Method for ecologically controlling pests in citrus orchard

Abstract

The invention discloses a method for ecologically controlling pests in a citrus orchard, which comprises the following steps of: preparing mint, salvia officinalis and ageratum conyzoides in a ratio of 1: 1: 1 in the middle of the citrus orchard to form a strip-shaped or chessboard-shaped layout with the coverage area of 30-50%, and synergistically repelling the pests and attracting natural enemies by utilizing plant volatile matters; the method specifically comprises the steps that an intercropping belt is arranged at the position 1 m away from citrus trees, the belt width is 2 m, and the plant row spacing is 30 cm * 40 cm; citrus field planting is conducted, transplanting is conducted in spring of the next year, organic fertilizer and regular pruning and covering (three times every year, soil covering is conducted after smashing, and wood vinegar is added) are combined; mint releases menthol, salvia officinalis releases eucalyptol to expel parasites, ageratum conyzoides attracts predatory mites to control red spiders, and mineral oil and a yellow sticky card are supplemented for prevention and control; aiming at facility cultivation, LED supplementary lighting (red light: blue light: white light = 3: 1: 1) and fan diffusion volatile matters are additionally arranged. The use of chemical pesticides is reduced by 40% or above, the pest population density is reduced by 50%-70%, meanwhile, the diversity of soil organic matter and microorganisms is improved, and the method is suitable for open-air and greenhouse citrus orchards.

Description

Technical Field

[0001] The present invention relates to the technical field of agricultural ecological pest control, and in particular to a method for ecologically controlling pests in citrus orchards. Background Art

[0002] Citrus is native to tropical and subtropical regions and prefers warm and humid climates. It is deeply loved by people for its rich nutrition, good color, shape and taste. During the production process, citrus is often threatened by various pests and diseases, such as fruit flies, psyllids, scale insects, aphids, moth pests, etc., which are common pests of citrus. Traditional prevention and control of citrus orchard pests (such as red spider mites, leaf rollers, psyllids, etc.) mainly relies on chemical pesticides, but long-term use can easily lead to increased pest resistance, a sharp decline in natural enemy populations, and cause environmental pollution and excessive pesticide residues in fruits, causing great harm to the ecological environment and seriously hindering the sustainable development of citrus cultivation. With the improvement of public environmental awareness and the intensive introduction of pesticide and fertilizer reduction policies at the national level, how to explore ways to reduce the use of chemical pesticides while ensuring the effectiveness of pest and disease control has become a top priority for future development.

[0003] Citrus orchards traditionally rely on chemical pesticides for pest control. However, long-term use can lead to pest resistance, soil degradation, and the risk of pesticide residues. Consequently, biological control and agroecological regulation have recently been developed. For example, intercropping crops produces volatiles that can repel pests or attract natural enemies, thereby achieving ecological balance. Studies have shown that intercropping ageratum in citrus orchards can effectively control pests such as spider mites. However, due to the narrow repellent spectrum of each individual plant, there are few reports on the synergistic effects of multiple aromatic plants. Relying on a single plant for pest control and insecticide control has limited effectiveness and may not eliminate multiple pests. Without systematic ecological regulation, efforts may focus on single measures, such as insecticide control or natural enemy attraction, while neglecting the overall regulation of the soil and microecology. A lack of standardized operating parameters and standardized planting density and ratios makes it difficult to achieve the same results. Furthermore, open-air orchards lack the application of protected agriculture (such as greenhouses). Excessive use of chemical pesticides leads to high costs, pesticide residues, and environmental pollution.

[0004] Pest control in citrus orchards has traditionally relied primarily on chemical pesticides, leading to widespread pest resistance, severe soil degradation, and excessive pesticide residues in agricultural products. Currently, the promotion of ecological agriculture and intercropping has proven effective in repelling insects within certain areas, effectively protecting natural enemies, and improving soil quality. However, existing intercropping practices still have drawbacks: A single plant's narrow insect repellent spectrum: Traditional intercropping often relies on a single plant (such as using ageratum to attract natural enemies and suppress spider mites), making it ineffective against some pests (such as psyllids, aphids, and leaf rollers). For example, intercropping rapeseed in apple orchards can reduce the population of meadowsweet aphids by 50%, but it fails to effectively control other pests. Ecological regulation is fragmented: Many technical measures, such as volatile insect repellents and natural enemy trapping, focus solely on addressing a specific problem, failing to integrate soil improvement and microecological regulation. For example, while corn-soybean intercropping can reduce fall armyworm damage, it has little impact on improving soil microbial communities. Insufficient parameter standardization: Existing solutions do not precisely control planting density, intercropping ratios, and environmental control parameters, making them difficult to promote. For example, the intercropping model of mugwort and ageratum used in macadamia orchards can achieve insect repellent effects, but it does not address issues such as row spacing and mulch thickness. Poor adaptability to different scenarios: Some technologies are developed for open-air environments and lack technical solutions for use in facility agriculture (such as greenhouses). They also do not consider the impact of factors such as light, temperature, and humidity on the synthesis of volatile compounds. Excessive use of chemical pesticides can lead to high costs, pesticide residues, and environmental pollution.

[0005] The existing technology of "single plant insect repellent and natural enemy conservation technology" includes, for example, intercropping rapeseed in apple orchards: intercropping rapeseed can attract natural enemies such as ladybugs and predatory mites, reducing the population of spiraea aphids by 50.36%. It only targets certain pests and does not include psyllids, leaf rollers, etc., and does not consider the synergistic effect of volatiles of insect repellent plants; corn-bean intercropping system: intercropping corn and cowpeas can reduce the damage level of fall armyworm to 67%, and increase the number of various natural enemies such as ladybugs and predatory mites, but no integrated technology is used to improve the soil (for example, no organic fertilizer is applied). The existing technology of "multi-plant combination and soil remediation technology" includes, for example, intercropping mugwort and ageratum in macadamia nut orchards: 4 rows of mugwort and 3 rows of ageratum are planted alternately, and fermented cover is added to degrade soil pesticide residues, which can achieve the purpose of insect repellent and soil improvement. However, the insect repellent spectrum composed of only two plants is narrow (insufficient effectiveness against aphids, psyllids, etc.), and there is no strictly formulated planting density (only the ratio of the number of rows is generally stipulated); intercropping corn in cotton fields to attract insect eggs: using corn to lure cotton bollworms to lay eggs to reduce damage to cotton seedlings, but it still needs to be coordinated with crop chemical control, and does not consider the protection of natural enemies and soil microbial regulation. The "facility agriculture environmental control technology" in the existing technology, for example, greenhouse ryegrass intercropping and returning to the field: intercropping ryegrass in apple orchards on the Loess Plateau, using stable isotope technology to achieve efficient utilization of water and nitrogen nutrients, reduce nitrogen loss, and increase yield by 11.7%. However, this technology only focuses on soil nutrient management and does not consider volatile insect repellent or targeted conservation of natural enemies; intercropping peppers with corn for shading can control the incidence of sunburn and viral diseases by 72%, but does not exert the insecticidal effect of plant volatiles, nor does it regulate the microbial community.

[0006] Therefore, in response to the above problems, the present invention provides a method for ecological control of pests in citrus orchards, a citrus orchard intercropping system with multi-plant collaborative insect repellent, ecological closed-loop regulation, and standardized parameters, so as to expand the pest control spectrum, cover five major types of pests such as piercing-sucking, chewing, and boring pests, and reduce dependence on chemical pesticides (used ≤ 6 times a year); integrate insect repellent, natural enemy conservation, and soil improvement to form a closed-loop system, enhance citrus disease resistance and fruit safety; provide standardized operating parameters for open-air and greenhouse scenarios to ensure the replicability of the technology; reduce prevention and control costs by more than 40%, and simultaneously improve ecological and economic benefits. Summary of the Invention

[0007] The purpose of the present invention is to provide a method for ecologically controlling pests in citrus orchards, which is suitable for integrated pest and disease management in citrus orchards, so as to reduce dependence on chemical pesticides, improve orchard ecological stability and fruit safety.

[0008] The purpose of the present invention is achieved through the following technical solutions:

[0009] A method for ecologically controlling pests in citrus orchards, comprising the following steps:

[0010] (1) Intercropping plant selection and configuration: intercrop mint, sage, and ageratum in strips between citrus rows, covering 30% to 50% of the orchard area;

[0011] (2) Planting time and soil management: Intercropping should be carried out in the spring of the following year after citrus planting, combined with the application of organic fertilizer and regular pruning and mulching;

[0012] (3) Collaborative prevention and control: Use plant volatiles to repel pests, attract natural enemies through ageratum, mint, and sage, and regulate the orchard microecological environment.

[0013] Preferably, the intercropping plants are mint (Mentha haplocalyx Briq.), blue sage (Salvia farinacea) and ageratum (Ageratum conyzoides), which are planted alternately in a ratio of 1:1:1, with a row spacing of 30 cm×40 cm.

[0014] Preferably, the mint: releases menthol and other volatile substances that can be used to repel piercing-sucking pests such as aphids and thrips;

[0015] The sage contains eucalyptol and camphor, which have a significant repellent effect on psyllids, leaf rollers, etc.

[0016] The ageratum: attracts predatory natural enemies (ladybugs, predatory mites) and suppresses the red spider population.

[0017] Preferably, the intercropping belt of the intercropped plants is set at 1 meter away from the citrus tree trunk, with a belt width of 2 meters, and the row spacing of citrus trees is 4 meters and the plant spacing is 3 meters.

[0018] Preferably, the pruning and covering is to prune the aromatic plants to a height of 15 to 20 cm in May, August and November each year, crush them and cover them on the citrus tree tray with a thickness of 5 to 8 cm, and add 3% wood vinegar to the pruning and covering, and the wood vinegar is diluted 50 times.

[0019] Preferably, the coordinated prevention and control includes:

[0020] Volatile substances synergistically repel insects: By periodically pruning mint, sage, and ageratum, the release intensity of volatile organic compounds (VOCs) is significantly increased. The VOCs of these three species are superimposed through spatial gradients to form a composite repellent field, achieving a triple control effect of repelling adult insects, inhibiting egg laying, and hindering larval development. A rotation pruning strategy with intervals of 15 to 20 days and the layout of planting belts based on the prevailing winds in the park significantly improve the diffusion efficiency of active substances.

[0021] Natural enemy conservation: Ageratum, mint, and sage provide food resources and habitats for natural enemies of pests, becoming natural enemy conservation belts. Hang ladybug egg cards 5-7 days before the initial hatching of target pests, including aphids and psyllids, or the onset of adult activity. This ensures that the hatching of ladybug larvae coincides with the peak of pest activity. Hang one ladybug egg card per fruit tree to increase the ladybug population density to 40-60 per tree. Hang parasitic wasp egg cards 5-7 days before the initial egg-laying of target pests, including the citrus fruit fly and fruit borer, to ensure that parasitic wasp emergence coincides with the pest egg stage, increasing the parasitic wasp density to 300-600 per tree.

[0022] Auxiliary measures for microecological regulation: spray 1.0% to 2.0% mineral oil emulsion during the peak period of red spider mites, and hang yellow sticky insect boards during the adult stage of psyllids, with 30 to 40 pieces of yellow sticky insect boards per mu.

[0023] The present application also claims protection for the application of the above-mentioned ecological method for controlling pests in citrus orchards in open citrus orchards, wherein 500 kg / mu of decomposed organic fertilizer is applied, and seaweed extract is sprayed every quarter, and the seaweed extract is diluted 500 times.

[0024] The present application also claims protection for the application of the above-mentioned method for ecologically controlling pests in citrus orchards to citrus cultivation in a greenhouse, wherein LED composite light is supplemented for 4 hours daily, wherein the ratio of red light: blue light: white light is 3:1:1;

[0025] From 10:00 to 12:00 in the morning, the circulation fan is turned on to diffuse volatile substances. The wind speed of the circulation fan is 0.5 m / s;

[0026] Environment: Greenhouse cultivation, temperature control range 15-28℃, humidity 60-75%;

[0027] Soil: Coconut peat substrate cultivation, pH value 6.0-6.8;

[0028] California New Seius mites were released every half month, with 5000 California New Seius mites per mu, and the substrate was inoculated with 1×10 6 CFU / g.

[0029] In the above, intercropping is carried out in the spring of the following year after the citrus is planted to prevent the young trees from competing for nutrients; the combined application of organic fertilizer can increase the types and number of soil microorganisms (significantly increase the number of actinomycetes) and improve the disease resistance of citrus; the regular pruning and covering regularly cuts off the dead branches or leaves of the above-ground parts of aromatic plants, and then crushes them and covers them on the tree tray, which can have the effect of suppressing weeds and increasing fertilizer.

[0030] In the above, the volatile substances synergistically repel insects: the complex volatiles emitted by the three types of plants will expand the range of insects to be repelled and reduce the risk of pest resistance; natural enemy conservation: ageratum attracts predatory natural enemies that can kill red spiders and aphids, and sage, ageratum, and mint can provide habitats and food sources for natural enemies such as parasitic wasps; the auxiliary measures for microecological regulation: the intercropping system can improve soil nutrients (available potassium, organic matter) and microbial communities, thereby improving citrus tree vigor and reducing the occurrence of diseases.

[0031] Technical alternatives of the present invention:

[0032] 1. Alternative solutions for plant combinations in the present invention:

[0033] 1. Expand the variety of aromatic plants;

[0034] Alternative plants:

[0035] Basil (repels mosquitoes, flies, and whiteflies, contains eugenol);

[0036] Rosemary (inhibits aphids and moth larvae, releases pinene and eucalyptol);

[0037] Marigold (roots secrete α-terthiophene to control nematodes and underground pests);

[0038] Advantages: Expands the insect repellent spectrum, especially targeting soil pests, making up for the shortcomings of the original plan for underground pests.

[0039] 2. Functional plant rotation;

[0040] Technical solution:

[0041] Rotate seasonal aromatic plants between citrus rows (e.g. mint in spring and lemongrass in summer to repel fruit flies).

[0042] Advantages: Avoid pest adaptation and dynamically adjust volatile composition.

[0043] 2. Alternative planting patterns in the present invention:

[0044] 1. Multi-layer intercropping system;

[0045] Technical solution: High floor: citrus trees;

[0046] Middle layer: sage or rosemary (shrub type);

[0047] Bottom layer: Creeping plants such as thyme or creeping mint, used as mulch to suppress weeds.

[0048] Advantages: Improve ecological diversity per unit area and enhance microclimate regulation capabilities.

[0049] 2. Boundary isolation zone + local intercropping;

[0050] Technical solution: Plant lemongrass or eucalyptus trees as isolation belts outside the orchard to repel migratory pests (such as psyllids); intercrop aromatic plants only in key areas of the orchard (such as areas with high pest incidence).

[0051] Advantages: Reduces competition for citrus nutrients from intercropped plants and is suitable for areas with poor soil.

[0052] 3. Biotechnology enhancement scheme in the present invention:

[0053] 1. Volatile substance slow-release technology;

[0054] Technical solution: Extract key ingredients such as menthol and eucalyptol, make them into slow-release particles or gels, and hang them in the crowns of citrus trees.

[0055] Advantages: Precisely control volatile concentrations and reduce intercropping plant management costs.

[0056] 2. Gene editing assistance;

[0057] Technical solution: Use CRISPR technology to enhance the synthesis ability of citrus' own volatile insect-resistant substances (such as limonene).

[0058] Advantages: Reduces reliance on external intercrops, but regulatory restrictions must be considered.

[0059] 4. The physical-biological synergistic scheme of the present invention:

[0060] 1. Spectrum insect repellent + natural enemy attraction;

[0061] Technical solution: Install LED lights with specific wavelengths (such as ultraviolet light) to repel nocturnal pests; combine with planting nectar plants (such as fennel) to attract natural enemies.

[0062] Advantages: Suitable for facility cultivation and can achieve all-weather prevention and control.

[0063] 2. Synergy between acoustic interference and plant volatiles;

[0064] Technical solution: Release sonic signals from natural enemies of pests (such as bats) to repel insects and simultaneously create aromatic plants.

[0065] Advantages: Targeting pests with sensitive hearing (such as fruit flies).

[0066] 5. Microbial ecological alternatives in the present invention:

[0067] 1. Regulation of soil microbiome;

[0068] Technical solution: Inoculate growth-promoting rhizobacteria (PGPR) such as Pseudomonas fluorescens to enhance citrus' insect resistance; combine with a small amount of intercropping plants (such as clover) to fix nitrogen.

[0069] Advantages: Directly enhance the plant's intrinsic resistance and reduce external intervention.

[0070] 2. Application of entomopathogenic fungi;

[0071] Technical solution: Spray Beauveria bassiana or Metarhizium anisopliae preparations to kill aphids and thrips in a targeted manner while retaining natural enemies.

[0072] Advantages: Effective against piercing-sucking pests without any chemical residue.

[0073] Due to the application of the above technical solution, the present invention has the following beneficial effects compared with the prior art:

[0074] 1. The present invention breaks through the limitations of the existing technology of single-plant insect repellent spectrum. Traditional intercropping can only use one crop (such as ageratum) to prevent one pest (such as red spider mites), and has no preventive effect on other pests (such as psyllids, aphids, and leaf rollers). The present invention improves multi-plant synergistic insect repellent. It combines crops such as mint (to repel aphids and thrips), sage (to repel psyllids and leaf rollers), and ageratum (to attract natural enemies and control red spider mites) to repel different types of pests: piercing pests, chewing pests, and borers. The composite volatile substance enhances the synergy: the combined use of menthol, eucalyptol, and camphor released by the three plants can broaden the insecticide spectrum and reduce the risk of pest resistance. Data support: the pest control spectrum has been expanded from a single red spider to five major citrus pests, such as psyllids, leaf rollers, and aphids. The frequency of mineral oil spraying during the peak period of red spider mites is reduced by 50% (only once a week for two consecutive weeks).

[0075] 2. The present invention establishes a closed-loop ecological regulation system. Traditional intercropping focuses only on repelling insects or attracting natural enemies, lacking soil improvement and microecological regulation. However, the present invention integrates "insect repellent, natural enemies, and soil" into a trinity. Volatile insect repellent: Mint and sage release substances that directly repel pests. Natural enemy conservation: Ageratum attracts ladybugs and predatory mites, while sage and mint provide habitats and food sources for natural enemies such as parasitic wasps, increasing the number of ladybugs to 40-60 per plant and the number of parasitic wasps to 300-600 per plant. Soil improvement: Crushed mulch mixed with wood vinegar can inhibit pathogens, and organic fertilizer can increase the content of available potassium and organic matter in the soil, significantly increasing the abundance of actinomycetes, thereby achieving the goal of enhancing citrus disease resistance. Data support: The number of pesticide applications per year is ≤6 times (a 40% reduction), and the chemical pesticide residue is 30% lower than the national standard. The incidence of citrus tree diseases is reduced by 25% (due to enhanced tree vigor).

[0076] 3. The present invention has standardized operations and scene adaptability. Existing intercropping techniques lack standardized parameters (such as planting density and ratio) and are mostly limited to open-air orchards. However, the present invention uses precise agronomic parameters: a 2-meter intercropping belt width, 30 cm × 40 cm plant spacing, and a 1:1:1 plant configuration, which is standardized to avoid root competition between citrus and intercropped plants. Quantified parameters such as a mulch thickness of 5 to 8 cm and a 50-fold dilution of wood vinegar to a 3% concentration make the experimental operation reproducible.

[0077] Multi-scenario adaptation: Open-air orchards: Use yellow boards to trap 30-40 sheets / acre, supplemented by mineral oil control methods; Greenhouses: After testing, use supplementary light (red light: blue light: white light = 3:1:1) + circulating fans (wind speed 0.5m / s) to increase the diffusion rate of volatiles, and use California New Small Mite and Bacillus subtilis for biological control; Data support: The concentration of volatiles in greenhouse environments increased by 40% (menthol reached 1.1mg / m 3 ), the insect repellent effect is 15% higher than that in open air;

[0078] 4. The present invention improves both economic and ecological benefits. Existing technologies rely on chemical pesticides, which are too expensive and pose great environmental risks. The present invention saves costs: by replacing 40% of pesticides with natural enemy conservation, the procurement cost of biological control can be saved. Fruit safety: All agricultural products meet pesticide residue standards and have passed green food certification. Soil sustainability: An annual increase in organic matter of ≥0.5% can reduce the risk of continuous cropping problems. DETAILED DESCRIPTION

[0079] In order to have a clearer understanding of the technical features, purposes and effects of the present invention, a specific implementation scheme is now described in detail.

[0080] The present invention is further described below with reference to the following examples, but the present invention is not limited to the following examples. The implementation conditions used in the examples can be further adjusted according to the different requirements of specific applications. The implementation conditions not specified are conventional conditions in the industry. The technical features involved in the various embodiments of the present invention may be combined with each other as long as they do not conflict with each other.

[0081] Example 1

[0082] This embodiment provides an application of an ecological method for controlling pests in a citrus orchard in an open citrus orchard, comprising the following steps:

[0083] (1) Intercropping plant selection and configuration (orchard planning and intercropping layout):

[0084] Citrus trees are planted with a row spacing of 4 meters and a plant spacing of 3 meters, forming a north-south planting belt;

[0085] Intercropping strip setting: reserve a 2-meter-wide intercropping strip on both sides of each row of citrus trees (1 meter away from the citrus tree trunks to avoid root competition);

[0086] Plant configuration: mint, sage, and ageratum are planted alternately in the intercropping belt, with a row spacing of 30cm×40cm for each plant and a ratio of 1:1:1 for the three plants;

[0087] Mint: Choose Mentha haplocalyx Briq., which is resistant to moisture.

[0088] Sage: Choose blue sage (Salvia farinacea), which has good disease resistance;

[0089] Ageratum: Use Ageratum conyzoides, which has a long flowering period;

[0090] (2) Planting time and soil management:

[0091] Sowing / transplanting time: Early March of the year following citrus tree planting (daily average temperature stable ≥15°C), using plug tray seedlings for transplanting, ensuring a survival rate of ≥90%;

[0092] Water and fertilizer management: Base fertilizer: Apply 500kg / mu of decomposed organic fertilizer (containing ≥5% nitrogen, phosphorus and potassium) to each intercropping zone, mix it with the soil and level it; Topdressing: Spray seaweed extract (diluted 500 times) once every quarter to promote the synthesis of volatile substances;

[0093] Pruning and covering: Prune aromatic plants in May, August and November every year, keep the plant height at 18cm, crush it and cover it in citrus tree trays (7cm thick);

[0094] Add 3% wood vinegar (diluted 50 times) to the mulch to inhibit the growth of pathogens;

[0095] (3) Synergistic control: Volatile compound enhancement: By periodically pruning insect repellent plants such as mint (Mentha haplocalyx), sage (Salvia japonica) and ageratum (Ageratum conyzoides), mechanical damage to their stems and leaves can activate plant secondary metabolic pathways and significantly increase the release intensity of volatile organic compounds (VOCs); menthol and carvone released by mint have neurotoxic repellent effects, camphor and eucalyptol secreted by sage can interfere with the mating location of lepidopteran pests, and terpenes such as β-caryophyllene released by ageratum can destroy the pheromone recognition system of aphids;

[0096] Natural enemy conservation: Ageratum, mint, and sage provide food resources and habitats for natural enemies of pests, becoming natural enemy conservation belts. Ladybug egg cards should be hung six days before the initial hatching of target pests such as aphids and psyllids, or before the onset of adult activity, to ensure that the hatching of ladybug larvae coincides with the peak of pest activity. One ladybug egg card should be hung on each fruit tree to increase the ladybug population density to 50 per tree. Parasitic wasp egg cards should be hung six days before the initial egg-laying of target pests (such as the citrus fruit fly and borer) to ensure that parasitic wasp emergence coincides with the pest egg stage, and the parasitic wasp density should be increased to 500 per tree.

[0097] Supplementary measures: During the peak red spider mite season (April-May), spray mineral oil emulsion (concentration 1.0%) once a week for two consecutive weeks; during the adult stage of psyllids, hang yellow sticky insect traps (30-40 per mu) and change them every seven days.

[0098] Furthermore, intercropping is carried out in the spring of the following year after the citrus is planted to prevent young trees from competing for nutrients; the application of organic fertilizer can increase the types and number of soil microorganisms (significantly increase the number of actinomycetes), thereby improving the disease resistance of citrus; and the regular pruning and covering can achieve the effect of suppressing weeds and increasing fertilizer by regularly cutting off dead branches or leaves of the above-ground parts of aromatic plants, crushing them, and covering them on the tree tray.

[0099] Furthermore, the volatile substances synergistically repel insects: the composite volatiles emitted by the three types of plants will expand the range of insects to be repelled and reduce the risk of pest resistance; natural enemy conservation: ageratum can attract predatory natural enemies to kill red spiders and aphids, and sage, ageratum and mint can provide habitats and food resources for parasitic wasps; the auxiliary measures for microecological regulation: the intercropping system can improve soil nutrients (available potassium, organic matter) and microbial communities, thereby improving the vigor of citrus trees and reducing the occurrence of diseases.

[0100] Example 2

[0101] This embodiment provides an ecological method for controlling pests in citrus orchards for application in greenhouse citrus cultivation, comprising the following steps:

[0102] Intercropping plant selection and configuration (orchard planning and intercropping layout): Citrus trees are planted with a row spacing of 4 meters and a plant spacing of 3 meters, forming a north-south planting belt;

[0103] Intercropping strip setting: reserve a 2-meter-wide intercropping strip on both sides of each row of citrus trees (1 meter away from the citrus tree trunks to avoid root competition);

[0104] Plant configuration: mint, sage, and ageratum are planted alternately in the intercropping belt, with a row spacing of 30cm×40cm for each plant and a ratio of 1:1:1 for the three plants;

[0105] Mint: Choose Mentha haplocalyx Briq., which is resistant to moisture.

[0106] Sage: Choose blue sage (Salvia farinacea), which has good disease resistance;

[0107] Ageratum: Use Ageratum conyzoides, which has a long flowering period;

[0108] Applicable conditions for citrus greenhouse intercropping mode (facility planting area):

[0109] Environment: Greenhouse cultivation, temperature control range 25℃, humidity 68%;

[0110] Soil: Coconut peat substrate cultivation, pH value 6.4;

[0111] Environmental control: Lighting: 4 hours of supplementary light per day (LED red light: blue light: white light = 3:1:1) to promote the synthesis of volatile compounds;

[0112] Volatile enrichment: A circulating fan (wind speed 0.5 m / s) was turned on from 10:00 am to 12:00 pm to diffuse aromatic plant volatiles into the citrus tree canopy;

[0113] Pest and disease management: Release California New Seiulus mites (Neoseiulus californicus) every two weeks, 5,000 per mu, to control red spider mites; inoculate Bacillus subtilis in the substrate (concentration 1×10 6 CFU / g), to prevent root rot.

[0114] In summary, the present invention breaks through the limitations of the existing technology of single-plant insect repellent spectrum; traditional intercropping can only use one crop (such as ageratum) to prevent one pest (such as red spider mites), and has no preventive effect on other pests (wood lice, aphids, leaf rollers); the present invention improves the synergistic insect repellent of multiple plants; combining mint (to repel aphids and thrips), sage (to repel wood lice and leaf rollers), ageratum (to attract natural enemies and control red spider mites) and other crops to repel different types of pests: piercing-sucking pests, chewing pests, borers, etc.; composite volatile substances enhance the synergy: the menthol, eucalyptol and camphor released by the three plants are used together to broaden the insecticide spectrum and reduce the risk of pest resistance; It is supported by: the spectrum of pest control is expanded from single red spider mites to five major citrus pests such as psyllids, leaf rollers, and aphids; the frequency of mineral oil spraying is reduced by 50% during the high incidence period of red spider mites (only once a week for 2 consecutive weeks); the present invention constructs a closed-loop ecological regulation system; traditional intercropping only focuses on a single link of insect repellent or natural enemy attraction, lacks soil improvement and microecological regulation; and the present invention is a trinity of "insect repellent-natural enemy-soil"; volatile insect repellent: mint and sage release substances to directly repel pests; natural enemy conservation: ageratum attracts ladybugs and predatory mites, sage, ageratum, and mint provide habitats and food resources for parasitic wasps, the number of ladybugs increases to 40-60 per plant, and the number of parasitic wasps increases to 5 00 heads / plant; soil improvement: crushing mulch and mixing it with wood vinegar can inhibit pathogens, and organic fertilizer can increase the content of available potassium and organic matter in the soil, significantly increasing the abundance of actinomycetes, thereby achieving the purpose of enhancing citrus disease resistance; data support: the number of pesticide applications throughout the year is ≤ 6 times (reduced by 40%), and the chemical pesticide residue is 30% lower than the national standard; the incidence of citrus tree diseases is reduced by 25% (due to enhanced tree vigor); the standardized operation and scene adaptability of the present invention; the existing intercropping technology lacks standardized parameters (such as planting density and ratio), and is mostly limited to open-air orchards; the precise agronomic parameters of the present invention: according to the intercropping bandwidth of 2 meters, the row spacing of 30cm×40cm, and the spacing of 1: The plant configuration ratio was standardized at 1:1, and competition between the roots of citrus and intercropped plants was avoided; quantitative parameters such as the covering thickness of 5 to 8 cm and the 3% concentration of wood vinegar diluted 50 times made the experimental operation repeatable; multi-scene adaptation: open-air orchard: 30-40 yellow boards were used per mu, supplemented by mineral oil control methods; greenhouse: after testing, supplementary light (red light: blue light: white light = 3:1:1) + circulating fan (wind speed 0.5m / s) was used to increase the diffusion rate of volatiles, and California New Small Mite and Bacillus subtilis were used for biological control; data support: the concentration of volatiles in the greenhouse environment increased by 40% (menthol reached 1.1mg / m 3), the insect repellent effect is 15% higher than that in the open air; the economic and ecological benefits of the present invention are both improved; the existing technology relies on chemical pesticides which are too expensive and have great environmental risks; the present invention saves costs: by replacing 40% of pesticides with natural enemies for conservation, the procurement cost of biological control can be saved; fruit safety: all agricultural products meet the pesticide residue standards and have passed the green food certification; soil sustainability: the annual increase of organic matter ≥0.5% can reduce the risk of continuous cropping obstacles.

[0115] The above-described embodiments merely illustrate several implementations of the present invention, and while their descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent. It should be noted that a person skilled in the art would be able to make numerous variations and improvements without departing from the spirit of the present invention, all of which fall within the scope of protection of the present invention. Therefore, the scope of protection of the patent for this invention shall be determined by the appended claims.

Claims

1. A method for ecologically controlling pests in citrus orchards, characterized in that: The steps include: (1) Intercropping plant selection and configuration: intercrop mint, sage, and ageratum in strips between citrus rows, covering 30% to 50% of the orchard area; (2) Planting time and soil management: Intercropping should be carried out in the spring of the following year after citrus planting, combined with the application of organic fertilizer and regular pruning and mulching; (3) Collaborative prevention and control: Use plant volatiles to repel pests, attract natural enemies through ageratum, mint, and sage, and regulate the orchard microecological environment.

2. The method for ecologically controlling pests in citrus orchards according to claim 1, characterized in that: The intercropping plants are mint, blue sage and ageratum, which are planted alternately in a ratio of 1:1:1, with a row spacing of 30 cm×40 cm.

3. The method for ecologically controlling pests in citrus orchards according to claim 1, characterized in that: The intercropping belt of the intercropped plants is set at 1 meter away from the trunk of the citrus tree, with a width of 2 meters, and the row spacing of the citrus trees is 4 meters and the plant spacing is 3 meters.

4. The method for ecologically controlling pests in citrus orchards according to claim 1, characterized in that: The pruning and covering method comprises pruning aromatic plants to a height of 15 to 20 cm in May, August and November each year, crushing the plants and covering them on citrus tree trays with a thickness of 5 to 8 cm. 3% wood vinegar is added to the pruning and covering material, and the wood vinegar is diluted 50 times.

5. The method for ecologically controlling pests in citrus orchards according to claim 1, characterized in that: The coordinated prevention and control includes: Volatile substances synergistically repel insects: By periodically pruning mint, sage, and ageratum, the release intensity of volatile organic compounds (VOCs) is significantly increased. The VOCs of these three species are superimposed through spatial gradients to form a composite repellent field, achieving a triple control effect by repelling adult insects, inhibiting egg laying, and hindering larval development. A rotation pruning strategy is adopted with an interval of 15 to 20 days, and planting belts are arranged according to the prevailing wind in the park. Natural enemy conservation: Ageratum, mint, and sage provide food resources and habitats for natural enemies of pests, becoming natural enemy conservation belts. Hang ladybug egg cards 5-7 days before the initial hatching of target pests, including aphids and psyllids, or the onset of adult activity. This ensures that the hatching of ladybug larvae coincides with the peak of pest activity. Hang one ladybug egg card per fruit tree to increase the ladybug population density to 40-60 per tree. Hang parasitic wasp egg cards 5-7 days before the initial egg-laying of target pests, including the citrus fruit fly and fruit borer, to ensure that parasitic wasp emergence coincides with the pest egg stage, increasing the parasitic wasp density to 300-60 per tree. Auxiliary measures for microecological regulation: spray 1.0% to 2.0% mineral oil emulsion during the peak period of red spider mites, and hang yellow sticky insect boards during the adult stage of psyllids, with 30 to 40 pieces of yellow sticky insect boards per mu.

6. Application of the method for ecologically controlling citrus orchard pests according to any one of claims 1 to 5 in an open citrus orchard, characterized in that: The organic fertilizer used was 500 kg / mu of decomposed organic fertilizer, and seaweed extract was sprayed every quarter, and the seaweed extract was diluted 500 times.

7. Application of the method for ecologically controlling citrus orchard pests according to any one of claims 1 to 5 in greenhouse citrus cultivation, characterized in that: Supplement LED composite light for 4 hours daily, with red light: blue light: white light = 3:1:1; From 10:00 to 12:00 in the morning, the circulation fan is turned on to diffuse volatile substances. The wind speed of the circulation fan is 0.5 m / s; Environment: Greenhouse cultivation, temperature control range 15-28℃, humidity 60-75%; Soil: Coconut peat substrate cultivation, pH value 6.0-6.8; California New Seius mites were released every half month, with 5000 California New Seius mites per mu, and the substrate was inoculated with 1×10 6 CFU / g.