Detailed Explanation of Multi-Layer Covered Seedling Cultivation Technology for Cucumbers in Spring Greenhouses
1. Do not arbitrarily change the light-receiving angle of the greenhouse. The angle of the solar greenhouse currently used for cucumber cultivation has been scientifically verified over a long period. Its north-south span, height, and rear slope angle should not be arbitrarily changed. 2. Do not apply concentrated fertilizer at transplanting. Various chemical fertilizers, especially nitrogen fertilizers, under humid and high-temperature conditions, will produce large amounts of...
I. Greenhouse structure. The greenhouse span is best at 6-8 m. Install the greenhouse film in early November. Set up a 1.5 m small arch inside the greenhouse... II. Preparation of nutrient soil. Take 60% fertile field soil that has never been planted with Cucurbitaceae crops, and 40% decomposed organic fertilizer. For each cubic meter, add 15 kg of decomposed, finely crushed chicken manure, 3 kg of superphosphate, 2 kg of urea, 1-1.5 kg of potassium sulfate, and 100 g of 50% carbendazim can be added per cubic meter of soil. Mix well and set aside.
III. Sowing
1. Seed selection: Choose varieties with disease resistance, strong stress resistance, good commercial traits, and high yield. For winter-spring solar greenhouse cultivation, Jinchun No. 3, Jinyou No. 3, and Leiyu Baijintiao can be selected; for spring open-field cultivation, Leting Qiugua, Cuiyu, Tangshan Qiugua, etc. can be selected.
2. Seed treatment: Soak the seeds in 55°C warm water for 10-15 minutes, stirring constantly until the water temperature drops to room temperature, then soak for another 3-4 hours. Then rub and wash the seeds repeatedly, rinse the mucus clean with clear water, then dry and germinate. This can prevent scab, anthracnose, viral disease, and sclerotinia. Soak the seeds in 500 times diluted 50% carbendazim solution for 1 hour, then remove, wash clean, and germinate to prevent fusarium wilt and scab. Wrap the treated seeds in a wet cloth and germinate at 25-30°C for 1-2 days. When the seeds "show white tips," place them at 0-20°C for another 1-2 days to germinate.
3. Sowing: Sow when most seeds have germinated. For solar greenhouse winter-spring crop, sow in early to mid-January; for winter crop, sow from late September to early October. For open-field spring crop, sow from mid-March to early April; for autumn crop, sow from late June to early July. One day before sowing, water the seedbed soil thoroughly once. Before sowing, thinly spread a layer of fine moist soil on the bed surface, then mix in a little fine sand so it can be spread evenly. The sowing rate per mu is between 140-160 g. After sowing, cover the bed surface with a 1 cm thick layer of thiophanate-methyl medicated soil, then cover with plastic film to keep warm and moist.
IV. Seedbed management
1. Management of young seedlings: After sowing, keep the small arch film tightly closed during the day. At night, cover it with a layer of thick straw and old greenhouse film. (Cover early and uncover late as appropriate.) During this period, the natural maximum daytime greenhouse temperature reaches 25-30°C, which is relatively suitable, and ventilation is not necessary. After emergence, remove the plastic film. After sunrise during the day, remove the old greenhouse film and straw mat, then later uncover the small arch film to enhance light. At 4 p.m., cover the small arch, straw mat, and old greenhouse film. To prevent leggy growth, after emergence the temperature should be kept slightly lower, controlled at about 20°C during the day and 8-15°C at night. Reduce the temperature slightly 3-5 days before pricking out, so that the seedling leaves are thick, the leaf color is dark green, the root system is well developed, and the seedlings recover quickly after pricking out. When the young seedlings grow to 2 true leaves, prick them out in time. Pricking out too early is inconvenient to operate, and too late makes it easy to damage roots when lifting seedlings, affecting the survival rate after pricking out. Water the seedbed the day before pricking out, lift the seedlings the next day, plant them separately into nutrient pots, and water thoroughly with thiophanate-methyl solution to prevent seedling-stage diseases.
2. Management after pricking out: After pricking out, to prevent seedling wilting, cover with a small arch for shade during the day. After the seedlings recover, uncover the small arch film during the day, and at night cover the small arch film, straw mat, and old greenhouse film. At this time, keep the daytime temperature at about 28°C and nighttime at 10-18°C, and not lower than 8°C at minimum. If the pot soil is found to be dry, water thoroughly in time on a sunny morning. The seedling age is 40-45 days, and they can be transplanted when they have three leaves and one heart.