This is due to the requirements of the manure law and growth and development characteristics of watermelon. During the whole growth period of watermelon, the absorption of nitrogen, phosphorus and potassium was the most potassium, followed by nitrogen and less phosphorus. According to the Research Institute of Soil and Fertilizers of Henan Academy of Agricultural Sciences from 1987 to 1988, for every 1,000 kilograms of watermelon produced, 2.46 kilograms of nitrogen, 0.9 kilograms of phosphorus pentoxide and 3.02 kilograms of potassium oxide were absorbed. The absorption ratio of the three is approximately 2.73:1:3.36. The absorption of three elements in different growth periods of watermelon is quite different. Generally, the absorption of fertilizers during the germination and seedling stages is very small, accounting for only 0.51% of the total amount of nitrogen, phosphorus and potassium. With the growth of plants, the absorption gradually increased, and the period of extension and assimilating accounted for 18% of the total amount of absorbed nitrogen, phosphorus and potassium. The absorption of various fertilizers increased rapidly after the melons were set aside. During this period, the absorption amount was the most and accounted for nitrogen and phosphorus. 81.49% of total potassium absorption. The absorption of each element in different growth periods of watermelon is also different. Before extending the vine, the absorption of nitrogen is the most, followed by potassium. After the melon, the absorption of potassium is the most, followed by nitrogen. High Pure Baicalein,Baicalein Extract,Cas 491-67-8,Baicalein Extract Powder Shaanxi The River Pharmaceutical Co., Ltd. , https://www.dahepharma.com
In addition, the reproductive growth of watermelon and vegetative growth simultaneously, but before the vine extension period, it is mainly vegetative growth, reproductive growth as vice, the flowering period, the nutritional input center gradually transforms to reproductive growth, after the melon, vegetative growth Gradually weakened and turned into reproductive growth.
The roots of watermelons are well-developed and their ability to absorb fertilizers and water is strong. If the amount of basal fertilizers is too much, it will lead to excessive fertillization in the early stages of fertility. This will inevitably lead to strong vegetative growth and luxuriant foliage, which will worsen indoor lighting conditions and cause difficulties in the conversion of nutrient input centers. It is difficult to seat melons. If the melon buds can't be seated in time, the vegetative growth will be even stronger and the melons will be more difficult! Therefore, in the past, watermelons should be properly controlled to prevent intensive nutrient growth and affect the melons, so the amount of basal fertilizer should not be excessive. After the melons were placed, the nutrient input center had turned to the young melons. At this time, the number of top dressings should be increased, the photosynthetic efficiency should be increased, the dry matter accumulation of the watermelon plants should be increased, and the large melons should be promoted. And need to spray potassium fertilizer from outside the root, alternately spray 0.4% of potassium dihydrogen phosphate and 600 times of Tianda 2116 (special type of guatica fruit), and spray once every 5-7 days for 3-4 times, which can increase The yield can also increase the sugar content of the fruit and improve the quality of the watermelon.
Why shouldn't multi-basal fertilizer be applied in greenhouse watermelon cultivation?