Double greenhouse watermelon efficient cultivation

Dongtai City, Jiangsu Province was named as the hometown of China's watermelon in 2007. Its greenhouse watermelon planting area of ​​13,600 hectares, annual income of more than 1 billion yuan, significant economic and social benefits.

1. Choosing good varieties and nurturing strong seedlings In recent years, watermelon varieties cultivated in the coastal areas mainly include early spring red jade, Hong Xiaoyu, Huang Xiaoyu, Te Xiaofeng, Xiaolan, etc., with the middle-fruit variety Jingxin No. 1 and Beijing. Xin 2, early good (8424). The melon farmers in the coastal areas generally soaked and germinated in mid-January, and applied electric heating lines (80-100 watts per square meter) and light-matrix trays in seedlings in the middle of January. The temperature and humidity were adjusted during seedling period, and 75% chlorothalonil was timely sprayed. Wettable powder 800 times liquid + 70% thiophanate-methyl wettable powder 800 times, to prevent early spring low temperature and high humidity caused seedling disease. 5 to 7 days before transplanting, moderately hardening seedlings. The seedling age is 30 days. The standard of 2 leaves and 1 heart is used as the planting seedling.

Second, the rational close planting, multi-layer coverage of watermelon should be selected within 3 years of not planted melons and pollution-free sources of sandy loam soil cultivation. Twenty days before planting, double sheds were built to cover the drip-free membrane and increase the temperature. The width of the inner shed is 4.5 meters, the top membrane is 5 meters wide, the skirt is 1 meter wide, the outer shed is 5 meters wide, the top membrane is 6 meters wide, the skirt is 1 meter wide; the inner and outer greenhouses have a 20- to 25-centimeter spacing at the top The distance between the agricultural film is 15-20 cm, the height of the greenhouse is 1.6-1.8 meters, and the length is 50-150 meters. 10 days before planting in the shed to do hoeing and spraying herbicides. It is 2 meters wide and 0.5 meters wide in the middle walkway. 72ml per hectare 100ml or 96% Jindul 50ml or 48% sedative (delladin) 100ml to 40kg water evenly sprayed to prevent weeds, then flatten the film, preheat soil. Double greenhouses + sheds + plastic film covering cultivation of watermelon, in the middle and early mid-February 10 centimeters in the underground 10 °C soil temperature above 12 °C, the minimum temperature of 8 °C above the colonization, 700 ~ 750 per acre colonization, pouring feet slowly Seedling water, seal planting holes, cover a small shed film, close the greenhouse and form a 4 film cover.

Third, the application of basic fertilizer, fertilizer timely cultivation of high-quality pollution-free high-quality watermelon, should adhere to the full application of organic fertilizer, increased phosphorus and potassium fertilizer. The basal fertilizer was changed to the full-scale fertilization method in the past, combined with digging of frozen sorghum before the winter, with 1500-2000 kg of rotten chicken manure per acre, 200-250 kg of cooked cotton cake or cabbage, and turned into the bottom layer; Superphosphate 50 kg, 45% potassium sulfate compound fertilizer 50 kg (KP used). After pollination by the second female flower, when the young melon began to enlarge, it was about 60 cm from the melon root, and 20 kg of urea and 10 kg of potassium sulfate were applied per mu. In the case of persistent dry weather during the expansion of young larvae, we must pay attention to proper watering or drip irrigation under the membrane hose to resist drought. After the first batch of melons were harvested, a further 15 kg of urea and 10 kg of diammonium phosphate were applied under the plastic film in the lower part of the foot under the plastic film in the lower part of the foot. As a relay fertilizer, the growth of the second batch and the third batch of melons was promoted.

Fourth, scientific pruning, artificial pollination Small watermelon early growth is weak, fruit type is small, suitable to stay more vines and more fruit. There are two kinds of pruning methods: one is to leave the main vine pruning method, that is, in addition to leaving the main vine, and then choose to leave the base of 2 to 3 strong cranberry, remove the remaining sub-vine and vine vine, and finally retain 3-4 vine pruning branches The second is the pruning and pruning method. When the main vines are 5 to 6 true leaves, they are picked up. After the vines are pumped, 4 to 5 closely growing vines are grown in parallel and the rest of the vines or vines are removed. The fruit type watermelon adopts a pair of double vine pruning method. In order to increase the commodity rate and fruit setting rate of watermelons, the second female flower is usually selected for artificial pollination, and marks are also required. It is worth noting that large-scale cultivation of red jade watermelon in early spring should be accompanied by the cultivation of watermelon varieties that provide enough pollen for similar growth periods. After watermelon is set, it is necessary to pay attention to fruit thinning. Generally, the first batch of melons should leave one for each strain.

Fifth, adjust the temperature According to the development process of watermelon and weather conditions, timely release, cover film, adjust the temperature within the greenhouse, watermelon seedlings 5 ​​to 7 days after planting, to maintain the daily temperature 28 ~ 30 °C, night temperature 16 ~ 18 °C; After the vegetative growth stage, the daily temperature is maintained at 26 to 28°C and the fruiting period is 30 to 32°C. The minimum temperature at the fruit development and maturation period is 20°C and the maximum is no more than 35°C. It should be noted that when the outside temperature is above 25°C, the apron film can be removed, but the top film of the greenhouse should not be removed so as to avoid the fruit cracking caused by continuous rainy weather.

Six, disease prevention and pest control selection of disease-resistant varieties, pay attention to crop rotation or grafting for root, timely application of 50% carbendazim WP 800 times or 65% more than 100 WP 500 times or 12.5% ​​Weiwei 200 Doubling with roots can effectively prevent blight. Watermelon during the period of squashing, especially in April when it encounters continuous rainy weather, it is necessary to use 45% chlorothalonil smoke agent or 250 grams of 15% procymidone smoke agent per acre for fumigation to control sclerotinia and gray mold; Spray 75% chlorothalonil WP 800 times + 70% thiophanate-methyl wettable powder 800 times to prevent epidemics and anthrax. Once locusts and whiteflies were found to be harmful, 70% precious (imidacloprid) wettable powder 5000 times solution + 0.5% chlorimidine (avermectin) EC was sprayed at 1000 times.

VII. Timely Harvesting of Watermelon In spring cultivation, the first batch of melons matures within 32 to 35 days after pollination, and the second batch of melon matures about 25 days after pollination. After the watermelons are picked, they are graded, branded, bagged, and packaged.