A cultivation method for increasing yield of watermelon interplanted with sunflower

Abstract

The present application belongs to the technical field of watermelon and sunflower cultivation, and relates to a cultivation method for watermelon interplanting sunflower to save cost and increase efficiency, which comprises the following steps: selecting suitable plots, early ploughing and applying compound base fertilizer, making ridges, laying drip irrigation belts and film mulching treatment; watermelon seedlings are cultivated in early spring, and are planted in early May, adopting arched shed heat preservation and matching precise water and fertilizer management; sunflower is interplanted on the watermelon ridge in mid-June, and is sown by hole planting after seed soaking or germination, and a simplified fertilizer application strategy is implemented. The present application realizes efficient use of light, heat and land resources through space-time coupling and three-dimensional planting; production cost is reduced by using facility sharing and fertilizer aftereffect; the two crops are ecologically complementary, which helps to alleviate the continuous cropping obstacles and improve the system stability. The cultivation mode realizes significant increase of unit area output value under the premise of basically not increasing main means of production, and has the comprehensive advantages of cost saving, efficiency increase and ecological friendliness.

Description

Technical Field

[0001] This invention belongs to the field of watermelon and sunflower cultivation technology, and relates to a cultivation method for intercropping watermelon with sunflower to reduce costs and increase efficiency. Background Technology

[0002] Watermelons and sunflowers are both important economic crops and are widely cultivated in my country. Currently, watermelon cultivation generally employs intensive cultivation methods such as monoculture, mulching, and seedling transplanting to aim for earlier market entry and higher yields. Sunflowers, on the other hand, are often grown as oil crops or ornamental crops, either monoculture or in rotation with other field crops. However, traditional monoculture cultivation methods have the following significant drawbacks:

[0003] 1. Low utilization rate of land and light and heat resources: Watermelon plants are small in the early stages of growth, resulting in low ground coverage and a large amount of land and light energy remaining idle until the vines close the canopy. Sunflower seedlings also grow relatively slowly. Monoculture cannot make full use of land and light and heat resources during the growing season in terms of both time and space, resulting in the annual output potential per unit area not being fully tapped.

[0004] 2. A single planting system leads to high risks of continuous cropping obstacles. Watermelons are particularly susceptible to damage from continuous cropping, which can cause soil nutrient imbalances and exacerbate pests and diseases, severely hindering sustainable production. Traditional solutions often involve crop rotation with rice or corn, but for regions where melons are the primary source of income, this means low land turnover and limited economic benefits. While sunflowers are less demanding in terms of soil requirements, long-term monoculture is also detrimental to soil health.

[0005] 3. Monoculture systems have simple biodiversity, weak resilience, are more prone to outbreaks of specific pests and diseases, rely heavily on chemical control, and are detrimental to ecological balance and green production. Summary of the Invention

[0006] To address the above problems, this invention provides a cost-effective and efficiency-enhancing cultivation method for intercropping watermelon with sunflower, specifically including the following steps:

[0007] Step 1: Select a plot of land that has not been planted with cucurbit crops for 5-8 years and has fertile soil as the planting field. Plow the land and apply base fertilizer one year before planting. Then, make ridges, set up drip irrigation tape, and cover the ridges with mulch. The ridges should be 1.3m wide, 18-22cm apart, and 20-25cm high. Use 1-2 drip irrigation tapes per ridge and cover the mulch with 0.9-1.1m wide mulch.

[0008] Preferably, the base fertilizer includes 50-100 t / ha of well-rotted manure, 100-200 kg / ha of superphosphate, 200-300 kg / ha of diammonium phosphate, 150-200 kg / ha of potassium sulfate, and 100 kg / ha of oilseed cake.

[0009] Preferably, if the main purpose of mulching the raised beds is to control weeds, black mulch should be used; if the main purpose is to raise the temperature in the early stages, white mulch should be used.

[0010] Step 2: Fill the seedling substrate into 10cm×(10-12)cm biodegradable nutrient pots, leaving a 1-1.5cm gap from the top edge of the pot. Water thoroughly (or water until the moisture content of the nutrient soil reaches 85%). Spray with a 500-fold dilution of metalaxyl-mancozeb fungicide and a 1000-fold dilution of high-efficiency cyhalothrin insecticide, mixed and applied. The dosage of the pesticide solution is 30-40kg / mu. Watermelon seeds, after being dried, soaked, disinfected, and germinated, are sown into the seedling substrate at the end of March to the beginning of April, 1 seed / pot. Cover with 0.8cm of soil after sowing.

[0011] Preferably, the seedling substrate is composed of river silt, well-rotted sheep manure, and furnace ash in a volume ratio of 5:4:1; or it is composed of herbicide-free field soil, sheep manure, well-rotted woodpile bottom soil, and furnace ash in a volume ratio of 4:3:2:1, wherein the well-rotted woodpile bottom soil can also be replaced with humus; most preferably, 0.5 kg / m³ of humus is added to the seedling substrate. 3 The preferred high-quality soil is garden soil that has not been planted with solanaceous or cucurbitaceous crops, or soil that has been planted with onions or garlic.

[0012] Preferably, the drying process involves drying the watermelon seeds in the sun for 2-3 days and then replanting them 8-12 times.

[0013] Preferably, the soaking treatment involves mixing watermelon seeds with water at a volume ratio of 1:3 and soaking for 8-10 hours.

[0014] Preferably, the disinfection process involves placing watermelon seeds in a mesh bag and repeatedly rubbing them inside the bag to remove the thin film on the seed surface. Then, the seeds are treated with fungicide No. 1 developed by the Chinese Academy of Agricultural Sciences. Generally, 2.5 ml of fungicide No. 1 is diluted in 1250 ml of water, and the watermelon seeds are soaked for 30 minutes, followed by rinsing five times with clean water.

[0015] Preferably, the germination treatment involves wrapping and sealing watermelon seeds in a damp towel or gauze with 80% moisture content, germinating them at 25-30℃ for 48 hours, and rinsing them every 8-12 hours. Once 80% of the seeds show signs of sprouting, they are ready for sowing.

[0016] Step 3: During seedling cultivation, maintain a daytime temperature of 25-28℃ and a nighttime temperature of 18-20℃. After the true leaves unfold, maintain a daytime temperature of 25-30℃ and a nighttime temperature of 15-20℃ (preferably 18-20℃ in the first half of the night and 15-18℃ in the second half of the night). Provide 10-12 hours of sunlight during the day. When the moisture content of the seedling substrate is ≤50%, water until the water holding capacity is 80%. Before the 2-leaf-1-heart or 3-leaf-1-heart stage, spray the leaves with a 0.2-0.3% potassium dihydrogen phosphate solution 2-3 times every 3-5 days, at a rate of 30 kg / mu.

[0017] Step 4: 3-5 days before transplanting watermelon seedlings, irrigate the field to 80% moisture content. Set up planting holes with a plant spacing of 1.4-1.5m. Transplant the watermelon seedlings along with their nutrient pots into the planting holes in early May, at a density of 5000-5200 plants / ha. After transplanting, irrigate until saturated and set up an arched film with an arch height of 70cm, a film width of 2.5m, and a film thickness of 1mm. 3-5 days after transplanting, when the temperature inside the film is >45℃, ventilate to lower the temperature to 32℃. Afterward, when the temperature inside the film is ≥30℃, ventilate to lower the temperature to 28℃.

[0018] Step 5: After the seedlings have recovered from transplant shock, water them to 80% water holding capacity. After the seedlings sprout new shoots, apply a vine-stretching fertilizer with the water, using 5 kg / mu of ammonium sulfate with a nitrogen content of 21%. Control fertilizer and water during the budding stage. If the leaves do not wilt, do not water or fertilize until the young melons have set. Then water until the soil is saturated and apply a balanced NPK fertilizer with the water. From the time the young melons have set until they are ready for planting, water them every 2-3 days until the soil is saturated. Apply N, P, and K water-soluble fertilizer every 5-7 days for a total of 2-3 times, using 5-8 kg / mu each time. The NPK content for the first to third applications is 20-8-15, 10-8-20, and 5-10-30, respectively. From the time they are ready for planting until maturity, spray the leaves twice every 3-5 days with a 0.3-0.5% potassium dihydrogen phosphate solution, using 30-45 kg / mu each time.

[0019] Step 6: After sun-drying and soaking, sunflower seeds are sown in holes on the seedbed in mid-June. Sowing is done using a seed-piercing device or by removing the film. 1-3 seeds per hole, with a plant spacing of 0.5-0.7m. Cover the seeds with 3-5cm of soil after sowing. Thin the seedlings when they have 2 true leaves, and finalize the seedlings when they have 4 true leaves, ensuring 1-1.4 plants per hectare.

[0020] Preferably, the sun-drying treatment involves sun-drying the sunflower seeds for 2-3 days, during which time the seeds are turned over 8-12 times.

[0021] Preferably, the soaking treatment involves mixing sunflower seeds with water at a volume ratio of 1:3 and soaking for 6-8 hours.

[0022] Step 7: Apply nitrogen fertilizer 1-2 times throughout the sunflower's growth period, at a rate of 100 kg / ha.

[0023] Preferably, the nitrogen fertilizer is ammonium sulfate or urea.

[0024] The present invention has the following advantages:

[0025] (1) Significantly improves the efficiency of land and light and heat resource utilization. This invention precisely designs crop rotation, with watermelons being transplanted in early spring to utilize early light and heat resources for growth; when the watermelons enter the middle and late stages of growth, sunflowers are intercropped on the raised beds. At this time, although the watermelon plants have taken shape, they have not yet completely withered, and the sunflower seedlings require relatively less light and their growth points point upwards, thus forming a staggered growth pattern in vertical space. When the sunflowers are in vigorous growth in the middle and late stages, the watermelons are nearing the end of harvest, and the conflict between the two during their coexistence period is small. The precise timing arrangement allows the same piece of land to sequentially undertake the high-efficiency production periods of two crops within one growing season, greatly extending the green coverage time and photosynthetic production time of the land. Watermelons grow prostrate, while sunflowers grow upright, forming a low-to-high three-dimensional group structure. This structure is conducive to making fuller use of light, air, and soil space at different levels, reducing resource competition, and increasing the total biomass and economic income per unit area.

[0026] (2) Effectively alleviates continuous cropping obstacles, promotes farmland ecological health and sustainable production. Sunflowers have well-developed root systems, and the depth and range of nutrient and water absorption differ from those of watermelons. This helps to activate and utilize deep soil nutrients that watermelon roots have not fully contacted, reducing soil nutrient fixation and loss. Intercropping the two crops changes the rhizosphere microecological environment, which may affect the soil microbial community structure through the interaction of root exudates, inhibiting the accumulation of watermelon-specific soil-borne pathogens, thereby reducing the risk of continuous cropping diseases such as watermelon wilt.

[0027] (3) As a nectar source plant, sunflowers can attract a large number of pollinating insects such as bees during their flowering period. This not only helps them to pollinate and bear fruit, but also provides a richer pollination medium for watermelons (especially varieties that need pollination), thereby increasing the fruit setting rate and marketability of watermelons and reducing the cost of artificial pollination.

[0028] (4) This invention requires uniform preparation of beds, laying of drip irrigation tape, and mulching before planting. These infrastructure investments are made once and serve both watermelon and sunflower crops, avoiding repeated investment. The drip irrigation technology itself can significantly save irrigation water and improve fertilizer utilization. Watermelon requires a large amount of fertilizer, especially base fertilizer. The intercropped sunflower grows in soil that has been adequately fertilized with base fertilizer. During its growth period, it only needs to be supplemented with nitrogen fertilizer 1-2 times, and the amount is low. This makes full use of the fertilizer aftereffects of the previous watermelon crop, reduces the input of special fertilizers for sunflower planting, and lowers the overall amount of chemical fertilizer used.

[0029] (2) This invention achieves additional yields (oilseeds or flower heads) from sunflowers through intercropping without significantly increasing the main production resources (land, infrastructure), resulting in a total output value per unit area that is significantly higher than that of watermelon monoculture. Even with moderate sunflower yields, the resulting income is almost entirely incremental, greatly improving land productivity. The diversification of planting structure mitigates market and natural disaster risks. If the watermelon market is unfavorable or production is reduced due to climate disasters, the income from sunflowers can serve as an important supplement, ensuring farmers' basic income and enhancing the resilience and stability of agricultural production. Detailed Implementation

[0030] The technical solutions in the embodiments of the invention are described clearly and completely below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0031] Example 1

[0032] Experimental location: Heishui Village, Heishui Town, Taonan City, Baicheng City, Jilin Province

[0033] Experiment period: 2023-2025.

[0034] Experimental varieties and yields: The watermelon variety was Aihua No. 2, and the sunflower variety was Youkui T339. The planting area was 2.5 hectares. The specific yields and output values ​​are shown in Table 1-2.

[0035] The specific experimental steps are as follows:

[0036] Step 1: The land is plowed and basal fertilizer is applied one year before planting. Then, the following steps are taken: making beds, setting up drip irrigation tape, and covering the beds with mulch. The beds are 1.3m wide, 18-22cm apart, and 20cm high. There are 2 drip irrigation tapes per bed, and the mulch film is 1.1m wide.

[0037] The base fertilizer includes 80 t / ha of well-rotted manure, 150 kg / ha of superphosphate, 200 kg / ha of diammonium phosphate, 200 kg / ha of potassium sulfate, and 100 kg / ha of oilseed cake.

[0038] Step 2: Fill the seedling substrate into a 10cm×10cm biodegradable nutrient pot, leaving a 1-1.5cm gap from the top edge of the pot. Water the pot, spray with fungicide and insecticide. After the watermelon seeds have been sun-dried for 3 days, soaked in water for 8 hours, disinfected with fungicide No. 1, and wrapped in a damp towel at 28℃ for 48 hours to germinate, they are sown into the seedling substrate on March 25, 1 seed per pot. Cover the seeds with 0.8cm of soil after sowing.

[0039] The seedling substrate consists of river silt, well-rotted sheep manure, and furnace ash in a ratio of 5:4:1, with 0.5 kg / m³ added. 3 diammonium phosphate.

[0040] Step 3: During seedling cultivation, maintain a daytime temperature of 25℃ and a nighttime temperature of 18℃; after the true leaves unfold, maintain a daytime temperature of 28℃, a first half-night temperature of 20℃, and a second half-night temperature of 16℃; provide 10-12 hours of light during the day and 0 hours of light at night; when the moisture content of the seedling substrate is ≤50%, water until saturated; before the 2-leaf-1-heart or 3-leaf-1-heart stage, spray the leaves with a 0.2% potassium dihydrogen phosphate solution every 4 days, using 15 kg per acre.

[0041] Step 4: 5 days before transplanting watermelon seedlings, water the field until the soil is saturated. Set up planting holes with a plant spacing of 1.5m. Transplant the watermelon seedlings along with their nutrient pots into the planting holes in early May, at a density of 5000 seedlings / ha. After transplanting, water the field until saturated and set up an arched film with an arch height of 70cm, a film width of 2.5m, and a film thickness of 1mm. 3 days after transplanting, when the temperature inside the film is >45℃, ventilate to lower the temperature to 32℃. After that, when the temperature inside the film is ≥30℃, ventilate to lower the temperature to 28℃.

[0042] Step 5: After the seedlings have recovered, water them until saturated. After the seedlings sprout new shoots, apply a vine-extending fertilizer with the water, using 5 kg / mu of ammonium sulfate with a nitrogen content of 21%. Control fertilizer and water during the budding stage until the young melons have set, then water again and apply a balanced NPK fertilizer with the water. After the young melons have set and are ready for planting, water them every 3 days until the soil is saturated, and apply N, P, K water-soluble fertilizer every 7 days for a total of 3 applications, each time using 7 kg / mu. The NPK content for the first to third applications is 20-8-15, 10-8-20, and 5-10-30, respectively. From planting to maturity, spray the leaves twice every 3-5 days with a 0.3-0.5% potassium dihydrogen phosphate solution, each time using 30-45 kg / mu. From seed setting to maturity, spray the leaves twice every 5 days with a 0.3% potassium dihydrogen phosphate solution (30 kg / mu each time). Use bees for pollination (5 hives / ha). On cloudy days, artificial pollination can be used to assist pollination. Ensure that each vine produces fruit of uniform size and no empty vines. Focus on fruit setting on the main vine, selecting the second and third female flowers on the main vine, with the third node being the primary site for fruit setting.

[0043] Step 6: Sunflower seeds are sun-dried for 2 days, turning them over 8 times during this period. They are then mixed with water at a volume ratio of 1:3 and soaked for 8-10 hours. In mid-June, they are sown in holes on the seedbed at a density of 1-3 seeds per hole, with a plant spacing of 0.6m. After sowing, the seeds are covered with 4cm of soil. Thinning is done when the seedlings have 2 true leaves, and final thinning is done when the seedlings have 4 true leaves, ensuring a density of 13,000 plants per hectare.

[0044] Step 7: Apply ammonium sulfate twice during the entire growth period of sunflowers, at a rate of 100 kg / ha. Use bees for pollination, with 3 beehives / ha. Perform the first artificial pollination 3 days after flowering (when 70% of the plants in the field are in bloom), and then perform artificial pollination once every 3 days thereafter, for a total of 3 times. Pollination should be carried out every day from after the morning dew until 11:00 am and after 3:00 pm.

[0045] Table 1. Watermelon yield and output value (2.5 ha)

[0046] 2023 2024 2025 Planting date May 7 May 5 May 8 Harvest date July 15 July 12 July 16 Total output (10,000 kg) 12.5 14.0 15.0 Equivalent yield (10,000 kg / ha) 5.0 5.6 6.0 Total Revenue (Ten Thousand Yuan) 15.75 14.0 19.5 Equivalent income (ten thousand yuan / ha) 6.3 5.6 7.8

[0047] Table 2. Sunflower Yield and Output Value (2.5 ha)

[0048] 2023 2024 2025 Planting date June 20 June 18 June 16 Harvest date September 30 September 30 September 29 Total output (kg) 3000 3125 3750 Equivalent yield (kg / ha) 1200 1250 1500 Total Revenue (Ten Thousand Yuan) 3.0 3.75 3.75 Equivalent income (ten thousand yuan / ha) 1.2 1.5 1.5

[0049] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A cultivation method for intercropping watermelon with sunflower to reduce costs and increase efficiency, characterized in that, include: Step 1: Select a plot of land that has not been planted with cucurbit crops for 5-8 years as the planting field. The land is plowed and basal fertilizer is applied the year before planting. Then, the following steps are taken: making ridges, setting up drip irrigation tape, and covering the ridges with mulch. Step 2: After the watermelon seeds are dried, soaked, disinfected and germinated, they are raised into seedlings in late March to early April. The watermelon seedlings are sown in holes on the seedbed in early May at a density of 5000-5200 plants / ha. An arched film is set up. When the temperature inside the film is >45℃ 3-5 days after transplanting, ventilation is provided to lower the temperature to 32℃. After that, when the temperature inside the film is ≥30℃, ventilation is provided to lower the temperature to 28℃. Step 3: After sun-drying and soaking, sunflower seeds are sown in holes on the seedbed in mid-June, 1-3 seeds per hole, with a plant spacing of 0.5-0.7m. After sowing, cover with 3-5cm of soil. Thin out seedlings when they have 2 true leaves, and finalize the seedlings when they have 4 true leaves, ensuring 10,000-14,000 plants per hectare.

2. The cultivation method for intercropping watermelon and sunflower according to claim 1, characterized in that, The base fertilizer mentioned in step one includes 50-100 t / ha of well-rotted manure, 100-200 kg / ha of superphosphate, 200-300 kg / ha of diammonium phosphate, 150-200 kg / ha of potassium sulfate, and 100 kg / ha of oilseed cake.

3. The cultivation method for intercropping watermelon and sunflower according to claim 1, characterized in that, The bed width in step one is 1.3m, the bed spacing is 18-22cm, the bed height is 20-25cm, there are 2 drip irrigation tapes per bed, and the mulch film is 1.1m wide.

4. The cultivation method for intercropping watermelon and sunflower according to claim 1, characterized in that, The drying treatment in step two involves drying watermelon seeds in the sun for 2-3 days and turning them over 8-12 times. The soaking treatment involves mixing watermelon seeds with water at a volume ratio of 1:3 and soaking for 8-10 hours. The disinfection treatment involves removing the thin film on the surface of the watermelon seeds and disinfecting them according to the instructions of fungicide No. 1 developed by the Chinese Academy of Agricultural Sciences. The germination treatment involves wrapping and sealing the watermelon seeds in a damp towel or gauze with 80% moisture content, germinating them at 25-30℃ for 48 hours, and rinsing them every 8-12 hours. They can be sown when 80% show signs of sprouting.

5. A cultivation method for intercropping watermelon and sunflower according to claim 1, characterized in that, The seedling raising operation described in step two is as follows: fill the seedling substrate into biodegradable nutrient pots, water, and spray fungicide and insecticide. Spray with a 500-fold dilution of metalaxyl-mancozeb fungicide and a 1000-fold dilution of lambda-cyhalothrin insecticide, mixed and applied at a dosage of 30-40 kg / mu. Sow watermelon seeds in the seedling substrate, 1 seed / pot, and cover with 0.8 cm of soil after sowing. During seedling raising, the daytime temperature should be 25-28℃ and the nighttime temperature should be 18-20℃. After the true leaves unfold, the daytime temperature should be 25-30℃ and the nighttime temperature should be 15-20℃. The daytime light exposure should be 10-12 hours. When the moisture content of the seedling substrate is ≤50%, water until the water holding capacity is 80%. Before the 2-leaf-1-heart or 3-leaf-1-heart stage, spray the leaves with a 0.2-0.3% potassium dihydrogen phosphate aqueous solution 2-3 times every 3-5 days.

6. A cultivation method for intercropping watermelon and sunflower to reduce costs and increase efficiency according to claim 5, characterized in that, The seedling substrate is composed of river silt, well-rotted sheep manure, and furnace ash, in a volume ratio of 5:4:

1.

7. A cultivation method for intercropping watermelon and sunflower according to claim 6, characterized in that, Add 0.5 kg / m³ to the seedling substrate. 3 diammonium phosphate.

8. A cultivation method for intercropping watermelon and sunflower according to claim 1, characterized in that, In step two, apply vine-promoting fertilizer with water after the seedlings have shaken off the top; control watering during the budding stage, do not water if the leaves do not wilt, and continue watering until the young melons have set, then apply a balanced NPK fertilizer with the water; after the young melons have set and are ready for fruit setting, apply plenty of water and fertilizer to promote fruit growth; from the time the melons are ready for fruit setting until maturity, spray the leaves twice every 3-5 days with a 0.3-0.5% potassium dihydrogen phosphate solution.

9. A cultivation method for intercropping watermelon and sunflower to reduce costs and increase efficiency according to claim 1, characterized in that, The sun-drying treatment in step three involves sun-drying the sunflower seeds for 2-3 days and turning them over 8-12 times; the soaking treatment involves mixing the sunflower seeds with water at a volume ratio of 1:3 and soaking them for 6-8 hours.

10. A cultivation method for intercropping watermelon and sunflower according to claim 1, characterized in that, In step three, apply nitrogen fertilizer 1-2 times throughout the sunflower's growth period, at a rate of 100 kg / ha.