A method for directional growth of cassava tubers and intercropping with *Caulis Amaranthus rubra*

Abstract

This invention discloses a method for intercropping cassava tubers with *Caulis Amaranthus rubra*, belonging to the field of plant intercropping technology. The method includes: (1) cassava variety selection; (2) constructing a cement pillar planting frame, using wires pulled from adjacent cement pillars to provide a climbing net for *Caulis Amaranthus rubra*; (3) planting *Caulis Amaranthus rubra* on one side of the cement pillar; (4) planting cassava on the other side of the cement pillar; (5) fertilizing cassava in the tuber-oriented growth area; and focusing irrigation on the oriented growth area during drought; (6) field management; and (7) harvesting. This invention uses an intercropping model of cassava and *Caulis Amaranthus rubra* to increase the economic benefits of early-stage *Caulis Amaranthus rubra* planting, and utilizes cement pillars to achieve directional growth of cassava tubers. Cassava provides shade and protection for *Caulis Amaranthus rubra*, ensuring its normal growth in summer, improving growth efficiency, and accelerating economic benefits. This invention effectively achieves directional growth control of cassava, facilitates centralized harvesting, reduces harvesting damage, improves harvesting efficiency, and enhances the marketability of cassava.

Description

Technical Field

[0001] This invention belongs to the field of crop intercropping technology, specifically relating to a method for intercropping cassava tubers with *Caulis Amaranthus rubra*. Background Technology

[0002] Cassava is one of the world's three major tuber crops, widely cultivated in tropical and subtropical regions of my country, particularly in South and Southwest China, where it is an important starch and energy crop. Traditional cassava cultivation often employs monoculture, which leads to soil nutrient depletion, decreased fertility, and reduced yield per unit area, severely impacting economic efficiency. Furthermore, it fails to fully utilize vertical space, relying solely on horizontal land, resulting in low utilization rates of light, heat, and land resources. The underground tubers of cassava grow without directional guidance, typically radiating outwards into deeper soil layers, exhibiting randomness and a scattered distribution. This makes accurate tuber location during harvesting difficult, requiring extensive deep tilling, which is labor-intensive, inefficient, and prone to breaking tubers, affecting marketability and integrity. Even mechanical harvesting is inconvenient, often resulting in tuber crushing and high loss rates.

[0003] While existing technologies include cassava intercropping models, such as cassava intercropping with peanuts or cassava intercropping with corn, which improve land and light resource utilization to some extent, the problem of unreasonable crop combinations still exists. Either the crops compete with cassava for light and nutrients, or they fail to achieve ecological complementarity, thus negatively impacting the growth of the intercropped plants. Furthermore, no publicly available technology has been developed to regulate the directional growth of cassava tubers, making it difficult to solve the problems of low harvesting efficiency and easily broken tubers during digging.

[0004] Erythropalum scandens Blume, also known as maiden's vegetable, ox-ear vine, withered vine, hooked flower, side amaranth, and fine green vine, is a perennial woody vine unique to karst landforms. It is a vine with both medicinal and edible uses, possessing high economic value. Erythropalum scandens Blume is shade-tolerant, prefers cool environments, is highly adaptable, and tolerates extreme cold and drought. However, in the height of summer, young seedlings are highly susceptible to sunscald, affecting survival rate and growth rate. Furthermore, it requires pruning and shaping, and only reaches full production after three years of cultivation; its slow growth and slow returns are bottlenecks restricting its large-scale cultivation.

[0005] Therefore, how to intercrop cassava and red vine, regulate the directional growth of cassava, achieve spatial complementarity, superimposed benefits, improve harvesting efficiency, increase the early income of red vine planting, and shorten the planting return cycle will be of great significance to promoting the planting of cassava and red vine. Summary of the Invention

[0006] The purpose of this invention is to provide a method for directional intercropping of cassava tubers with *Cephalotaxus fortunei*. This intercropping method increases the economic benefits of early-stage *Cephalotaxus fortunei* planting. Cement pillars are used to guide the directional growth of cassava tubers, and the pillars are interlocked to guide the growth of *Cephalotaxus fortunei*. During its vigorous summer growth period, the cassava provides shade and protection for the *Cephalotaxus fortunei*, ensuring its normal summer growth, improving growth efficiency, and increasing economic benefits.

[0007] A method for directional intercropping of cassava tubers with *Cephalotaxus fortunei* includes the following steps: (1) Cassava variety selection: Select cassava varieties with upright plant type and lodging resistance; (2) Constructing shade structures and planting racks: Bury cement pillars on the planting ridges with a spacing of 120-150cm between pillars; then pull horizontal wires across adjacent cement pillars, with 2-3 layers of horizontal wires and a spacing of 20-25cm between horizontal wires. The bottom layer of horizontal wires is 30-40cm from the ground to form a planting rack. On the planting plot, construct a shade structure and cover it with a shade net with a shading rate of 50%-60%; complete this before transplanting / sowing the red ivy to ensure that the seedlings can obtain a suitable shaded environment after transplanting and avoid damage from strong light.

[0008] (3) Cassava planting: early spring, March; one week before planting, cover the planting ridge with black plastic film; when planting, dig cassava planting pits on the plastic film 8-10cm in front of the cement pillar; select healthy and disease-free cassava seed stems, cut them into 15-20cm long sections, each section retaining 2-3 buds, when planting, place the seed stems with the buds facing up and diagonally downward in the cassava planting pit, after planting, cover with 5-8cm of soil and lightly compact; plant one cassava plant for each cement pillar.

[0009] (4) Planting of Red Vine: Red vine is planted 2 weeks after cassava planting. The seedlings of Red Vine are planted in the planting hole, 15-20cm away from the cement pillar. The planting row spacing of Red Vine is 50-60m. When the seedlings grow to 30-40cm, the stems are manually guided to grow upward along the horizontal wire of the planting frame. They are lightly tied with a strap to avoid damaging the stems. When the main vine grows to 90-100cm, the top is pinched off to promote the growth of secondary vines. 10-13 secondary vines are retained. When the secondary vines grow to 30-40cm, tertiary vines are cultivated. During this period, overly dense lateral vines and diseased or weak vines are removed in time to maintain ventilation and light penetration inside the planting frame. (5) Fertilizer management: Before planting, apply base fertilizer to the planting plot, using 1500-2000 kg of well-rotted organic fertilizer and 30-40 kg of compound fertilizer (nitrogen, phosphorus, and potassium ratio 1:1:1) per mu; spread evenly and then plow deeply into the soil to avoid exposing the fertilizer; when the cassava seedlings are 30-40 cm tall, apply topdressing fertilizer by opening shallow trenches on the side where the cassava tubers are growing in the direction of growth, using 15-20 kg of compound fertilizer (nitrogen, phosphorus, and potassium ratio 2:1:2) per mu.  Apply 800-1000 kg of well-rotted organic fertilizer per mu (667 square meters); apply a second top dressing 100-120 days after cassava planting, using 18-20 kg of compound fertilizer (NPK ratio 2:1:2) and 18 kg of potassium fertilizer per mu.   ~20kg; Topdressing of cassava should be concentrated in the directional growth zone of the tubers, which is the opposite side of the cement pillar. After covering with soil, water should be applied. During drought, the directional growth zone should be irrigated in a focused manner to maintain soil moisture at 60%-70%. (6) Field management: After cassava has grown to a height of 60-80cm for 2 months, the shade net should be removed to allow ventilation and light to pass through, providing light for the climbing and healthy growth of the cassava vines; at the same time, weeds should be removed regularly to prevent weeds from competing with the cassava vines and cassava for nutrients; and attention should be paid to the prevention and control of diseases and pests; no additional trellises are needed during the growth period of cassava, as its self-supporting characteristics provide shade for the cassava vines. (7) Harvesting and picking: Cassava can be harvested in November of the year of planting and can be planted again the following year; Red vine enters the high-yield period in the third year of planting and is harvested according to the condition of the tender shoots of Red vine.

[0010] As a preferred technical solution, the cassava variety selected is Guire 4, Guishu 1505, or Guishu 1508.

[0011] As a preferred technical solution, the cassava varieties Guire 4, Guishu 1505 and Guishu 1508 are intercropped in rows in a ratio of 3:2:1.

[0012] As a preferred technical solution, the cement column has a height of 200-220cm, a burial depth of 40-50cm, and a height of 150-170cm above the ground.

[0013] As a preferred technical solution, in step (2) of building the planting frame, the longitudinal wire is pulled at the horizontal wire to form a grid with a specification of 20-25cm×20-25cm.

[0014] As a preferred technical solution, step (4) involves planting cassava, with one cassava plant corresponding to each cement pillar.

[0015] As a preferred technical solution, the cassava fertilization management process in step (5) also includes topping and dwarfing the cassava when it grows to 60-70cm, and spraying a dwarfing agent with a concentration of 0.03%; the dwarfing agents paclobutrazol and uniconazole are mixed in a ratio of 2:1.

[0016] The advantages of this invention compared to the prior art are: 1. This invention employs physical isolation with cement pillars combined with directional fertilization and irrigation technology to precisely guide cassava tubers to grow in a concentrated manner on the non-intercropping side (opposite to the cement pillar), completely solving the problems of dispersed growth and difficult harvesting associated with traditional cassava tubers. The concentrated growth of cassava tubers significantly reduces mechanical damage and labor costs during harvesting, improving harvesting efficiency and ensuring the integrity of the tuber appearance, thus significantly enhancing the marketability and competitiveness of cassava. Furthermore, for scientific research and breeding, the concentrated growth of tubers facilitates accurate yield statistics and trait analysis, providing standardized experimental conditions for breeding research. In addition, the concentrated growth model is compatible with mechanized harvesting operations, further reducing labor costs and increasing the feasibility of large-scale planting, thus balancing the dual value of production applications and scientific research needs.

[0017] 2. This invention employs a three-dimensional cultivation model of intercropping cassava and red vine, achieving efficient utilization of resources such as space and nutrients. Spatially, the upright growth habits of cassava and the climbing growth habits of red vine complement each other, fully utilizing vertical space in the field, breaking the spatial limitations of traditional monoculture, significantly improving light energy utilization, and resulting in a substantial increase in the accumulation of photosynthetic products per unit area. Nutrient-wise, targeted fertilization technology precisely supplies the nutrients needed for the growth of both crops, effectively avoiding nutrient competition between crops during intercropping, while reducing fertilizer loss and improving fertilizer utilization. This not only lowers fertilization costs but also promotes the simultaneous and robust growth of cassava and red vine, achieving the goal of efficient resource utilization of "two harvests from one plot of land."

[0018] 3. This invention achieves ecological synergy between cassava and *Cephalotaxus fortunei*, effectively enhancing the stability and resilience of the planting system. The broad leaves of cassava plants naturally provide shade for *Cephalotaxus fortunei* seedlings, effectively mitigating sunscald caused by high temperatures and strong sunlight in midsummer, reducing seedling mortality, and significantly improving the survival rate of transplanted *Cephalotaxus fortunei*. Simultaneously, the climbing growth of *Cephalotaxus fortunei* can cover the ground, reducing weed growth and competition for nutrients between weeds and crops, thus reducing weeding costs. Furthermore, the different root depths of the two crops allow for full utilization of water and nutrients in different soil layers, improving soil physicochemical properties, enhancing soil fertility, and forming a sustainable ecological planting system. This reduces agricultural inputs such as chemical fertilizers and herbicides, balancing ecological protection and planting benefits.

[0019] 4. This invention effectively solves the industry pain points of late-blooming and unprofitable early-stage *Caulis Amaranta*, achieving an organic combination of short-term and long-term benefits. *Caulis Amaranta* requires 3 years to reach full production after planting, while cassava can harvest tubers and generate economic benefits in the same year, effectively covering early planting and management costs, alleviating growers' financial pressure, and reducing planting risks. In terms of output value, cassava yields approximately 2-3 tons of tubers per mu (approximately 0.067 hectares), with a market value of 2600-3000 yuan per mu; after *Caulis Amaranta* reaches full production, its tender leaves yield approximately 1500-1800 kg per mu, with a value of around 8000 yuan per mu. The combined output value of intercropping these two crops is 3-5 times higher than monoculture of cassava, significantly increasing growers' economic income. Furthermore, as a specialty vegetable, *Caulis Amaranta* has strong market demand; intercropping can enrich planting categories, broaden growers' income channels, promote the upgrading of specialty agricultural industries, and has good prospects for industrialization and promotion. Attached Figure Description

[0020] Figure 1 This is a diagram showing the growth of *Caulis Amaranthus* intercropped with cassava two months after planting.

[0021] Figure 2 The growth status of cassava intercropped with red vine 7 months after transplanting.

[0022] Figure 3 The image shows the growth of cassava tubers after intercropping with *Caulis Amaranthus rubra* (red vine) for 250-270 days. Detailed Implementation

[0023] The following embodiments are intended to provide a more comprehensive understanding of the present invention by those skilled in the art. These embodiments are only a portion of, and not all, of the invention, and are not intended to limit the invention in any way. However, those skilled in the art should understand that various changes in form and detail can be made without departing from the scope defined by the claims.

[0024] Example 1 A method for directional intercropping of cassava tubers with *Cephalotaxus fortunei* includes the following steps: (1) Cassava variety selection: Select cassava varieties with upright plant type and lodging resistance; Cassava varieties such as Guire No. 4, Guishu 1505 and Guishu 1508 are intercropped in rows in a ratio of 3:2:1.

[0025] (2) Constructing the shade structure and planting rack: Bury cement pillars in the planting ridges. The cement pillars are 200cm high, buried 40-50cm deep, and 150-160cm above the ground. The spacing between the pillars is 120cm. Then, pull horizontal wires to the adjacent cement pillars. Pull three layers of horizontal wires with a spacing of 25cm. The bottom layer of horizontal wires is 30-40cm from the ground. Pull vertical wires at the horizontal wires to form a grid of 25cm×25cm to form the planting rack.

[0026] On the planting plot, construct a shade structure and cover it with a shade net with a shading rate of 50%-60%; complete this before transplanting / sowing the red ivy to ensure that the seedlings can obtain a suitable shaded environment after transplanting and avoid damage from strong light.

[0027] (3) Cassava planting: early spring, March; one week before planting, cover the planting ridge with black plastic film; when planting, dig cassava planting pits on the plastic film 8-10cm in front of the cement pillar; select healthy and disease-free cassava seed stems, cut them into 15-20cm long sections, each section retaining 2-3 buds, when planting, place the seed stems with the buds facing up and diagonally downward in the cassava planting pit, after planting, cover with 5-8cm of soil and lightly compact; plant one cassava plant for each cement pillar.

[0028] (4) Planting of Red Vine: Red vine is planted 2 weeks after cassava planting. The seedlings of Red Vine are planted in the planting hole, 15-20cm away from the cement pillar. The planting row spacing of Red Vine is 50-60m. When the seedlings grow to 30-40cm, the stems are manually guided to grow upward along the horizontal wire of the planting frame. They are lightly tied with straps to avoid damaging the stems. When the main vine grows to 90cm, the top is pinched off to promote the growth of secondary vines. 10-13 secondary vines are retained. When the secondary vines grow to 30-40cm, tertiary vines are cultivated. During this period, overly dense lateral vines and diseased or weak vines are removed in time to maintain ventilation and light penetration inside the planting frame. (5) Fertilizer management: Before planting, apply base fertilizer to the planting plot, using 2000 kg of well-rotted organic fertilizer and 30 kg of compound fertilizer (N, P, K ratio 1:1:1) per mu; spread evenly and then plow deeply into the soil to avoid fertilizer exposure; when the cassava seedlings are 30-40 cm tall, apply topdressing fertilizer by opening shallow trenches on the side of the cassava tuber's directional growth, using 15 kg of compound fertilizer (N, P, K ratio 2:1:2) per mu.   kg; apply a second top dressing 100-120 days after cassava planting, applying 18 kg of compound fertilizer (N, P, K ratio 2:1:2) and 20 kg of potassium fertilizer per mu of planting area. Cassava top dressing should be concentrated in the directional growth zone of the tubers, i.e., the opposite side of the cement pillar, and watered after covering with soil; in dry conditions, focus on irrigating the directional growth zone to maintain soil moisture of 60%-70%.

[0029] When the cassava grows to 60-70cm in height, it is topped to dwarf it and sprayed with a dwarfing agent at a concentration of 0.03%; the dwarfing agents paclobutrazol and uniconazole are mixed in a ratio of 2:1.

[0030] (6) Field management: After cassava has grown to a height of 60-80cm for 2 months, the shade net should be removed to allow ventilation and light to pass through, providing light for the climbing and healthy growth of the cassava vines; at the same time, weeds should be removed regularly to prevent weeds from competing with the cassava vines and cassava for nutrients; and attention should be paid to the prevention and control of diseases and pests; no additional trellises are needed during the growth period of cassava, as its self-supporting characteristics provide shade for the cassava vines. (7) Harvesting and picking: Cassava can be harvested in November of the year of planting and can be planted again the following year; Red vine enters the high-yield period in the third year of planting and is harvested according to the condition of the tender shoots of Red vine.

[0031] Example 2 A method for directional intercropping of cassava tubers with *Cephalotaxus fortunei* includes the following steps: (1) Cassava variety selection: Select cassava varieties with upright plant type and lodging resistance; select Gui Re No. 4 cassava variety.

[0032] (2) Constructing shade structures and planting racks: Bury cement pillars on the planting ridges. The height of the cement pillars is 220cm, the burial depth is 40-50cm, and the height above the ground is about 170cm. The spacing between the pillars is 150cm. Then, pull horizontal wires on the adjacent cement pillars. Pull three layers of horizontal wires with a spacing of 25cm. The bottom layer of horizontal wires is 30-40cm from the ground. Pull longitudinal wires at the horizontal wires to form a grid of 20cm×20cm to form a planting rack.

[0033] On the planting plot, construct a shade structure and cover it with a shade net with a shading rate of 50%-60%; complete this before transplanting / sowing the red ivy to ensure that the seedlings can obtain a suitable shaded environment after transplanting and avoid damage from strong light.

[0034] (3) Cassava planting: early spring, March; one week before planting, cover the planting ridge with black plastic film; when planting, dig cassava planting pits on the plastic film 8-10cm in front of the cement pillar; select healthy and disease-free cassava seed stems, cut them into 15-20cm long sections, each section retaining 2-3 buds, when planting, place the seed stems with the buds facing up and diagonally downward in the cassava planting pit, after planting, cover with 5-8cm of soil and lightly compact; plant one cassava plant for each cement pillar.

[0035] (4) Planting of Red Vine: Red vine is planted 2 weeks after cassava planting. The seedlings of Red Vine are planted in the planting hole, 15-20cm away from the cement pillar. The planting row spacing of Red Vine is 50-60m. When the seedlings grow to 30-40cm, the stems are manually guided to grow upward along the horizontal wire of the planting frame. They are lightly tied with straps to avoid damaging the stems. When the main vine grows to 100cm, the top is pinched off to promote the growth of secondary vines. 10-13 secondary vines are retained. When the secondary vines grow to 30-40cm, tertiary vines are cultivated. During this period, overly dense lateral vines and diseased or weak vines are removed in time to maintain ventilation and light penetration inside the planting frame. (5) Fertilizer management: Before planting, apply base fertilizer to the planting plot, using 1500 kg of well-rotted organic fertilizer and 40 kg of compound fertilizer (N, P, K ratio 1:1:1) per mu; spread evenly and then plow deeply into the soil to avoid exposing the fertilizer; when the cassava seedlings are 30-40 cm tall, apply topdressing fertilizer by opening shallow trenches on the side where the cassava tubers are growing in the direction of growth, using 20 kg of compound fertilizer (N, P, K ratio 2:1:2) per mu.   kg; apply a second top dressing 100-120 days after cassava planting, applying 18 kg of compound fertilizer (N, P, K ratio 2:1:2) and 18 kg of potassium fertilizer per mu of planting area. Cassava top dressing should be concentrated in the directional growth zone of the tubers, i.e., the opposite side of the cement pillar, and watered after covering with soil; in dry conditions, focus on irrigating the directional growth zone to maintain soil moisture of 60%-70%.

[0036] When the cassava grows to 60-70cm in height, it is topped to dwarf it and sprayed with a dwarfing agent at a concentration of 0.03%; the dwarfing agents paclobutrazol and uniconazole are mixed in a ratio of 2:1.

[0037] (6) Field management: After cassava has grown to a height of 60-80cm for 2 months, the shade net should be removed to allow ventilation and light to pass through, providing light for the climbing and healthy growth of the cassava vines; at the same time, weeds should be removed regularly to prevent weeds from competing with the cassava vines and cassava for nutrients; and attention should be paid to the prevention and control of diseases and pests; no additional trellises are needed during the growth period of cassava, as its self-supporting characteristics provide shade for the cassava vines. (7) Harvesting and picking: Cassava can be harvested in November of the year of planting and can be planted again the following year; Red vine enters the high-yield period in the third year of planting and is harvested according to the condition of the tender shoots of Red vine.

[0038] Example 3 A method for directional intercropping of cassava tubers with *Cephalotaxus fortunei* includes the following steps: (1) Cassava variety selection: Select cassava varieties with upright plant type and lodging resistance; select Guishu 1505 as the cassava variety.

[0039] (2) Constructing shade structures and planting racks: Bury cement pillars on the planting ridges. The height of the cement pillars is 200cm, the burial depth is 40-50cm, and the height above the ground is about 150cm. The spacing between the pillars is 120cm. Then, pull horizontal iron wires on the adjacent cement pillars. Pull two layers of horizontal iron wires with a spacing of 20cm. The bottom layer of horizontal iron wires is 30-40cm from the ground to form a planting rack.

[0040] On the planting plot, construct a shade structure and cover it with a shade net with a shading rate of 50%-60%; complete this before transplanting / sowing the red ivy to ensure that the seedlings can obtain a suitable shaded environment after transplanting and avoid damage from strong light.

[0041] (3) Cassava planting: early spring, March; one week before planting, cover the planting ridge with black plastic film; when planting, dig cassava planting pits on the plastic film 8-10cm in front of the cement pillar; select healthy and disease-free cassava seed stems, cut them into 15-20cm long sections, each section retaining 2-3 buds, when planting, place the seed stems with the buds facing up and diagonally downward in the cassava planting pit, after planting, cover with 5-8cm of soil and lightly compact; plant one cassava plant for each cement pillar.

[0042] (4) Planting of Red Vine: Red vine is planted 2 weeks after cassava planting. The seedlings of Red Vine are planted in the planting hole, 15-20cm away from the cement pillar. The planting row spacing of Red Vine is 50-60m. When the seedlings grow to 30-40cm, the stems are manually guided to grow upward along the horizontal wire of the planting frame. They are lightly tied with a strap to avoid damaging the stems. When the main vine grows to 95cm, the top is pinched off to promote the growth of secondary vines. 10-13 secondary vines are retained. When the secondary vines grow to 30-40cm, tertiary vines are cultivated. During this period, overly dense lateral vines and diseased or weak vines are removed in time to maintain ventilation and light penetration inside the planting frame. (5) Fertilizer management: Before planting, apply base fertilizer to the planting area, with 1800 kg of decomposed organic fertilizer and 35 kg of compound fertilizer (N, P, K ratio 1:1:1) per mu; spread evenly and then plow deeply into the soil to avoid fertilizer exposure; when the cassava seedlings are 30-40 cm tall, apply topdressing fertilizer by opening shallow trenches on the directional growth side of the cassava tubers, with 1000 kg of decomposed organic fertilizer per mu; 100-120 days after planting, apply a second topdressing fertilizer, with 20 kg of compound fertilizer (N, P, K ratio 2:1:2) and 20 kg of potassium fertilizer per mu. Cassava topdressing should be concentrated in the directional growth area of ​​the tubers, which is the opposite side of the cement pillar, and watered after covering with soil; during drought, focus on irrigating the directional growth area to maintain soil moisture of 60%-70%.

[0043] When the cassava grows to 60-70cm in height, it is topped to dwarf it and sprayed with a dwarfing agent at a concentration of 0.03%; the dwarfing agents paclobutrazol and uniconazole are mixed in a ratio of 2:1.

[0044] (6) Field management: After cassava has grown to a height of 60-80cm for 2 months, the shade net should be removed to allow ventilation and light to pass through, providing light for the climbing and healthy growth of the cassava vines; at the same time, weeds should be removed regularly to prevent weeds from competing with the cassava vines and cassava for nutrients; and attention should be paid to the prevention and control of diseases and pests; no additional trellises are needed during the growth period of cassava, as its self-supporting characteristics provide shade for the cassava vines. (7) Harvesting and picking: Cassava can be harvested in November of the year of planting and can be planted again the following year; Red vine enters the high-yield period in the third year of planting and is harvested according to the condition of the tender shoots of Red vine.

[0045] Comparative Example 1 The conventional monoculture method for cassava cultivation is as follows: (1) Cassava variety selection: Select cassava varieties with upright plant type and lodging resistance. Plant Guire No. 4, Guishu 1505 and Guishu 1508 in rows with a ratio of 3:2:1.

[0046] (2) Cassava planting: Cassava should be planted starting in March in spring. Select healthy and disease-free cassava stems and cut them into 15-20cm long sections, with 2-3 buds on each section. When planting, place the stems with the buds facing up in the planting pit at a slight angle to the bottom of the slope. After planting, cover with 5-8cm of soil and lightly compact. (3) Cassava fertilization management: Before planting, apply base fertilizer to the planting plot, using 1500-2000 kg of well-rotted organic fertilizer and 30-40 kg of compound fertilizer (N, P, K ratio 1:1:1) per mu; spread evenly and then plow deeply into the soil to avoid exposing the fertilizer; when the cassava seedlings are 30-40 cm tall, apply topdressing fertilizer by opening shallow trenches on both sides of the cassava planting row, using 15-20 kg of compound fertilizer (N, P, K ratio 2:1:2) per mu.   kg; apply a second top dressing 100-120 days after cassava planting, using 18-20 kg of compound fertilizer (N, P, K ratio 2:1:2) and 18 kg of potassium fertilizer per mu of planting area.   ~20kg. Irrigate during dry periods to maintain soil moisture at 60%-70%.

[0047] (3) Field management: regularly remove weeds in the field to prevent weeds from competing with cassava for nutrients; at the same time, pay attention to the prevention and control of diseases and pests, and adopt existing conventional methods.

[0048] (4) Harvesting and picking: Cassava can be harvested in November of the year it is planted.

[0049] Comparative Example 2 The conventional cultivation method for *Ilex chinensis* involves first constructing a shade structure on the planting plot, covering it with a shade net providing 50-60% shading. Then, the bagged *Ilex chinensis* seedlings are transplanted onto planting ridges with a row spacing of (45-50) cm × (45-50) cm. Supports are erected and fixed on the ridges to facilitate seedling climbing. Before transplanting, well-rotted organic fertilizer and potassium chloride are applied to the planting pits, and the seedlings are thoroughly watered after transplanting. When the main vine reaches 90-100 cm, the top is pinched off to promote the growth of secondary vines. 10-13 secondary vines are retained. When the secondary vines reach 30-40 cm, tertiary vines are cultivated. During the canopy formation period, overly dense lateral vines and weak or diseased vines are promptly removed to maintain ventilation and light penetration within the planting frame. During the planting period, water and fertilizer management and pest and disease control are handled using existing conventional methods. In the third year after planting, when the plant enters its peak production period, the tender shoots can be harvested.

[0050] The cassava plant height, cassava tuber condition, and economic benefits of the methods in Example 1, Comparative Example 1, and Comparative Example 2 are recorded in Table 1 below.

[0051] Table 1. Comparison of growth and economic benefits of different planting methods

[0052] As shown in Table 1: (1) The method of this invention can effectively control the growth direction of cassava, achieving directional growth, thereby improving the economic benefits of cassava yield per mu. The economic benefits of cassava in the first year of planting can reach 2600-3000 yuan / mu, which is 4000 yuan / mu higher than the economic benefits of 2200-2500 yuan / mu for monoculture of cassava in Comparative Example 1. This is mainly because directionally grown cassava is easier to harvest, mechanical damage and labor costs are effectively controlled, the integrity of the tuber appearance is guaranteed, and the marketability of cassava is improved, thus improving economic benefits.

[0053] (2) The present invention uses a dwarfing agent to treat cassava, which can effectively reduce the height of cassava plants to 1.6-2.0m. It can regulate the main supply of nutrients to tuber growth, and at the same time reduce the probability of cassava stems breaking in strong winds, thereby increasing cassava yield and thus improving the economic benefits per mu.

[0054] (3) This invention uses cassava and red vine intercropping, which can realize the economic benefits per unit area more quickly than red vine monocropping, and can produce a harvest in the first year of intercropping. By the third year of planting, the dual economic benefits of cassava and red vine can be realized. The economic benefits of cassava monocropping are only generated by cassava, and the income per unit area is low. However, intercropping with high-value red vine can achieve an income of 10,600-11,000 yuan per unit area in the third year of planting, which is 2,600-3,000 yuan / mu higher than that of red vine monocropping.

Claims

1. A method for directional intercropping of cassava tubers with *Caulis Amaranthus rubra*, characterized in that: Includes the following steps: (1) Cassava variety selection: Select cassava varieties with upright plant type and lodging resistance; (2) Constructing shade structures and planting racks: Bury cement pillars in the planting ridges with a spacing of 120-150cm between pillars; then stretch horizontal iron wires to the adjacent cement pillars, with 2-3 layers of horizontal iron wires and a spacing of 20-25cm between the horizontal iron wires. The bottom layer of horizontal iron wires should be 30-40cm from the ground to form a planting rack; build shade structures on the planting plots and cover them with shade nets with a shading rate of 50%-60%. (3) Cassava planting: early spring, March; one week before planting, cover the planting ridge with black plastic film; when planting, dig cassava planting pits on the plastic film 8-10cm in front of the cement pillar; select healthy and disease-free cassava seed stems, cut them into 15-20cm long sections, each section retaining 2-3 buds, when planting, place the seed stems with the buds facing up and diagonally downward in the cassava planting pit, after planting, cover with 5-8cm of soil and lightly compact; (4) Planting of Red Vine: Red vine is planted 2 weeks after cassava planting. The seedlings of Red Vine are planted in the planting hole, 15-20cm away from the cement pillar. The planting row spacing of Red Vine is 50-60m. When the seedlings grow to 30-40cm, the stems are manually guided to grow upward along the horizontal wire of the planting frame. They are lightly tied with a strap to avoid damaging the stems. When the main vine grows to 90-100cm, the top is pinched off to promote the growth of secondary vines. 10-13 secondary vines are retained. When the secondary vines grow to 30-40cm, tertiary vines are cultivated. During this period, overly dense lateral vines and diseased or weak vines are removed in time to maintain ventilation and light penetration inside the planting frame. (5) Fertilizer management: Before planting, apply base fertilizer to the planting area, using 1500-2000 kg of well-rotted organic fertilizer and 30-40 kg of compound fertilizer per mu; spread evenly and then plow deeply into the soil to avoid exposing the fertilizer; when the cassava seedlings are 30-40 cm tall, apply topdressing fertilizer by opening shallow trenches on the side where the cassava tubers are growing in the direction of growth, using 15-20 kg of compound fertilizer per mu.   Apply 800-1000 kg of well-rotted organic fertilizer per mu (667 square meters); apply a second top dressing 100-120 days after cassava planting, using 18-20 kg of compound fertilizer and 18 kg of potassium fertilizer per mu.   ~20kg; Topdressing of cassava should be concentrated in the directional growth zone of the tubers, which is the opposite side of the cement pillar. After covering with soil, water should be applied. During drought, the directional growth zone should be irrigated in a focused manner to maintain soil moisture at 60%-70%. (6) Field management: After cassava has grown to a height of 60-80cm for 2 months, the shade net should be removed to allow ventilation and light to pass through, providing light for the climbing and healthy growth of the cassava vines; at the same time, weeds should be removed regularly to prevent weeds from competing with the cassava vines and cassava for nutrients; and attention should be paid to the prevention and control of diseases and pests; no additional trellises are needed during the growth period of cassava, as its self-supporting characteristics provide shade for the cassava vines. (7) Harvesting and picking: Cassava can be harvested in November of the year of planting and can be planted again the following year; Red vine enters the high-yield period in the third year of planting and is harvested according to the condition of the tender shoots of Red vine.

2. The method for directional intercropping of cassava tubers with *Caulis Amaranthus* according to claim 1, characterized in that: The selected cassava varieties are Guire 4, Guishu 1505, or Guishu 1508.

3. The method for directional intercropping of cassava tubers with *Caulis Amaranthus* according to claim 2, characterized in that: The cassava varieties used were Guire 4, Guishu 1505 and Guishu 1508, which were intercropped in a ratio of 3:2:

1.

4. The method for directional intercropping of cassava tubers with *Caulis Amaranthus* according to claim 1, characterized in that: The cement column is 200-220cm high, buried 40-50cm deep, and protrudes 150-170cm above the ground.

5. The method for directional intercropping of cassava tubers with *Caulis Amaranthus* according to claim 1, characterized in that: In step (2) of building the planting frame, the longitudinal wires are pulled at the horizontal wires to form a grid with a specification of 20-25cm×20-25cm.

6. The method for directional intercropping of cassava tubers with *Caulis Amaranthus* according to claim 1, characterized in that: In step (4), cassava is planted, with one cassava planted for each cement pillar.

7. The method for directional intercropping of cassava tubers with *Caulis Amaranthus* according to claim 1, characterized in that: In step (5) of cassava fertilization management, the cassava is topped and dwarfed when it grows to 60-70cm, and a dwarfing agent with a concentration of 0.03% is sprayed; the dwarfing agents paclobutrazol and uniconazole are mixed in a ratio of 2:1.

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