the crude protein content was determined by reference to GB5009.5-2016 "Determination of protein in foods" Kjeldahl nitrogen determination method; the crude fat content test method was determined by reference to GB5009.6-2016 "Determination of fat in foods"; the VC of peppers was determined by potassium iodate titration, and the soluble solid matter was determined by refractometer (DR-M2).

[0087] (6) Soil nutrient testing: Soil organic matter content was determined by potassium dichromate-external heating method (K2Cr2O7-H2SO4 method); soil alkaline nitrogen content was determined by alkaline diffusion method; soil available phosphorus was determined by NaHCO3 extraction-molybdenum antimony colorimetric method; available potassium was determined by NH4OAc extraction-flame photometry; total nitrogen was determined by Kjeldahl method and Kjeldahl nitrogen analyzer (FOSSKT8000); total phosphorus was determined by HF digestion with HClO4-H2SO4 method and microplate reader (ThermoFisherMultiskanGO1510); total potassium was determined by HF-HClO4 digestion and flame photometer. pH value was determined by glass electrode method (Shanghai Precision Scientific Instrument Co., Ltd., Lei Mag pHS-3C), and the water-soil ratio was 2.5:1.

[0088] (7) Evaluation of soil fertility comprehensive index: This paper selects eight indicators, including pH, organic matter, total nitrogen, total phosphorus, total potassium, alkaline nitrogen, available phosphorus, and available potassium, and uses a fuzzy comprehensive evaluation model to evaluate the fertility of cultivated land soil. The soil comprehensive fertility evaluation index value is determined by the membership value and the weight coefficient. The calculation formula of the soil comprehensive fertility index (IFI) is as follows:

[0089]

[0090] Where: Wi and Pi represent the weight and membership value of the i-th item respectively; n represents the number of evaluation indicators. IFI values ​​range from 0 to 1. The larger the IFI value, the higher the comprehensive soil fertility. Calculation of membership value: Establish the membership function of each evaluation indicator, calculate its membership value, and use it to represent the state value of each fertility indicator. According to the crop effect curve, the membership function can be divided into parabolic type and S type.

[0091] Parabolic membership function:

[0092]

[0093] S-type membership function:

[0094]

[0095] Allocation of weight values: Adopt objective principal component analysis to determine the index weight values. Perform principal component analysis on all participating indexes. The ratio of the common factor variance of each index to the sum of the common factor variances of all indexes is the weight value of the index.

[0096] Table 1 The values ​​of turning points in the membership function curve

[0097]

[0098] (8) Data were collated and analyzed using Excel 2010 and SPSS 19.0. Data plotting was performed using Origin 9.1. The pepper growth index, yield index, quality index, and photosynthetic characteristic index in the comprehensive analysis were obtained by multiplying the weight of each individual index by the principal component (PCA) eigenvalue.

[0099] 3. Results

[0100] (1) Effects of different organic material RSD on the growth of continuously cropped peppers: Figure 1 It can be seen that the RSD treatments with different organic materials as raw materials have inconsistent effects on the growth of continuously cropped peppers. Different treatments have no significant effect on pepper plant height. Compared with CK, the RSD treatment slightly increased the thickness of pepper stems, but the difference was not significant. Compared with CK, RSD2 and RSD3 treatments significantly increased the biomass of pepper roots and aboveground parts, and both reached the maximum in RSD3 treatment, increasing by 43.72% and 19.68% respectively (P < 0.05). It is worth noting that no matter which organic material is used as raw material for RSD treatment, it can significantly reduce the incidence of continuously cropped peppers. Compared with CK, RSD1, RSD2, and RSD3 treatments reduced the incidence of continuously cropped peppers by 18.13% (P < 0.05), 12.44% (P < 0.05), and 35.33% (P < 0.05), respectively. The incidence of peppers reached the lowest in RSD3 treatment, only 29.51%.

[0101] (2) Effects of different organic material RSD on photosynthetic characteristics and enzyme activities of pepper leaves: Results ( Figure 2) It can be seen that there are significant differences in the photosynthetic characteristics of peppers between different treatments. RSD treatment can significantly enhance the photosynthesis of peppers and improve photosynthetic efficiency. Compared with CK, RSD treatment significantly increased the net photosynthetic rate of leaves, but the difference between different materials was not significant. Stomatal conductance has the same change trend. There was no significant change in the intercellular carbon dioxide concentration of pepper leaves under different treatment conditions. RSD treatment significantly increased the transpiration rate and SPAD value of pepper leaves, both of which reached the maximum in RSD1 treatment, which were significantly increased by 33.49% and 35.13% respectively compared with CK.

[0102] Different treatments had significant effects on the enzyme activities in pepper leaves ( Figure 3 ). The activity of superoxide dismutase (SOD) reached the highest level in CK treatment, while RSD1 and RSD3 treatments significantly reduced the activity, and there was no significant difference between RSD2 treatment and CK treatment. The activity of phenylalanine ammonia lyase (PAL) reached the highest level in RSD2 treatment and the lowest level in RSD1 treatment, and there was no significant difference between RSD3 and CK treatments. Compared with CK, RSD1 and RSD3 treatments significantly increased the activity of polyphenol oxidase (PPO) in pepper leaves, by 81.11% and 217.62%, respectively. The activity of catalase (CAT) reached the highest level in CK treatment, and there was no significant difference between it and RSD2 treatment. Compared with CK, RSD1 and RSD3 treatments significantly reduced CAT activity, but there was no significant difference between the two. Peroxidase (POD) reached the lowest level in CK treatment and the highest level in RSD1 treatment, and was significantly higher than that in CK and RSD2 treatments.

[0103] (3) Effects of different organic material RSD on yield and quality of continuously cropped pepper: RSD treatment had a significant effect of increasing yield and improving quality (Table 2). Compared with CK, different RSD treatments could significantly increase the number of pepper fruits, fruit weight per plant, average single fruit weight, and total yield. The total yield of pepper reached the maximum in RSD2 treatment, which was significantly increased by 23.67% compared with CK. RSD treatment significantly increased the VC content of pepper fruit, and the RSD1, RSD2, and RSD3 treatments were 1.25, 1.69, and 1.47 times that of CK treatment, respectively. The soluble solid content and crude protein content reached the maximum in RSD2 treatment, which were significantly improved compared with CK treatment, but there was no significant difference between different RSD treatments.

[0104] Table 2 Effects of different treatments on yield and quality of continuous cropping pepper

[0105]

[0106] Note: Different letters in the same column indicate significant differences among different treatments (P<0.05). The same below.

[0107] (4) Effects of different organic material RSD on soil nutrients of continuously cropped peppers: Compared with CK, soil pH, alkaline nitrogen, available potassium, and organic matter content all showed an increasing trend in the RSD treatment (Table 3). The soil pH value was the lowest in the CK treatment. The RSD treatment significantly increased the soil pH value, but there was no significant difference between the RSD treatments of different materials. The soil alkaline nitrogen and available potassium contents reached the maximum in the RSD1 and RSD3 treatments, respectively, which were significantly increased by 12.57% and 17.67% compared with the CK treatment, respectively. The RSD treatment increased the soil organic matter content, which reached the maximum in the RSD1 treatment, which was 20.24% higher than the CK treatment. It is worth noting that, compared with the CK treatment, RSD significantly reduced the soil available phosphorus content, and there was no significant difference between different RSD treatments.

[0108] Table 3 Effects of different treatments on soil nutrients in continuous pepper cropping

[0109]

[0110]

[0111] (5) Comprehensive evaluation of pepper continuous cropping system under different organic material RSD treatments: Figure 4 The changes in growth, yield quality, and soil fertility of peppers grown continuously under different organic material RSD treatments are shown. The growth index, photosynthetic characteristic index, yield index, and quality index evaluated in this study are obtained by multiplying the weight of each individual index by the eigenvalue of the principal component (PCA). The comprehensive soil fertility index is calculated using a fuzzy comprehensive evaluation model. In order to solve the problem of different scales of these indicators, their values ​​are normalized and presented using a radar chart. Figure 4 It can be seen from the position of each index on the coordinate axis that the contribution values ​​of pepper growth, yield, and quality indexes in the CK group are 0.57, 0.25, and 0.56, respectively. This shows that the most direct manifestation of pepper continuous cropping system is poor growth and reduced yield and quality. Overall, the polygon area formed by each index in the CK group is the smallest, and the polygon area formed by each index in the RSD group is higher than that in the CK group, indicating that the impact of RSD on the continuous cropping system is comprehensive and balanced. Figure 4 It can be seen that under the RSD1 treatment condition, the soil fertility in the pepper continuous cropping system was the highest; under the RSD2 treatment condition, the growth index and quality index of the pepper continuous cropping reached the maximum; under the RSD3 treatment condition, the incidence of pepper continuous cropping was the lowest. The effects of different organic material RSD treatments on the pepper continuous cropping system were different, but compared with the CK treatment group, they could achieve the effects of promoting growth, increasing yield, improving quality, and reducing disease. Correlation analysis of various indicators of pepper continuous cropping system under RSD treatment ( Figure 5) showed that there was a strong positive correlation (P<0.001) between soil fertility and photosynthetic characteristics (r=0.87) and yield indicators (r=0.69); the incidence rate was significantly negatively correlated with soil fertility (r=-0.54, P<0.05) and photosynthetic characteristics (r=-0.59, P<0.01).

[0112] 4. Discussion

[0113] Continuous cropping has become an important factor affecting crop growth. Long-term continuous cropping will reduce soil quality and is not conducive to the healthy growth of crops. The growth, incidence and yield of replanted crops are important indicators to measure whether different technical means can effectively alleviate continuous cropping problems. This study found that compared with CK, the RSD treatment increased the biomass of pepper roots and aboveground parts. The RSD treatment can significantly enhance the photosynthesis of peppers and improve photosynthetic efficiency. The RSD3 treatment had the best yield-increasing effect, significantly increasing yield by 23.65% compared with the CK treatment. The organic matter content of the soil under continuous cropping of peppers in this study was only 13.35 g kg -1 , low organic matter content and saturation point are the key factors restricting the formation of pepper yield. Therefore, the yield-increasing effect of RSD treatment may be attributed to the high carbon content of straw. It is worth noting that RSD treatment, regardless of the type of organic material used as raw material, can significantly reduce the incidence of continuous pepper. Recent studies have also found that RSD treatment can significantly reduce crop incidence and significantly increase yield. This result can be attributed to the production of abundant bactericidal substances such as acetic acid, butyric acid, hydrogen sulfide, ammonia, and reducing agents such as Fe by anaerobic microorganisms in the decomposition process of organic materials. 2+ and Mn 2+ . In addition, the organic acids produced by RSD treatment can significantly inhibit the activity of pathogens. Under continuous cropping conditions, the surge in the types and numbers of soil pathogens makes crops susceptible to infection by multiple pathogens, which is an important reason for the surge in the incidence of continuous cropping crops. Under the conditions of this experiment, the incidence of comprehensive soil-borne diseases of peppers in the CK group was 46.58%, and the incidence rate during RSD treatment was below 40%, with the lowest being only 29.51% (RSD3). This further confirms the broad-spectrum bactericidal effect of RSD treatment and its feasibility for field disease control.

[0114] Improving soil fertility is of great significance to increasing crop yields. This study found that compared with the CK treatment, RSD significantly increased soil pH, alkaline nitrogen, available potassium, and organic matter content, while the soil available phosphorus content was significantly reduced during RSD treatment. Previous studies have also found that RSD treatment can significantly increase the content of organic matter, alkaline nitrogen, and available potassium in the soil. The main reason for the increase in soil organic matter is the residue of a large amount of easily decomposable organic materials; the increase in organic matter leads to an increase in the soil carbon-nitrogen ratio, thereby stimulating microorganisms in the soil to mineralize organic nitrogen into inorganic nitrogen, which increases the content of alkaline nitrogen; the straw contains a large amount of potassium, which is decomposed and transformed by microorganisms, increasing the potassium content in the soil. At the same time, the dissolution of potassium-containing minerals by organic acids produced during RSD treatment can also significantly increase the available potassium content. The reduction in soil available phosphorus content may be due to the large-scale reproduction of microorganisms under sufficient carbon and nitrogen sources, forming a biological net fixation of phosphorus, which significantly reduces the available phosphorus content in the soil. Another possibility is that during the RSD treatment, high-valent iron is reduced, and insoluble iron phosphate can become effective phosphorus due to the reduction of iron. When the soil returns to aerobic state, the reduced iron is oxidized again, regenerating insoluble iron phosphate or forming iron oxides to wrap phosphorus, reducing the effectiveness of phosphorus. Therefore, the effect of RSD treatment on the content of available phosphorus may be the combined result of these two opposite processes. Comprehensive analysis found that compared with CK treatment, RSD treatment can significantly improve the soil fertility index, and soil fertility is extremely significantly positively correlated with pepper yield (P<0.001) and significantly negatively correlated with pepper incidence (P<0.05). Therefore, the improvement of soil fertility under RSD treatment is an important reason for the increase in pepper yield and the reduction in incidence.

[0115] RSD treatment significantly improved the fruit quality of continuously cropped peppers, and the VC content, soluble solid content, and crude protein content all increased. Previous studies have also found that the sugar-acid ratio, VC content, and soluble protein content of pepper fruits increased under RSD treatment. RSD treatment provides a suitable soil water and heat environment for crop growth, which is conducive to better accumulation of fruit nutrients. Correlation analysis found that quality indicators and photosynthetic characteristics were significantly positively correlated, and RSD treatment affected quality by enhancing crop photosynthesis. Photosynthesis is the basis for the formation of crop yield and quality. Plant photosynthetic carbon cycle and organic matter synthesis jointly promote the formation of crop quality.

[0116] Comprehensive analysis showed that under the RSD1 treatment, the soil fertility index in the pepper continuous cropping system was the largest; under the RSD2 treatment, the growth and quality indexes of the continuous pepper reached the maximum; under the RSD3 treatment, the incidence of the continuous pepper was the lowest. The effects of different organic material RSD treatments on the pepper continuous cropping system were different, which may be caused by the differences in soil microbial activity and functional diversity under different RSD treatments, which needs further verification. However, compared with the CK treatment group, the RSD treatments can achieve the effects of promoting growth, increasing yield, improving quality, and reducing disease, and have a synergistic effect in the formation of pepper yield and quality and improving soil fertility.

[0117] In summary, taking into account the growth indicators, photosynthetic indicators, yield quality indicators, and soil fertility indicators of continuously cropped peppers, under the conditions of this experiment, the RSD3 treatment using a mixture of pepper straw and rice straw as raw material performed the most balanced in promoting the growth of continuously cropped peppers, increasing yield and quality, and improving soil and fertility.

[0118] The description of the above embodiments is only used to understand the method and core idea of ​​the present invention. It should be pointed out that, for those skilled in the art, several improvements and modifications can be made to the present invention without departing from the principle of the present invention, and these improvements and modifications will also fall within the scope of protection of the claims of the present invention.

Claims

1. A RSD raw material, characterized in that The raw materials include pepper stalks.

2. The raw material according to claim 1, characterized in that The raw materials also include other plant straws except pepper straws.

3. The raw material according to claim 2, characterized in that The other plant straws include wheat straw, rice straw, corn straw, sorghum straw, peanut straw, soybean straw, potato straw, and sweet potato straw; preferably, the other plant straws are selected from rice straw.

4. The raw material according to claim 2, characterized in that The mass ratio of the pepper straw to other plant straws is 1:1-100:1; Preferably, the mass ratio of the pepper straw to other plant straws is 1:1-10:1; Preferably, the mass ratio of the pepper straw to other plant straws is 1:

1.

5. The raw material according to claim 1, characterized in that The raw materials also include soil fertilizer; Preferably, the soil fertilizer includes organic fertilizer, inorganic fertilizer, and biological fertilizer; Preferably, the organic fertilizer is derived from plants and / or animals; Preferably, the inorganic fertilizers include nitrogen fertilizer, phosphorus fertilizer and potassium fertilizer; Preferably, the biological fertilizer includes nitrogen-fixing bacterial fertilizer and phosphate-dissolving bacterial fertilizer.

6. A method for reducing the obstacles of pepper continuous cropping, characterized in that: The method comprises treating soil with the raw material according to any one of claims 1 to 5; Preferably, the usage of the raw material is 0.31-50 t·hm -2 ; Preferably, the amount of the raw material used is 5 to 15 t·hm -2 ; Preferably, the usage of the raw material is 15t·hm -2 ; Preferably, the soil temperature during treatment is 20-40°C; Preferably, the soil temperature during treatment is 25-35°C; Preferably, the soil treatment time is 14 to 45 days; Preferably, the treatment time of the treated soil is 30 days.

7. The method according to claim 6, characterized in that The method comprises treating soil with the raw material according to any one of claims 1 to 5, creating a strong reducing environment for the soil, and drying the soil; Preferably, a strong soil reduction environment can be created by irrigating the soil to saturation, covering with plastic film, or flooding to block gas exchange with the atmosphere; Preferably, the drying time is 5 to 20 days; Preferably, the drying time is 15 days.

8. The method according to claim 6, characterized in that The method comprises spreading 15 t·hm2 of fertilizer in the pepper continuous cropping area -2 The raw material according to any one of claims 1 to 5 is mixed with cultivated soil, covered with film, and the soil is irrigated under the film to saturation, and treated for 30 days, during which the soil temperature is 25 to 35° C., punched with holes, and aired for 15 days.

9. The method according to claim 6, characterized in that The method also includes using it sequentially, simultaneously or crosswise with other methods for preventing and controlling continuous cropping disorders; Preferably, the other methods for preventing and controlling continuous cropping obstacles include physical measures, chemical measures, biological measures, application of resistant varieties and / or grafting of resistant varieties; Preferably, the physical measures include high temperature greenhouse, crop rotation, intercropping, relay cropping, irrigation and salt washing, short-term flooding, and planting of filler crops; Preferably, the chemical measures include soil chemical fumigation and lime application; Preferably, the biological measures include applying microbial fertilizer or biological organic fertilizer, and biological antagonistic bacteria.

10. Any of the following applications: (1) Use of the raw material according to any one of claims 1 to 5 in alleviating the obstacles of pepper continuous cropping; (2) Use of the raw material according to any one of claims 1 to 5 in promoting the growth of peppers; (3) Use of the raw material according to any one of claims 1 to 5 in reducing the incidence of pepper; (4) Use of the raw material according to any one of claims 1 to 5 in promoting photosynthesis of pepper; (5) Use of the raw material according to any one of claims 1 to 5 in increasing pepper yield; (6) Use of the raw material according to any one of claims 1 to 5 in improving the quality of peppers; (7) Use of the raw material according to any one of claims 1 to 5 in improving soil fertility.

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