A rice-wheat rotation farmland ecosystem and cross-season pest control method based on angelica-camellia intercropping enemy containment zone

Abstract

This invention discloses a rice-wheat rotation farmland ecosystem based on an intercropping natural enemy conservation zone of Angelica sinensis and Osmanthus fragrans, and a cross-seasonal pest control method. The method involves planting Osmanthus fragrans trees at 3-5 meter intervals along field ridges, with Angelica sinensis interspersed among them, thus constructing a perennial natural enemy conservation zone. During the flowering periods of Angelica sinensis (May-June) and Osmanthus fragrans (September-October), volatile compounds are released, providing nectar and pollen to attract natural enemies such as ladybugs, lacewings, hoverflies, and parasitic wasps to colonize and proliferate. These natural enemy populations naturally migrate into the farmland during the wheat and rice seasons to control pests such as wheat aphids, rice planthoppers, and rice stem borers, with significant control effects and reducing pesticide application by 1-2 times. This perennial system is easy to manage and can generate economic benefits from the harvest of Angelica sinensis and Osmanthus fragrans, providing a technical approach for green agriculture in rice-wheat rotation areas.

Description

Technical Field

[0001] This invention relates to the field of ecological management of agricultural pests, specifically to a method for cultivating natural enemy insects using a combination of functional plants, and more particularly to an intercropping method using the perennial Chinese medicinal herb Angelica sinensis and the woody plant Osmanthus fragrans on field ridges. Background Technology

[0003] Natural enemy insects are key natural factors controlling pest populations in farmland ecosystems. Ladybugs, lacewings, hoverflies, spiders, and parasitic wasps play a significant role in controlling major pests such as aphids and lepidopteran larvae. However, in intensive farmland, natural enemy insect populations often collapse during non-crop periods (such as after crop harvest) due to a lack of alternative food sources (nectar, pollen) and suitable habitats, failing to establish effective populations in the early stages of pest outbreaks.

[0004] Utilizing functional plants (nectar plants) to provide ecological support for natural enemies has become a research hotspot in pest ecological regulation. Chinese patent application CN202411837122.6 (publication date: December 13, 2024, invention title: A method for conserving natural enemies in wheat fields based on intercropping of *Cnidium monnieri* and broad beans) discloses a method for conserving natural enemies by intercropping *Cnidium monnieri* and broad beans on wheat field ridges, achieving good results. However, this method uses annual or biennial plants, requiring annual sowing, increasing the input of manpower and resources; and it is only applicable to single-season wheat production, not addressing cross-seasonal natural enemy conservation in rice-wheat rotation systems. Furthermore, existing technologies mostly focus on natural enemy conservation during a single crop season (such as the wheat season), lacking a systematic solution for how to effectively continue and transfer natural enemy populations between rice and wheat seasons.

[0005] Angelica sinensis ( Angelica sinensis As a traditional Chinese medicinal herb, *Osmanthus fragrans* produces abundant nectar and pollen during its flowering period, releasing unique volatile substances that strongly attract predatory insects. However, its systematic introduction into agricultural ecosystems, especially in conjunction with *Osmanthus fragrans* (*Osmanthus*), presents challenges. Osmanthus fragrans The combination of osmanthus and natural enemies, which provides habitat for shade-loving angelica and constructs a perennial, sustainable natural enemy conservation zone to achieve ecological control of pests throughout the entire rice-wheat rotation area, has not yet been reported. Summary of the Invention

[0006] To address the aforementioned problems, this invention discloses a rice-wheat rotation farmland ecosystem and a cross-seasonal pest control method based on an intercropping natural enemy conservation zone of Angelica sinensis and Osmanthus fragrans. The purpose of this invention is to overcome the shortcomings of existing pest control methods in rice-wheat rotation areas, such as over-reliance on chemical pesticides, difficulty in cross-seasonal continuation of natural enemy populations, and poor sustainability of ecological pest control measures. This method, by constructing a perennial natural enemy conservation zone, fully utilizes the ecological functions of functional plants, enabling the natural migration and settlement of natural enemy populations between rice and wheat seasons, forming a sustainable ecological pest control capacity, while also considering economic benefits, providing technical support for green agriculture.

[0007] The technical solution adopted in this invention is as follows: I. An application of osmanthus or angelica. Application of Osmanthus fragrans or Angelica sinensis in cross-seasonal pest control of cereal crops. The cereal crops are wheat and rice; cross-seasonal pest control involves intercropping Osmanthus fragrans and Angelica sinensis on the ridges of cereal fields to attract and retain natural enemies, which then migrate to the cereal fields to achieve pest control.

[0008] Specifically, cross-seasonal pest control involves intercropping osmanthus trees and angelica on the ridges of rice-wheat rotation fields to create a perennial natural enemy conservation zone. The volatile signaling substances released by the osmanthus trees and angelica attract, maintain, and propagate the natural enemy population. The conservationd natural enemy population then naturally migrates into adjacent farmland during the wheat and rice seasons, enabling continuous cross-seasonal pest control of the two crops.

[0009] II. A method for cross-seasonal pest control in rice-wheat rotation farmland based on the natural enemy conservation zone of Angelica sinensis-Osmanthus intercropping. The cross-seasonal pest control method of the present invention includes the following steps: S1. By intercropping osmanthus trees on the ridges of rice-wheat rotation fields ( Osmanthus fragrans ) and Angelica sinensis ( Angelica sinensis Construct a perennial natural enemy conservation zone and utilize the shading effect of Osmanthus trees to create a suitable habitat for shade-loving Angelica sinensis. The long side of the natural enemy conservation zone should ideally form an angle of 30-60° with the prevailing wind direction to facilitate the diffusion of volatile signaling substances and the migration of natural enemy insects. If the prevailing wind direction cannot be determined, it can be set perpendicular to the field ridges. The osmanthus trees and angelica in the natural enemy conservation zone should grow towards the farmland to facilitate the diffusion of biochemical signals released from the zone and the migration of natural enemy insects. For rice-wheat rotation fields, the field ridges need to be moderately hardened or reinforced with grass to withstand occasional compaction by agricultural machinery and prevent soil erosion.

[0010] S2, the perennial natural enemy conservation zone attracts, maintains and expands natural enemy populations by releasing biochemical signals; Among them, biochemical signals include volatile compounds, nectar and pollen resources produced by Angelica sinensis from the budding stage to the full bloom stage, and rich volatile terpenoids (such as linalool, ionone, etc.), nectar and pollen resources released by Osmanthus fragrans during the autumn full bloom stage. These signals and resources together constitute the chemical and nutritional basis for attracting and maintaining natural enemies. Natural enemy populations include predatory insects (such as ladybugs, lacewings, predatory bugs, etc.) and parasitic insects (such as various parasitic wasps, parasitic flies, etc.).

[0011] In practice, Angelica sinensis releases specific volatile substances (such as ligustilide and coumarin) from the budding stage to the full bloom stage, and provides abundant nectar and pollen resources. As a highly efficient biochemical signal, it attracts and maintains predatory natural enemy insects (such as ladybugs, lacewings, and hoverflies) and parasitic natural enemy insects (such as various parasitic wasps) over long distances. During the wheat harvest season, the natural enemy populations establish and proliferate within the conservation zone, and naturally migrate into paddy fields during the rice planting season, achieving continuous control over major pests such as aphids and lepidopteran larvae.

[0012] S3. The natural enemy populations that have been nurtured will be established and multiplied in sequence within the natural enemy conservation zone. Then, during the wheat and rice planting seasons, the nurtured natural enemy populations will naturally migrate into the farmland on both sides of the field ridges. The natural enemy populations that have migrated into the farmland will continuously control wheat and rice pests across seasons, thus achieving continuous pest control function throughout the entire rice-wheat rotation cycle.

[0013] Specifically, the natural enemy conservation zone is located on the field ridges, with a width of 1.0 to 2.0 meters. The ridges should be selected in sections with sufficient sunlight, good drainage, and easy access for agricultural machinery. The height of the ridges should be 20 to 30 centimeters higher than the field surface to avoid water accumulation in the field and affecting plant growth. Specifically, intercropping involves planting osmanthus trees in single rows along the field ridges, with a spacing of 3 to 5 meters between adjacent trees to ensure sufficient shade area after the canopy develops and to avoid affecting field operations. Angelica sinensis is planted in double rows or in holes between adjacent osmanthus trees or within the canopy projection area, with a row spacing of 20 to 30 centimeters and a hole spacing of 15 to 20 centimeters, making full use of the shade environment provided by the osmanthus trees.

[0014] To address the shade-loving nature of Angelica sinensis, during the hot and sunny summer period from wheat harvest to rice planting, black shade nets are erected above the Angelica sinensis planting area to provide supplementary shading protection, ensuring the healthy growth of the plants and the continued stable functioning of their ecological properties. The black shade nets can be removed before rice planting or after the Angelica sinensis canopy has closed. Based on field light intensity monitoring data, the hot and sunny summer period is specifically defined as a weather condition where the daily maximum temperature is ≥32℃ and the average midday (11:00-15:00) light intensity is ≥100,000 lux for more than three consecutive days. The shading rate of the black shade nets is preferably 40%±5%, which effectively reduces light intensity and temperature without affecting the photosynthesis of Angelica sinensis. The height of the black shade nets is 1.5–1.8 meters to mitigate the stress of strong light and high temperature.

[0015] The main pests controlled include one or more of the following: wheat aphid, cereal aphid, rice planthopper, rice stem borer, rice leaf roller, and armyworm. The herbivores attracted by the natural enemy conservation zone are different species of pests from wheat and rice pests. Wheat pests include the wheat aphid (Sitobion avenae), the grain aphid (Rhopalosiphumpadi), and the wheat two-forked aphid (Schizaphis graminum) from the Aphididae family; the armyworm (Mythimnaseparata) and the wheat stem moth (Ochsenheimeria taurella) from the Noctuidae family; the wheat thrips (Haplothrips tritici) from the Thripidae family; and the wheat stem fly (Meromyza saltatrix) from the Chloropidae family. Rice pests include the brown planthopper (Nilaparvata lugens), white-backed planthopper (Sogatella furcifera), and gray planthopper (Laodelphax striatellus) of the family Delphacidae; the rice stem borer (Chilo suppressalis), rice stem borer (Scirpophaga incertulas), and rice leaf roller (Cnaphalocrocis medinalis) of the family Pyralidae; the black-tailed leafhopper (Nephotettix cincticeps) of the family Cicadellidae; the rice thrips (Stenchaetothrips biformis) and rice tube thrips (Haplothrips aculeatus) of the family Thripidae; the rice water weevil (Lissorhoptrusoryzophilus) of the family Curculionidae; and the gall midge family (Cecidomyiidae). The rice gall midge (Orseolia oryzae); Predatory insect enemies include species of the family Syrphidae, the family Coccinellidae (Harmonia axyridis, Propylaea japonica, and Coccinella septempunctata), species of the family Staphylinidae, species of the family Chrysopidae, species of the family Dolichopodidae, and species of the order Araneae. Parasitic natural enemies include insects from the family Ichneumonidae, braconid wasps such as Macrocentrus linearis and Cotesia ruficrus, aphid wasps such as Aphidius avenae and Aphidius gifuensis, Trichogramma japonicum and Trichogramma ostriniae, brachymerialasus from the family Chalcididae, and Anagrus nilaparvatae from the family Mymaridae.

[0016] The budding to full bloom stage of Angelica sinensis (usually May to June) overlaps with the mid-to-late growth stages of wheat (such as the grain-filling stage) and the early growth stage of rice after transplanting (tillering stage). The full bloom stage of Osmanthus fragrans (usually September to October) overlaps with the late growth stage of rice (heading and grain-filling stage). This phenological design aims to achieve seamless temporal connection of natural enemy resources: Angelica sinensis provides the food and chemical signals needed for the migration and establishment of natural enemy populations in the early stage, while Osmanthus fragrans provides resources in the later stage to maintain its population vitality and size, thereby providing continuous support for natural enemies throughout the rice-wheat rotation cycle and strengthening the stability of ecological pest control functions.

[0017] Osmanthus trees are perennial woody plants; varieties with long flowering periods and strong adaptability, such as Osmanthus fragrans var. aurantiacus, Osmanthus fragrans var. sanguiana, or Osmanthus fragrans var. four-seasonis, are preferred. Angelica sinensis is a biennial or perennial herbaceous plant; varieties with high medicinal content and strong resistance, such as Min Gui No. 1 and Yun Gui No. 2, are preferred. The canopy of Osmanthus trees provides shade for the shade-loving Angelica sinensis, improving its growth conditions. The combination of the two forms a natural enemy conservation zone, which is a perennial system. Angelica sinensis is planted using a seedling transplanting method: from April to May each year, when the average temperature stabilizes at 10-12℃, select healthy Angelica sinensis seedlings that are 8-12 cm tall, have 4-6 true leaves, and are free from pests and diseases. Transplant the seedlings, with their original soil clumps (8-10 cm in diameter), to the field ridges. The planting holes should be 12-15 cm deep. Apply 100-150 grams of well-rotted organic fertilizer as base fertilizer to each seedling. Water thoroughly after planting to improve the survival rate.

[0018] While producing wheat or rice, reasonable field maintenance of the natural enemy conservation zone can be carried out without additional agricultural operations. The natural enemy conservation zone can operate continuously for more than 5 years without the need for annual replanting, significantly reducing maintenance costs. Field maintenance includes irrigation, weeding, etc.

[0019] In addition, during periods of high temperature and drought, drip irrigation or seepage irrigation should be used to provide precise watering for Angelica sinensis. The drip irrigation system mainly consists of a water source, water delivery pipes, and drip irrigation tape (or drip arrows) laid in the root zone of Angelica sinensis. The irrigation water temperature should be close to the surface temperature, and the amount of water used for each irrigation should be such that the soil moisture in the root zone is maintained at 60% to 70% of the field capacity, so as to avoid the plants from being hindered in growth due to excessive water shortage caused by high temperature transpiration.

[0020] The cross-seasonal pest control method of this invention achieves "building a reservoir in one season and sharing it in two seasons" by cultivating natural enemy populations. It achieves a control effect of 40% to 60% against pests such as wheat aphids, rice planthoppers, and rice stem borers, and reduces the application of chemical pesticides by 1 to 2 times.

[0021] Meanwhile, in late October to early November, after the autumn rice harvest and before the wheat planting, the medicinal part of Angelica sinensis root, which has grown for 2 to 3 years, can be harvested; during the peak flowering period from September to October, fresh Osmanthus flowers can be harvested in batches for food processing or to extract spices. While obtaining economic benefits, it is important to retain at least 1 / 3 of the flowers to ensure that they continue to attract natural enemies.

[0022] III. A farmland ecosystem for cross-seasonal pest control methods The farmland ecosystem includes rice-wheat rotation farmland, natural enemy conservation zones, black shade nets, and drip irrigation systems. The natural enemy conservation zones are set on the ridges of the rice-wheat rotation farmland. The natural enemy conservation zones are angelica-osmanthus intercropping natural enemy conservation zones. The black shade nets are placed above the angelica planting area. The drip irrigation system is arranged along the ridges of the rice-wheat rotation farmland and is set on one side of the angelica to provide precise water supply to the angelica during periods of high temperature and drought.

[0023] The black shade net is installed on a shade net support structure that can be quickly installed and disassembled. The support structure consists of height-adjustable metal or composite material columns and beams. The columns are fixed to the field ridges by the bottom base, and the beams are set on the top of the columns. The black shade net is laid on top of the beams, so that the angelica planting area below is in a controlled shaded environment. The drip irrigation system includes a water source, a water pump, a filter, a fertilizer applicator, main and branch water supply pipelines, and drip irrigation tape. The water source is connected to the main water supply pipeline through the water pump, and the filter and fertilizer applicator are connected in series on the main water supply pipeline. The main water supply pipeline is laid along the field ridges and connected to the drip irrigation tape through branch pipes. The drip irrigation tape is laid near the root zone of the Angelica sinensis plants.

[0024] This invention is the first to apply the traditional Chinese medicine Angelica sinensis to the ecological regulation of natural enemy insects. Its key advantage is that, during the rice-wheat rotation cycle, the natural enemy population cultivated and nurtured through functional plant belts during the wheat season can naturally migrate into surrounding paddy fields during the rice planting season to continue to play a role in pest control. This enables the natural enemy population to continuously expand and provide ecological services throughout the year, significantly improving the ability to control major pests such as aphids and lepidopteran larvae across seasons.

[0025] This invention relates to a farmland ecosystem that utilizes the recruitment and conservation of predatory and parasitic natural enemies to control pests across crops and seasons within a rice-wheat rotation system. The invention employs a combination of perennial plants, avoiding annual replanting and significantly reducing labor and seedling costs. The management of the natural enemy conservation zone is synchronized with field production, requiring no additional agricultural operations. This system not only effectively reduces the use of chemical pesticides in both rice and wheat seasons, improving the quality and safety of agricultural products, but also generates economic benefits through the continuous harvesting of medicinal herbs such as angelica and osmanthus for several years, providing an efficient and feasible technical approach for green and sustainable agriculture in rice-wheat rotation areas.

[0026] The beneficial effects of this invention are: The system is highly sustainable: the perennial combination of osmanthus and angelica avoids the labor and cost of replanting every year, the natural enemy conservation zone is stable in the long term, and the ecosystem service function is long-lasting.

[0027] Significant cross-seasonal pest control effect: For the first time, the natural migration and settlement of natural enemy populations between rice and wheat seasons has been achieved, solving the problem of natural enemy depletion during non-crop periods and improving the foresight and continuity of pest control.

[0028] Synergistic effect between ecological and economic benefits: While providing ecological pest control services, direct economic benefits can be obtained through the harvesting of angelica and osmanthus, thereby enhancing farmers' acceptance of the technology.

[0029] Highly adaptable and easy to manage: It alleviates adverse stress through adaptive measures such as shading nets and drip irrigation. The main agricultural operations are synchronized with field crops, without adding extra management burden, making it suitable for farms of different sizes. Attached Figure Description

[0030] Figure 1 A schematic diagram of the overall layout of the rice-wheat rotation farmland ecosystem.

[0031] Figure 2 This is a schematic diagram of the cross-sectional structure of the natural enemy conservation zone.

[0032] Figure 3 This is a schematic diagram of the shade net support structure.

[0033] Figure 4 This is a schematic diagram of the drip irrigation system layout. Detailed Implementation

[0034] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be described in further detail below.

[0035] like Figures 1-4 As shown, the farmland ecosystem of the present invention includes rice-wheat rotation farmland, natural enemy conservation belt, black shade net, and drip irrigation system; the natural enemy conservation belt is set on the field ridge of the rice-wheat rotation farmland, and the natural enemy conservation belt is an intercropping natural enemy conservation belt of Angelica sinensis and Osmanthus fragrans; the black shade net is arranged above the Angelica sinensis planting area; the drip irrigation system is arranged along the field ridge of the rice-wheat rotation farmland and is set on one side of the Angelica sinensis, for providing precise water supply to the Angelica sinensis during periods of high temperature and drought.

[0036] like Figure 3 As shown, the black shade net is arranged on a shade net support structure that can be quickly installed and disassembled; the support structure consists of height-adjustable metal or composite material columns and beams; the columns are fixed to the field ridges by the bottom base, and the beams are set on the top of the columns, on which the black shade net is laid, so that the angelica planting area below is in a controlled shaded environment. like Figure 4 As shown, the drip irrigation system includes a water source, a water pump, a filter, a fertilizer applicator, main and branch water supply pipes, and drip irrigation tape. The water source is connected to the main water supply pipe through the water pump, and the filter and fertilizer applicator are connected in series on the main water supply pipe. The main water supply pipe is laid along the field ridge and connected to the drip irrigation tape through branch pipes. The drip irrigation tape is laid near the root zone of the Angelica sinensis plant.

[0037] Example 1: Study on the dynamics of natural enemy communities at different growth stages of wheat Step 1: Setting up the field experimental area: The field experiment was conducted in Qianshanxia Village, Wuxing District, Huzhou City, Zhejiang Province, selecting a leveled wheat field with an area of ​​3 mu (approximately 2000 square meters). Before wheat sowing in November 2024, the field ridges were ecologically modified: The total area of ​​the experimental area was 3 mu, with a treatment area of ​​1.5 mu, implementing an intercropping pattern of Angelica sinensis and Osmanthus fragrans; the control area was 1.5 mu, located at the other end of the same plot, with a 50-meter buffer zone in the middle.

[0038] Osmanthus trees were planted at 4m spacing on the shady side of the field ridges, with approximately 25 trees planted in total. Angelica sinensis trees were planted in strips at a density of 0.3m x 0.4m on the sunny side of the field ridges, with approximately 250 clumps planted in total. The width ratio of the wheat field to the functional plant strip remained at 30m:1.5m.

[0039] Step 2: Conduct the experiment: Yellow sticky trap: Use an adhesive area of ​​18×17.5cm (effective area 320.4cm²). 2 Yellow sticky insect board.

[0040] In both the treatment and control areas, sampling lines were set up along the field ridges at gradients of 0m (on the ridge), 5m, and 10m. To accommodate smaller areas, three duplicate yellow sticky traps were placed along each sampling line, resulting in a total of nine sampling points / areas. The yellow sticky traps were suspended at a height of 80cm from the ground and 5cm away from the plant canopy.

[0041] Sampling time: First sampling: May 10, 2025 (start of wheat milk stage), yellow sticky traps will be collected and replaced; Second sampling: May 24, 2025 (wheat yellow stage), final collection will be carried out; Yellow sticky traps will be placed for 7 days after each sampling.

[0042] The samples were processed as follows: the recovered yellow sticky traps were brought back to the laboratory for arthropod isolation, counting, and identification under a stereomicroscope. Identification was performed at least to the family level, and major natural enemies (such as ladybugs, hoverflies, and parasitic wasps) were identified to the species level.

[0043] All arthropods are classified according to their functional groups as: parasites, predators, herbivores, and scavengers.

[0044] Comparative Example 1: Routine management control group Step 1: Set up a field control experimental area: The control area is located at the other end of the same plot, with an area of ​​1.5 acres, and a 50-meter buffer zone is set between it and the treatment area. Natural weeds are left along the field ridges of the control area, and no functional plants are planted.

[0045] Other management measures: wheat variety, sowing time, sowing density, fertilization, and irrigation were completely consistent with the treatment area; no chemical pesticides were applied to either the treatment area or the control area throughout the entire growth period, and comparisons were made only through differences in the natural enemy conservation zone.

[0046] Step 2: Conduct the experiment: Yellow sticky trap deployment: Sampling lines were set up along the field ridges of the control area at gradients of 0m (on the ridge), 5m, and 10m; three duplicate yellow sticky traps were placed along each sampling line, for a total of nine sampling points; the specifications, hanging height, and placement time of the yellow sticky traps were exactly the same as those in the treatment area; the same 18×17.5cm adhesive strips (effective area 320.4cm²) were used. 2 Yellow sticky insect traps; hang them at a height of 80cm from the ground and keep a distance of 5cm from the plant canopy.

[0047] Sampling time: First sampling: May 10, 2025 (start of wheat milk stage), yellow sticky traps will be collected and replaced; Second sampling: May 24, 2025 (wheat yellow stage), final collection will be carried out; Yellow sticky traps will be placed for 7 days after each sampling.

[0048] Sample processing method: The recovered yellow sticky traps were brought back to the laboratory for arthropod isolation, counting, and identification under a stereomicroscope; identification was performed at least to the family level, and major natural enemies (such as ladybugs, hoverflies, and parasitic wasps) were identified to the species level; all arthropods were classified according to their functional groups into: parasites, predators, herbivores, and detritivores. Record the data and compare it with Example 1. Analyze the results: Population dynamics of natural enemies: Table 1. Average number of natural enemies attracted (heads / plate, May 2025) at different treatment zones and distances Conclusion: Even in a small field of 3 mu (approximately 0.2 hectares), the number of natural enemies attracted in each location of the treatment area was higher than that in the control area. The trend of decreasing natural enemy numbers with increasing distance from functional vegetation zones remained evident.

[0049] Composition of major natural enemy groups: Treatment area (0m): The dominant natural enemy groups were Ladybugs (33.5% of predatory natural enemies), Hoverflies (26.8%), Lacewings (11.5%), and parasitic wasps from the Blue Wasps and the Scaled Wasps. The community structure was rich; Control area: The natural enemy community structure was simple, the number was small, and it was dominated by some broad-spectrum predators.

[0050] Table 2. Aphid population per 100 wheat plants and control efficacy in different treatment areas (survey conducted on May 24, 2025) Prevention efficacy calculation: Prevention efficacy (%) = (293.7-156.3) / 293.7×100% = 46.8% Conclusion: The number of wheat aphids per 100 plants in the treatment area was significantly lower than that in the control area (P<0.05), and the control effect reached 46.8%.

[0051] Pest control effectiveness assessment: A field survey was conducted during the yellow ripening stage (May 24).

[0052] In summary, this embodiment demonstrates that the intercropping pattern of Angelica sinensis and Osmanthus fragrans along field ridges in a relatively small plot of land (3 mu) still yields significant results: it effectively conserves natural enemies and maintains a stable control effect of over 46% against wheat aphids, proving the feasibility and effectiveness of this pattern in small-scale plots.

[0053] Suitable for demonstration and promotion: This scale has low investment costs and is easy to manage, making it very suitable as a demonstration field or promotion and application unit for farmers or family farms.

[0054] Economic benefit analysis: Investment: Osmanthus seedlings (25 seedlings × 30 yuan = 750 yuan), Angelica seedlings (250 clumps × 1 yuan = 250 yuan), one-time investment of about 1,000 yuan, can be used continuously for more than 5 years.

[0055] Yield: Angelica sinensis can be harvested in the second year after planting. Each clump produces about 180 grams of dried medicinal material, and 250 clumps will yield about 45 kilograms of dried Angelica sinensis. At a market price of 10 yuan / kg, the value is about 450 yuan / year. Osmanthus flowers can be harvested in moderation during the peak blooming period. The estimated annual yield of fresh flowers is 5-8 kilograms, with a value of about 200-300 yuan.

[0056] Savings: Reduces the application of chemical pesticides by 1-2 times, saving approximately 60-80 yuan per year in pesticide and application costs.

[0057] Overall net income: an average annual increase of approximately 550-670 yuan (450+250-80=620 yuan), accumulating to approximately 3100 yuan over 5 years, with an investment payback period of approximately 1.5-2 years.

[0058] This study provides direct data support and practical examples for promoting ecological functional plant measures on small and medium-sized plots.

[0059] Example 2: Verification of the effects of small-scale natural enemy conservation and cross-seasonal pest control in experimental fields Step 1: Set up the field test area This experiment was conducted in the experimental fields of the Agricultural Experiment Station in the West District of Zhejiang University's Zijingang Campus. The southern wheat field was selected as the observation area for the milk-ripe stage, and the northern wheat field as the observation area for the yellow-ripe stage. Both areas were in an open environment, and no chemical pesticides were applied throughout the entire growth period. The total area of ​​the southern experimental wheat field was approximately 1344 m². 2 The fields are planted in regular ridges, with each ridge measuring 3m wide and 24m long, and the furrows 0.3m wide. The surrounding environment is characterized by: fallow land to the north, a plastic greenhouse to the south, rapeseed fields to the east, and a greenbelt to the west, forming a semi-open ecological boundary. The wheat variety used is Jimai 22 (provided by the Crop Research Institute of the Shandong Academy of Agricultural Sciences), and the wheat is growing uniformly overall.

[0060] The experiment was set up with treatment and control areas: Treatment area: A natural enemy conservation zone was constructed on the east and south sides of the experimental wheat field (total length approximately 60m). Fifteen Osmanthus trees (variety 'Siji Gui') were planted at a spacing of 4m. Angelica sinensis ('Min Gui No. 1') was sown in double rows between the Osmanthus trees, with a row spacing of 25cm and a plant spacing of 20cm, retaining one plant per plant, for a total of approximately 150 clumps of Angelica sinensis. The field ridges were maintained at a width of 1.5m and 25cm above the field surface.

[0061] Step 2: Conduct the experiment Predator trapping and community survey: A systematic survey was conducted during the milk stage (May 12–18, 2025) and the yellow stage (May 25–31, 2025). Yellow sticky insect traps (18cm × 17.5cm) were placed at 0m (center axis of the field), 5m, and 10m (inwards towards the field) along the field ridges in both the treatment and control areas, with three replicates at each distance. The traps were hung at a uniform height of 80cm from the ground. Each trapping session lasted for 7 days. The collected samples were then subjected to arthropod classification and identification in the laboratory to distinguish between parasitic predators, predatory predators, herbivores, and neutral groups.

[0062] Response of natural enemies to tillage disturbance: To verify the shelter function of the natural enemy conservation zone under agricultural disturbance, five potted Angelica sinensis plants (with flowers) and five blank control pots were placed on the southwest ridge (treatment section) of the experimental field after wheat harvest and before mechanized tillage. During and for three hours after the tillage operation, arthropods migrating into the conservation zone and potted plants were collected by netting and visual inspection, with a focus on recording the species and number of natural enemies.

[0063] Pest population and damage survey: During the milk-ripe and yellow-ripe stages, the number of aphids (wheat long-tubed aphid and cereal constricted tubed aphid) and lepidopteran larvae on wheat plants was investigated using a five-point sampling method. 20 plants were investigated at each point, and the number of insects per 100 plants and the control efficacy were calculated.

[0064] Comparative Example 2: Step 1: Set up a field control test area: The control area is set up on the west and north ridges of the same test field (total length about 60m), forming a spatial control with the treatment area.

[0065] Basic setup of the control area: Field ridge specifications: 1.5m wide, 25cm above the field surface, consistent with the treatment area; Wheat variety: Jimai 22, sowing time and density were the same as the treatment area. Field ridge management: Maintain natural weed communities, mowing once per quarter, no functional plants planted; Other management: Fertilization and irrigation were synchronized with the treatment area, no chemical pesticides were used throughout the entire growth period.

[0066] Step 2: Conduct the experiment Enemy trapping and community survey: Yellow sticky trap placement: Yellow sticky traps (18cm×17.5cm) were placed at 0m, 5m and 10m intervals along the field ridges in the control area, with 3 replicates at each interval, and the hanging height was 80cm.

[0067] Sampling period: milk stage (May 12-18) and yellow stage (May 25-31), each lasting 7 days.

[0068] Sample processing: The recovered yellow sticky traps were isolated and identified as arthropods in the laboratory, and classified into parasitic natural enemies, predatory natural enemies, herbivores, and neutral groups.

[0069] Control group setup: Five blank control pots (25cm in diameter, without Angelica sinensis plants) were placed on the west side of the field ridge in the control area.

[0070] Observation periods: start of tillage (T0), T0+30min, T0+1h, T0+2h, T0+3h.

[0071] Collection methods: Net trapping and visual inspection were used to record the species and number of arthropods that migrated into the blank basins and control area field ridges.

[0072] Pest population and damage survey: Survey method: Five-point sampling method, with 20 wheat plants surveyed at each point; Survey period: milk stage (May 15) and yellow stage (May 28); Survey contents: the number of wheat aphids and cereal aphids, the number of lepidopteran larvae and the degree of damage; Control efficacy calculation: Control efficacy (%) = (Number of insects in the control area - Number of insects in the treatment area) / Number of insects in the control area × 100.

[0073] Statistical analysis: SPSS 26.0 was used to perform analysis of variance (ANOVA) and Duncan's test (P<0.05) to calculate the natural enemy community diversity index (H', D, J).

[0074] Analysis of the results: Composition of the natural enemy community: The field ridges (0m) in the treatment area were dominated by ladybugs (approximately 38%), hoverflies (22%), lacewings (14%), and parasitic wasps from the Braconidae and Trichogrammae families. The community structure was stable and highly diverse. In contrast, the control area was dominated by a small number of spiders and broad-spectrum predatory bugs, with significantly lower numbers and diversity of natural enemies.

[0075] Tillage disturbance response: During the tillage process, a total of 173 natural enemy individuals were captured in the Angelica sinensis conservation zone and potted plants in the treatment area. These individuals were mainly ladybugs, hoverflies, and lacewing larvae. Only 41 individuals were collected in the control area. This indicates that the Angelica sinensis-Osmanthus sinensis zone provides an effective refuge and recruitment center for natural enemies during farmland disturbance.

[0076] Table 3 Comparison of natural enemy attraction rates in different treatment areas (heads / plate, mean ± standard error) Table 4. Aphid population per 100 wheat plants and control efficacy in different treatment areas (survey conducted on May 24, 2025) Prevention efficacy calculation: Prevention efficacy (%) = (293.7-149.2) / 293.7×100% =49.2% Conclusion: The number of wheat aphids per 100 plants in the treatment area was significantly lower than that in the control area (P<0.05), and the control effect reached 49.2%.

[0077] In summary, this embodiment successfully verified the ecological function of the Angelica sinensis-Osmanthus fragrans natural enemy conservation zone in a medium-sized experimental field on a university campus. Even under complex surrounding conditions (adjacent to construction sites, warehouses, and greenhouses), the system significantly increased the number and diversity of natural enemy populations, maintained a stable control efficacy of approximately 47% against wheat aphids, and effectively mitigated the disturbance of agricultural operations to the natural enemy community. This study further corroborates the applicability and stability of the technology of this invention in small-to-medium-sized plots and under complex ecological boundary conditions, providing practical evidence for the promotion of ecological pest control technology in agricultural landscapes around urban areas.

Claims

1. An application of osmanthus or angelica, characterized in that: Application in cross-seasonal pest control of cereals.

2. The application of osmanthus tree or angelica according to claim 1, characterized in that: The grains mentioned are wheat and rice; the cross-seasonal pest control is achieved by intercropping osmanthus trees and angelica on the ridges of the grain fields to attract and retain natural enemies, which then migrate to the grain fields to control the pests.

3. A method for cross-seasonal pest control in rice-wheat rotation farmland based on the natural enemy conservation zone of Angelica sinensis-Osmanthus intercropping, characterized in that... Includes the following steps: S1. Constructing a natural enemy conservation zone: Constructing a natural enemy conservation zone by intercropping osmanthus trees and angelica on the ridges of rice-wheat rotation farmland; S2. Cultivating and maintaining natural enemy populations: The natural enemy conservation zone attracts, colonizes, and proliferates natural enemy populations by releasing biochemical signals; S3. Achieving cross-seasonal pest control: The natural enemy population cultivated in the natural enemy conservation zone then migrates into the farmland on both sides of the field ridges during the wheat and rice planting seasons. The natural enemy population that has migrated into the farmland controls wheat and rice pests across seasons.

4. A method for cross-season pest control in rice-wheat rotation farmland based on the natural enemy conservation zone of Angelica sinensis-Osmanthus intercropping, as described in claim 3, is characterized in that: In step S1, the angle between the long side of the natural enemy conservation zone and the prevailing wind direction of the rice-wheat rotation farmland ranges from 1 to 90°, and the growth direction of the osmanthus trees and angelica in the natural enemy conservation zone is towards the farmland; the field ridges of the rice-wheat rotation farmland are hardened or reinforced with grass. In step S2, the biochemical signals include volatile compounds, nectar and pollen resources produced by Angelica sinensis from the budding stage to the full bloom stage, and rich volatile terpenoids, nectar and pollen resources released by Osmanthus fragrans during the full bloom stage in autumn; the natural enemy population includes predatory natural enemy insects and parasitic natural enemy insects.

5. A method for cross-season pest control in rice-wheat rotation farmland based on the natural enemy conservation zone of Angelica sinensis-Osmanthus intercropping, as described in claim 3, is characterized in that: During the period of high temperature and strong sunlight in summer, from the time wheat is harvested to the time rice is planted, black shade nets are erected above the angelica planting area. The period of high temperature and strong sunlight in summer is defined as a period in which the daily maximum temperature exceeds 30°C and the light intensity is greater than 100,000 lux for more than three consecutive days. The shading rate of the black shade nets is 30%-50%, and the height of the black shade nets is 1.5-1.8 meters.

6. A method for cross-season pest control in rice-wheat rotation farmland based on the natural enemy conservation zone of Angelica sinensis-Osmanthus intercropping, as described in claim 3, is characterized in that: The main pests controlled include one or more of the following: wheat aphid, cereal aphid, rice planthopper, rice stem borer, rice leaf roller, and armyworm. The herbivores attracted by the natural enemy conservation zone are different species of pests from wheat and rice pests; the wheat pests include wheat long-tubed aphid, cereal constrictor aphid, and wheat two-forked aphid (Aphididae), armyworm (Noctuidae), wheat husk thrips (Thripsidae), wheat stem fly (Sterculiae) and wheat stem moth (Noctuidae). The rice pests mentioned include brown planthopper, white-backed planthopper, and gray planthopper of the planthopper family; rice stem borer, rice leaf roller, and rice leaf roller of the pyralid family; black-tailed leafhopper of the leafhopper family; rice thrips and rice tube thrips of the thrips family; rice water weevil of the weevil family; and rice gall midge of the gall midge family. The predatory insect enemies include species of the Hippophae family, ladybugs such as the Heteromorpha, the Tortoise-striped Ladybug, and the Seven-spotted Ladybug of the Coccinellidae family, species of the Paederidae family, species of the Lacewing family, species of the Araneae order, and species of the Tabanidae family. Parasitic natural enemies include ichneumon wasps and ichneumon wasps of the family Ichneumonidae, long-spurred braconid wasps and velvety braconid wasps of the family Braconididae, oat aphid braconid wasps and tobacco aphid braconid wasps of the family Aphididae, rice stem borer Trichogramma wasps and corn stem borer Trichogramma wasps of the family Trichogramma wasps, large-legged wasps of the family Microbeidae, and rice leaf beetle Trichogramma wasps of the family Trichogramma wasps.

7. A method for cross-season pest control in rice-wheat rotation farmland based on the natural enemy conservation zone of Angelica sinensis-Osmanthus intercropping, as described in claim 3, is characterized in that: The budding to full bloom stage of Angelica sinensis covers the middle and late growth stages of wheat and the early growth stage of rice after transplanting; the full bloom stage of Osmanthus fragrans covers the late growth stage of rice; Osmanthus fragrans is a perennial woody plant, and Angelica sinensis is a biennial or perennial herbaceous plant; Angelica sinensis is planted by seedling transplanting: in April to May each year, when the average temperature reaches 10-12℃, select healthy Angelica sinensis plants with a height of 8-12 cm, 4-6 true leaves, and no pests or diseases, and transplant the Angelica sinensis plants with their original soil clumps with a diameter of 8-10 cm to the field ridges; the planting depth is 12-15 cm, and 100-150 grams of decomposed organic fertilizer is applied as base fertilizer at the planting position of each Angelica sinensis plant, and water is applied after planting.

8. A method for cross-season pest control in rice-wheat rotation farmland based on the natural enemy conservation zone of Angelica sinensis-Osmanthus intercropping, as described in claim 3, is characterized in that: While producing wheat or rice, field maintenance is carried out on the natural enemy conservation zone; the field maintenance includes irrigation, weeding, etc.

9. A farmland ecosystem used in any one of the cross-seasonal pest control methods according to claims 1-8, characterized in that: The system includes rice-wheat rotation farmland, natural enemy conservation belts, black shade nets, and drip irrigation systems. The natural enemy conservation belts are set on the ridges of the rice-wheat rotation farmland. The natural enemy conservation belts are angelica-osmanthus intercropping natural enemy conservation belts. The black shade nets are placed above the angelica planting area. The drip irrigation system is arranged along the ridges of the rice-wheat rotation farmland and is set on one side of the angelica plantation to provide precise water supply to the angelica plantation during periods of high temperature and drought.

10. The farmland ecosystem according to claim 9, characterized in that: The black shade net is arranged on a shade net support structure that can be quickly installed and disassembled; the support structure consists of height-adjustable metal or composite material columns and beams; the columns are fixed to the field ridges by a bottom base, and the beams are mounted on the top of the columns, on which the black shade net is laid, so that the angelica planting area below is in a controlled shaded environment. The drip irrigation system includes a water source, a water pump, a filter, a fertilizer applicator, main and branch water supply pipelines, and drip irrigation tape. The water source is connected to the main water supply pipeline via the water pump, and the filter and fertilizer applicator are connected in series on the main water supply pipeline. The main water supply pipeline is laid along the field ridges and connected to the drip irrigation tape via branch pipes. The drip irrigation tape is laid near the root zone of the Angelica sinensis plants.

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