New techniques of early ripening cultivation of Zizania caduciflora covered in greenhouse

First, sow and fix the plant. Selection of ⑴ varieties: the early-maturing varieties of Zizania latifolia with lower pregnancy temperature should be selected, such as Xiaowatai, Xiehongzao, Zhe Zizhao and so on. ⑵ clearing fertilizer: in the middle and last ten days of December, the dead leaves of the aboveground plants were cut off by Qi mud, and the fields were cleaned and burned centrally, so as to reduce the overwintering base of insect population and bacteria. Fields with more weeds can put stagnant water in the dry fields 5-6 days before the shed, and spray 40 kg of water with 10% glyphosate water agent 1 kg. Generally, 3000-5000 kg of rotten organic fertilizer and 45% of 50 kg of ternary compound fertilizer are applied per mu. ⑶ building greenhouse: in warmer areas, Zizania caduciflora basically does not wither during the overwintering period, so it is appropriate to build a greenhouse before entering the frost period, usually around late December; the winter temperature in the Yangtze River basin is relatively low, in order to prevent the pregnancy of young seedlings in the greenhouse, it is appropriate to build a greenhouse in mid-late January, when the temperature is about to rise. ⑷ thinning seedlings: when the new seedlings are about 30 cm high, keep 15-20 strong seedlings in the periphery of each Zizania caduciflora pier, remove other seedlings on the pier, and press the mud block to the center of the Zizania caduciflora pier at the same time. It is appropriate to control the basic seedlings at about 35000 per mu. Second, water and fertilizer management. During the growth of Zizania caduciflora, the water level should always be kept at 3-5 cm. In the later stage of pregnancy and expansion, the water level can be properly deepened, the expanded Zizania caduciflora can be submerged, and the process of epidermis light turning green can be delayed, but irrigation should not be premature, otherwise it will easily lead to elongation of shortening stems and jointing, affecting yield and quality. Fertilizer management is mainly "promoting". Generally, 45% ternary compound fertilizer is applied 20-25 kg per mu after thinning seedlings; when 30% of Zizania caduciflora stump has tillers and begins to expand, 45% ternary compound fertilizer 15-20 kg per mu is applied as pregnant Zizania caduciflora fertilizer. Third, temperature control. The greenhouse built a year ago was mainly sealed and insulated during the year. After the Beginning of Spring, the temperature changed sharply, so it was still sealed and insulated at night and checked frequently during the day. When the weather is mild, the two ends of the film should be ventilated and cooled and carbon dioxide should be replenished; in fine weather, when the temperature in the shed exceeds 30 ℃, the edge film and both ends should be ventilated; in case of continuous overcast and rainy weather, ventilation should also be strengthened, which is beneficial to strong seedlings. When the daily average temperature is 20-25 ℃, it is the suitable pregnant temperature for Zizania caduciflora. When the daily average temperature before and after the Qingming Festival reaches more than 15 ℃, the greenhouse film can be removed completely. Fourth, cultivate soil and protect water. The traditional technology adopts the method of deep water irrigation to slow down the speed of green epidermis of Zizania caduciflora. In recent years, Zhejiang Province has popularized the technique of cultivating soil and protecting Zizania latifolia. When it is found that there are tillers in the pier of Zizania latifolia, it should be cultivated to 15-20 cm high with soil between rows, which does not exceed the height of Zizania caduciflora. The cultivation of the soil should be carried out in stages, and one should be cultivated at the same time. Because the plants are pregnant first, the soil should be cultivated at the same time. When it was found that the heart leaves at the top of the tillers of Zizania caduciflora contracted, the pillows on the left and right leaves were harvested at ordinary times. Fifth, pest prevention and control. The main pests of Zizania caduciflora are Chilo suppressalis and Chilo suppressalis. Control methods: first, do a good job of clearing the garden in winter, spray Zizania caduciflora and soil surface with 20% triazophos EC 600 times after cutting off dead plants and residual leaves on the ground, to reduce the overwintering base of borer; secondly, in the growing period of Zizania caduciflora, 700,800 times of 80% fenitrothyl powder or 700,800 times of 27% Gaomike EC were sprayed and killed. The main diseases of Zizania caduciflora are rust, flax spot and sheath blight, which can burn the diseased leaves when clearing the field before the shed, and increase the application of potassium fertilizer to improve disease resistance; when the seedling height is 10-20 cm, 50% carbendazim wettable powder 600 times or 70% mancozeb wettable powder 400 times can be sprayed once, and 2-3 times before pregnancy.