One of the important conditions for sweet potato to achieve high yield is to timely fertilize enough fertilizer to meet the demand for nutrients for the normal growth of sweet potato at each growth stage. So how do you fertilize potato fields? I. Fertilizer requirements for sweet potatoes The requirement of sweet potato for fertilizer is the most with potassium, followed by nitrogen fertilizer, and less with phosphate fertilizer. The demand of sweet potatoes for the three fertilizers varies with the growth period. Potassium absorption from planting to harvesting was higher than that of nitrogen and phosphorus, especially during root enlargement; nitrogen fertilizer absorbed more during the growth period of stems and leaves, less absorbed during root enlargement; and phosphorus fertilizer absorbed less in the middle period of stem and leaf growth. , but absorb more during the root swelling. Therefore, fertilization should be given to the potato field, suitable for early fertilization and increased phosphorus and potassium fertilizers. Second, fertilization technology 1. Apply base fertilizer. Farmhouse fertilizers should be the mainstay, supplemented by chemical fertilizers, and farmyard fertilizers should be fully decomposed. The amount of basal fertilizer generally accounts for 60% to 80% of the total amount of fertilizer. The specific amount of fertilization depends on the production. For plots with a yield of more than 4,000 kilograms per mu, the average amount of Mushi basal fertilizer ranges from 5000 to 7500 kilograms; the plots with a yield of 2500 to 4000 kilograms per kilogram are generally 3,000 to 4,000 kilograms per mu. At the same time, with the application of Mushi into the superphosphate 15 ~ 25 kg, 100 ~ 150 kg of plant ash, ammonium bicarbonate 7 ~ 10 kg. Fertilization method: The combination of concentrated deep application and coarse and fine fertilizer layering. More than half of the basal fertilizer is applied to the bottom layer when deep plowing, and the rest of the basal fertilizers can be applied to the ridge bottom when ridding or when planting. This method can give full play to the role of fertilizer in the absence of fertilizer. The available nitrogen and quick-acting potassium fertilizers in basal fertilizer should be concentrated in the upper layer so that they can be absorbed immediately after the survival. 2. Apply fertilizer to local conditions. According to the appearance and needs of different growth stages, determine the top dressing period, type, quantity and method, so that a reasonable top dressing. Miaomiao fertilizer is to make up for the shortcomings of basal fertilizer deficiency and basal fertilizer effect. Generally, quick-effect fertilizer is applied. After 3 to 5 days after planting, seedlings and seedlings are added for top dressing, and a small hole is opened at 7 to 10 cm below the seedling side. A handful of chemical fertilizers were applied immediately after the application of water and cover soil, and 1% urea water was also used to irrigate the roots; Kilograms, pay attention to small plants and more facilities, large plants and less facilities, do not top-dressing under drought conditions. Branch and potato stage, the formation of underground root network, potato block began to expand, suction fertility, in order to increase the leaf area, increase the efficiency of photosynthetic production, the need for early fertilizer, in order to achieve the purpose of strong potatoes, fast long and steady. Top dressing time is 30 to 40 days after planting. The amount of fertilizer varies depending on the field of potato and seedlings, and the growth potential difference is often 7.5 to 10 kg of ammonium sulphate or 3.5 to 4.5 kg of urea or 4.5 to 6 kg of ammonium nitrate, 10 kg of potassium sulfate or 100 kg of plant ash per mu; Preferably, the amount can be reduced by half. The amount of nitrogenous fertilizer applied to raise the seedlings or planting trees was higher, and the strong planted potato fertilizers should be dominated by phosphorus and potassium, supplemented by nitrogen fertilizers, or weighed together with nitrogen and potassium, respectively to attack strong and sweet potatoes. The high-yield fields with a large amount of basal fertilizer may not be top-dressed, or may only be top-dressed with potash fertilizer. The beginning of tuber is the most suitable opportunity to mediate the three environmental factors of fertilizer, water, and gas. Fertilization at the same time combined with irrigation, timely cultivator after application. Potato fertilizer is mainly potash fertilizer, and the fertilization period is generally 90 to 100 days after planting. The topdressing of potash fertilizer is to increase the potassium content in the leaves, extend the leaf age, thicken stems and petioles, and keep them young; second, increase the photosynthetic efficiency and promote the operation of photosynthetic products; thirdly, stems and leaves and tubers The high ratio of potassium to nitrogen can promote the expansion of tubers. Potato fertilizer such as with potassium sulfate, applied per acre 10 kg, such as the use of vegetation ash Mushi 100 to 150 kg. Plant ash cannot be mixed with nitrogen and phosphorus fertilizers and should be applied separately. Water can be used as soon as possible when fertilizing. Prone to premature failure in the plot, in the stems and leaves long-term growth of the poor growth plots and the first few top-dressing plots, in the cracking joints of yam soil, topdressing a small amount of available nitrogen fertilizer, a certain increase in production. Generally, 4 to 5 kg of ammonium sulfate per mu, 500 kg of water, or 200 to 250 kg of human waste, 600 to 750 kg of water, and irrigation along the cracks. During the expansion of the tuber, 90 to 140 days after the planting, at the later stage of the growth of the sweet potato, the application of phosphorus and potash fertilizer can not only increase the yield but also improve the quality of the tuber. With 2% to 5% of superphosphate calcium leaching solution or 1% of potassium phosphate solution or 0.3% of potassium dihydrogen phosphate solution or 5% to 10% of filtered ash soaking solution, spraying after 3 pm, spraying per acre Apply 75 to 100 kg of fertilizer solution. Spray once every 15 days for a total of 2 sprays. Third, pay attention to matters Sweet potato is a chlorine-free crop, and fertilizers containing chlorine cannot be applied. Ammonium bicarbonate is not suitable for spreading and foliar application, and it can be made into deep-mixed fertilizer particles. Liga-Lok Endo Appliers,Hemolock Clip Applier,Laparoscopic Clip Applier,Hemolock Clip Applicator Qingdao DMD Medical Technology Co., LTD , https://www.conston-tech.com