High-yield cultivation techniques for plastic-mulched garlic, plastic-mulched watermelon, and cotton

Suwan Town in Chaohu City is a major cotton-growing town. In order to adjust the cropping structure of cotton fields and increase the multiple cropping index and economic returns, after several years of practice, an efficient intercropping and relay cropping model of plastic-mulched garlic, plastic-mulched watermelon, and cotton has been developed. It not only gives good economic returns, but can also build soil fertility and realize the combination of using the land and maintaining the land; at the same time, it can change the ecological environment and reduce the occurrence of pests, diseases, and weeds.

1. Variety selection. For garlic, use the early-maturing variety Ershui Zao; for watermelon, choose early-maturing superior varieties such as Beimi No. 3, Huami No. 8, and Zhengza No. 7; for cotton, choose superior varieties supplied by the Cotton Research Institute of CAAS, such as Guokangmian No. 1 and 410B insect-resistant cotton, with lint yields of more than 90 kg per mu.

2. Crop rotation arrangement. From late August to early and mid-September of the previous year, sow plastic-mulched garlic at the proper early time; in late March of the following year, raise watermelon seedlings; in late April, transplant them under plastic mulch into the reserved rows in the field; in early and mid-April, raise cotton seedlings in nutrient bowls under double-film; after harvesting garlic bulbs in early and mid-May, transplant the cotton.

3. Planting specifications. The bed surface is 3 m wide, and the ditch is 0.4 m wide. Garlic is sown across the whole bed in 16 rows, with a row spacing of 20 cm and a plant spacing of 5-7 cm, planting about 40,000 garlic plants per mu. Around the Spring Festival, harvest green garlic from a 1 m-wide strip in the middle of the bed for market to free up a belt for planting watermelon; plant watermelon in 1 row, with a plant spacing of 40-60 cm, planting about 600 plants per mu. After harvesting garlic in mid-May, plant two rows of cotton on each of the garlic belts at the edges of the bed, with a row spacing of 80 cm and a plant spacing of 30 cm, planting 2,500 cotton plants per mu.

4. Key cultivation points

1. Garlic: sow from late August to early September. Before sowing, make two preparations in conjunction with plowing: first, apply sufficient base fertilizer at one time, generally applying 3,500-4,000 kg of decomposed high-quality farmyard manure, 50 kg of cake fertilizer, 75-100 kg of NPK compound fertilizer or 25 kg of diammonium phosphate, and 15 kg of potassium chloride per mu; second, select seeds, sun the seeds, and soak the seeds in chemicals to promote germination. After sowing, spray herbicide and then cover with film. At emergence, help the seedlings break through the soil by hand. In mid-November, apply a seedling-promoting fertilizer once together with watering, applying 20 kg of urea or 1,500-2,000 kg of decomposed human and livestock manure per mu. At the same time, pay attention to the control of pests and diseases such as garlic leaf blight, soft rot, and garlic seed maggot.

2. Watermelon: transplant in mid-to-late April. Half a month before planting, turn the soil in the reserved rows and sun the soil clods, clear weeds, and apply deeply 1,500 kg of high-quality farmyard manure, 30 kg of NPK compound fertilizer, and 50 kg of decomposed cake fertilizer per mu. Immediately after planting, water thoroughly to settle the roots, cover with film and release the seedlings, and manage carefully; drain and irrigate rationally, fertilize at the right time, cultivate and loosen the soil, prune and press the vines scientifically, and control pests and diseases.

3. Cotton: transplant cotton in early and mid-May. After transplanting, strengthen management: first, balanced fertilization, apply sufficient base fertilizer, increase phosphorus and potassium fertilizer, apply an appropriate amount of fertilizer for plant development, apply a heavy fertilizer at the flowering and boll stage, apply a general topping fertilizer, and increase fertilizer for boll growth; second, cultivate and weed, clear the ditches and drain water to prevent waterlogging damage; third, prune and remove branches in time to regulate growth; fourth, strengthen pest and disease control: at the seedling stage, focus on controlling pests mainly including corn borer, aphids, and red spider mites; at the flowering and boll stage, control the third and fourth generations of cotton bollworm and pests such as tobacco cutworm. Note that during the period when watermelon and cotton coexist, it is strictly forbidden to use highly toxic pesticides; choose high-efficiency, low-toxicity pesticides or improve application methods to reduce pesticide contamination of watermelon.