Jilou Village, Yongchang Office, Chengwu County, Shandong Province is a famous watermelon cultivation village. In recent years, with the further development of the agricultural economy, the growing area of ​​watermelons has continued to expand. Chengwu County has started to explore high yield and efficient planting. mode. For early nursery and early colonization, the village uses grafted seedlings to enhance the low-temperature tolerance of watermelons. It is covered with three membranes (a greenhouse membrane, a greenhouse film, and a plastic membrane) to allow the watermelons to be picked and marketed in the middle and late May. The average production value is More than 75,000 yuan/hm2, the cultivation techniques are now described below.
1 nursery
1.1 Variety selection
Choose disease-resistant, low-temperature-resistant, early-maturing, and high-yield varieties. Greenhouse watermelon can be used as early maturing varieties such as Jingxin No.1, Black Beauty, Special Early-maturing Xinhongbao, Xiaolan, Xiuli, Hongxiaoyu, Huang Xiaoyu and other mature 25-28 days.
1.2 stock selection
The selected rootstocks must have good affinity with watermelons. Secondly, the selected rootstocks must have high resistance to watermelon wilt disease, strong low temperature resistance, strong resistance to stress, and no effect on the quality of watermelons. Such as Japan's special election New Tosa, Chaofeng Jin and so on.
1.3 Nutrition Soil Preparation
7 kinds of pastoral soil not used for melon crops, 3 parts of farmyard manure, 1m3 of nutrient soil to add 25 kg of large manure or chicken manure, 1.5 kg of superphosphate, 50% of carbendazim powder 0.5 kg or mancozem Zinc 0.25kg, mix and smash and sifted into the nutrient bowl.
1.4 seed processing
Carry out 50% carbendazim 500 times soaking for 1 hour, or soak 10% trisodium phosphate solution for 20 minutes, then wash the seeds and soak them in warm water for 6-8 hours. 2/3 seeds can be sown.
1.5 suitable sowing
In mid-January, seedlings were planted and the amount of seed used in the field was 0.75 to 1.05 kg/hm2. The rootstock is sown about 5 hours later, and the seed amount is about 3kg/hm2. Each seedling should not be too deep so as to be about 1cm. After the broadcast, small sheds were placed in the greenhouse.
1.6 Seedling Management
After sowing, until the emergence of the seedlings, during the day temperature is controlled at 25 ~ 30 °C, night 10 ~ 18 °C, night or overcast snow blankets blankets, 3 ~ 5d to emerge. After emergence, the seedlings should be exposed to light as much as possible. The daytime temperature should be 20 to 28°C and the nighttime temperature should be 10 to 18°C.
1.7 Grafting Points
The proper period of grafting of watermelon is when the first true leaf is unfolded and the rootstock cotyledon is flat. It is required that the depth of the scion should be 2/3 of the length of the bud, and when planting the rootstock, the depth should not exceed 1/2 of the seedling stem, and should not exceed the root breakage; in order to facilitate healing after injury, the root break of the watermelon should be thorough, and a root cut must be kept .
1.8 Grafting Management
After grafting, the temperature was 25-35°C during the day and 20-25°C during the night. The air humidity was not less than 80%, and it was light-shielded. After 3 days, it gradually transmitted light and returned to normal after 7 days. After the survival, remove the growing point of the rootstock in time. After 15d, the root of the watermelon was cut off. Carbendazim 500 times solution was sprayed before planting to prevent seedling disease.
2 Preparation before planting
2.1 Soil Fertilization
Base fertilizer was applied 15 days before planting, applying high quality organic fertilizer 37.5-45.0t/hm2, cooked cake fertilizer 1500kg/hm2, urea 225-300kg/hm2, diammonium phosphate 375-450kg/hm2, potassium fertilizer 300-375kg/hm2.
2.2 Chemical weeding
In order to effectively control annual grass weeds, preemergence application of Napropamide 1.8 ~ 2.7kg/hm2 or Daldry, Dydramine, Jindur and so on. Black plastic film can also inhibit the growth of weeds.
2.3 Shelf Specifications
Shed steel pipe diameter 3cm, span 10m, center height 3m, a single pipe rack can bear about 300kg, overlying without drip film; greenhouses within 2 sets of juxtaposed bamboo wood shed, covered with no drip film; 7 to 10 days before planting fertilization , Soil preparation, reclaiming, filming, opening a hole, colonization of watermelon seedlings in the hole.
3 colonization
At seedling age 45-50 days, planting was carried out from the end of February to the beginning of March. Colonization was carried out in two lines of high ridge cultivation. Planting spacing 1.6m, ridge width 80cm, ridge height 15cm, ridge middle open 12 ~ 15cm shallow ditch irrigation ditch, ridge planting 2 rows of watermelon, row spacing 50cm, plant spacing 40 ~ 5cm, planting density 210000 ~ 27000 plants / hm2 . In order to avoid rooting after contact of the scion hypocotyl with the soil and affect the grafting effect, grafted seedlings should not be planted too deep. After planting, the scion roots must be cut off.
4 Post-planting management
4.1 Pruning
The pruning should be done strictly under the condition of dense planting in greenhouses, and a double sided vine pruning method on the main side is generally adopted. That is, when the main vine grows to 30-50 cm, the side vines begin to grow. When the side vine grows to 20 cm, a strong side vine is selected and the remaining side vines are removed. Remove tendrils while removing side vines.
4.2 Artificially assisted pollination
Selected to stay the main vine 2 female flowers to stay in the melon, the second female flower grow into a watermelon single fruit weight, melon shape is round, good quality. Artificial pollination should be conducted from 9:00 to 11:00 on sunny days and the effect of artificial pollination should be checked the next afternoon. About 7 days after pollination, the melon has been sitting and it can be used for flooding to promote fruit growth.
4.3 Fertilizer Water Management
The absorption of nitrogen, phosphorus and potassium nutrients during the growth period of watermelon is relatively large. Swelling melon fertilizer should be reapplied, Shiyuan compound fertilizer is 450kg/hm2, potassium sulfate is 150-225kg/hm2, and 0.3% dihydrogen phosphate is sprayed on foliar surface. Potassium 1 times, and sprayed 500 times solution of carbendazim 1 time. Flowering and fruiting control watering, prevent melons from being long and affect melons. After sitting for 15 days, the fruit has a large mouth, applying 75-105kg/hm2 of urea, 45-60kg/hm2 of superphosphate and 150-225kg/hm2 of potassium sulfate ternary compound fertilizer, which can be flushed with water in small ridges. With the constant increase of the outside temperature, the amount of watering should be increased, pouring once every 5 ~ 7d, should not flood irrigation, so as not to crack the melon. Watering stopped 7 days before harvesting.
4.4 Pest Control
The common pests and diseases in watermelon production are damping-off, anthrax, blight, blight, virus disease, aphids, leafhoppers and litmus disease. When watermelon anthracnose, downy mildew, leaf blight, epidemic disease, and sporangial disease occur sporadically, spray 64% antivirus dry-wet powder 400-500 times liquid or DuPont Kelu 600 times liquid or Propolis water 1000 Double fluid, etc.; early stage of wilt disease, immediately with thiophanate-methyl 1000 times or carbendazim 500 times Irrigation roots, 500mL per point of the drug solution, can cure sprue disease; virus disease can be used morphine hydrochloride (virus A ) Or work poison control; aphids can be used 10% imidacloprid 1000 times or 3% acetamiprid 2000 times control.
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