Management of greenhouse vegetables before and after emergence

Before sowing vegetables in greenhouse greenhouses, the seedlings mainly depend on the vegetative growth of the seeds themselves. During this period, sufficient water, high seedbed temperature and good ventilation conditions are required to promote the emergence of seedlings. Under normal circumstances, tomato, eggplant, pepper, cucumber, zucchini, kidney beans and other warm vegetables, seedbed temperature should be controlled at 25 ~ 32 ° C; borage, celery and other cold vegetables, can be controlled at 20 ~ 25 ° C. When the seedbed is a cold bed, the plastic film is sealed after sowing, so that the air is not allowed to pass through, and the humidity is ensured. At night, in order to raise the night temperature, the grasshopper and the mane can be properly covered and exposed at night. When most of the seedlings are unearthed, the mulch is removed and a layer of fine soil is removed from the surface to reduce evaporation of water and reduce bud capping. When the seedlings are unearthed, the soil is squashed or the soil layer is raised.
During the unearthing of the seedlings to the first true leaf exposure, the focus of the seedbed management is to appropriately reduce the nighttime temperature, control the moisture in the seedbed, prevent the embryonic axis from growing, and give the seedlings full light. Within 2 to 3 days of emergence, the high temperature, high humidity and insufficient light are strictly avoided in the seedbed to prevent the formation of "long-legged seedlings". Generally, after most of the seedlings are unearthed, they begin to ventilate during the day and gradually increase the amount of ventilation. The bed temperature of eggplant and pepper decreased to 25~26°C during the daytime, and 14～16°C at night: the temperature of daytime seedling bed of cucumber, zucchini and tomato was controlled at 20°C and 12～14°C at night. Ventilation should not be too urgent to prevent flashing.
At noon on sunny days, the film can be uncovered and a layer of fine dry soil can be removed from the seedbed to protect the seedbed and reduce the humidity of the seedbed. When the seedbed is dry, water can be sprayed to the seedbed to avoid flooding. In addition, it is necessary to extend the illumination time as much as possible to promote the healthy growth of the seedlings.
In addition, it can be sprayed with Dixon 100 times solution or 50% carbendazim 500 times solution; it can also be sprayed with 5 grams of water and 1.5 kilograms of water per square meter to spray the soil around the diseased plant to control the spread of the disease.
How to carry out the preservation of fruit in winter tomatoes The reason why tomatoes fall and fall is very complicated. The flower drop of tomato is mainly related to the growth hormone content in the plant. If the environmental conditions and nutritional conditions are suitable, the development of tomato flower and pollination and fertilization are normal, the growth and development of the fruit is normal, and the amount of auxin formed in the body increases continuously and remains high. Level, generally does not produce falling flowers. If the environmental conditions and nutritional conditions are not suitable, the development of tomato flower and pollination and fertilization are not normal, the growth and development of the fruit is not normal, the amount of auxin formed in the fruit is not promoted, and the low content will produce the phenomenon of falling flowers and fruit.
Cultivating age-appropriate seedlings is the basis for winter tomato flower preservation and fruit conservation. It is difficult to achieve the goal by relying solely on the fruit setting regulator, requiring comprehensive management, timely control of vegetative growth, proper control of vegetative growth, and promotion of reproductive growth to facilitate flowering and fruit setting. At the same time, strengthen the management of fertilizer and water, appropriately reduce the application rate of nitrogen fertilizer, increase the application of phosphorus and potassium fertilizer, and control irrigation during flowering period. It is simple and effective to vibrate plants or shake inflorescences during flowering, and it is also simple and effective to use pollination. On the basis of artificially assisted pollination, the tomato fruit setting regulator is used to treat the inflorescence, and the effect of preserving flowers and fruits is good. Generally, a tomato spirit having a concentration of 50 ppm is used. 0.2% scopolamine was added during the preparation of the fruit setting regulator to prevent gray mold from infecting during flowering and fruit setting. After planting, the temperature should be kept at around 25 °C during the day, and the night temperature should be kept at around 14 °C, but not longer than 8 °C for a long time. Try to keep the plastic film clean and increase the light. At the flowering stage, fertilizers such as potassium dihydrogen phosphate can be sprayed on the foliar surface to promote and promote carbon dioxide fertilization, and attention should be paid to disease prevention. Long seedlings, old and weak seedlings are difficult to prevent falling flowers and deformed fruits in winter. It can be properly colonized early, slow seedlings early, promote root development, and help to winter.