Detailed Explanation of Key Cultivation Techniques for Overwintering Eggplant

Overwintering eggplant is a cultivation model for year-round production, supplying the severe winter and early spring markets. Seedlings are raised in early to mid-September, transplanted in mid-November, and harvesting begins in mid-January and continues until June to July of the following year. For this crop, the yield per mu can reach 9,000 kg. At an average market price of 4.0 yuan per kg, the gross income per mu can reach 36,000 yuan. After deducting production costs of 3,800 yuan, a net profit of 32,200 yuan can be obtained.

The main cultivation techniques are as follows: Overwintering eggplant is best grown using grafting, which can greatly improve plant stress resistance, thereby achieving high yields and high-quality produce.

1. Variety selection: Select "Fengyan No. 1" as the scion, with a seeding rate of 50 g per mu, and select "Torubamu" (Solanum torvum) as the rootstock, with a seeding rate of 5 g per mu.

2. Seedling raising: (1) Sowing time: Using the cleft grafting method, rootstock seedlings are sown 15 days earlier than scion seedlings. (2) Seed soaking and germination: Use the variable temperature germination method. (3) Grafting: Graft when rootstock seedlings have grown to 4-5 leaves and scion seedlings have grown to 2-3 true leaves.

3. Transplanting: When seedlings reach 60-70 days of age and the plants have flower buds the size of soybean grains, they can be transplanted. Transplanting uses wide and narrow row cultivation, with wide rows at 80 cm, narrow rows at 60 cm, and plant spacing at 45 cm, giving a planting density of 2,100 plants per mu.

4. Management after transplanting: (1) Temperature management: Generally 25-30°C in the morning, 28-20°C in the afternoon, 20-13°C in the early night, and 13-10°C in the late night. (2) Fertilizer and water management: Appropriately control water in the early stage. When the first fruit (the "door eggplant") reaches the "eye-opening" stage, apply 20 kg of urea per mu along with watering. Once entering the peak fruiting period, water every 7 days and fertilize every half month, applying 30 kg of diammonium phosphate and 20 kg of urea per mu each time.

5. Pruning method: Use the two-stem pruning method.

6. Flower and fruit preservation: Spray flowers with Tomatotone and 4-CPA at 30-50 ppm, and apply 2,4-D at 20-30 ppm to flowers.

7. Disease control: The main diseases of this crop are damping-off and bacterial wilt. He Xiuling