Sweet Potato Fertilization Technology
Sweet potato has wide adaptability and strong resistance, and it is one of the high-yield and stable food crops. In order to obtain high yield of sweet potato, it is necessary to give enough fertilizer at the right time to meet the demand for nutrients for the normal growth of sweet potato at each growth stage. Now the requirements of sweet potatoes and fertilization techniques are described below for reference. 1. Fertilizer Requirements for Sweet Potatoes The requirements for sweet potatoes for fertilizers are the most with potash fertilizer, followed by nitrogen fertilizer and less with phosphate fertilizer. The needs of sweet potatoes for the three elements differ depending on the growing period. The absorption of potassium from planting to harvest is higher than that of nitrogen and phosphorus, especially in the period of root swelling; nitrogen fertilizer absorbs more during the growth period of stems and leaves, and absorbs less during the expansion of tuberous roots; phosphorus fertilizer absorbs less in the middle period of stem and leaf growth. , but absorb more during the root swelling. Therefore, basal fertilizers should be applied adequately to top-dress fertilizers and increase phosphorus and potassium fertilizers. 2, fertilization techniques 2.1 Shizu base fertilizer should be farm-based fertilizer, supplemented by fertilizer, farmyard fertilizer to fully decomposed. The amount of basal fertilizer generally accounts for 60% to 80% of the total amount of fertilizer. The specific fertilization amount is 667 square meters. The plot will produce more than 4000kg of land. Generally, it will produce 5000 to 7500kg of base fertilizer, and 667 square meters will produce 2500 to 4000kg of land. Generally, it will use 3000 to 4000kg of base fertilizer. At the same time, it can be used with calcium superphosphate 15 ~ 25kg, plant ash 100 ~ 150kg, ammonium bicarbonate 7 ~ 10kg and so on. The fertilization method adopts the method of concentrated deep application and combination of coarse and fine fertilizers. 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. 2.2 According to local conditions, top dressing should be based on the appearance and needs of different growth stages to determine the top dressing period, type, quantity and method, so that a reasonable top dressing can be achieved. Lifting the seedlings to raise the seedling fertilizer is the deficiency of supplementing the base fertilizer and the slow effect of the base fertilizer. Generally, the quick fertilizer is chased. After chasing the fat, 3 to 5 days after planting, the seedlings are combined with seedlings to make seedlings. A small hole is opened at the lateral side of the seedling at 7 to 10 cm, and a small amount of chemical fertilizer (1.5 to 3.5 kg per 667 square meters) is applied. Watering cover is applied immediately after application. Soil can also be fed with 1% urea water; rooting the seedlings at the latest can be carried out before and after the planting period at the latest two weeks after planting. Apply 1.5 to 5 kg of nitrogen fertilizer per 667 square meters. , Large plants and less plants, do not top-dressing under drought conditions.Strong potato plants branching and potato stage, the formation of underground root network, potato block began to expand, suction fertility, to increase leaf area, improve the efficiency of photosynthetic production, as soon as possible Fertilizer, in order to achieve the purpose of strong potato, fast long and steady growth.Topdressing time in the 30 ~ 40d after planting.The amount of fertilizer varies due to potato, seedling potential, growth potential difference of multiple applications, chasing ammonium sulfate per 667 square meters 7.5 ~ 10kg or urea 3.5" 4.5kg or ammonium nitrate 4.5 ~ 6kg, potassium sulfate 10kg or plant ash 100kg; growth is better, the amount can be reduced by half. The amount of nitrogen applied to raise the seedlings or afforestation time is larger. The strong strains of potato grown in the strong plants should be dominated by phosphorus and potassium, supplemented by nitrogen fertilizer; otherwise, both nitrogen and potassium should be weighted together to attack the strong pods and the 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 cultivating after application, labor economy, and effective. 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 using potassium sulfate, 667 square meters Shi 10kg, such as using plant ash 100 ~ 150kg. Grass ash can not be mixed with nitrogen and phosphorus fertilizers, pay attention to separate application. Water can be used as soon as possible when fertilizing. The land where the crack fertilizer is prone to premature decay, the land where the stems and leaves are growing poorly and the lands that are insufficiently sculpted in the previous few times, when the yam soil is cracked and sewn, a small amount of available nitrogen fertilizer is applied, and there is a certain increase in production. effect. Generally, every 667 square meters chase 4~5kg of ammonium sulfate and water 500kg; or use human excrement 200~250kg, dilute 600~750kg, and apply irrigation along the crack. Outside the roots, the stage of the expansion of the top-fertilizer is about 90 to 140 days after planting. It is the late stage of the growth of sweet potato. Spraying phosphorus and potash fertilizer can not only increase production, but also improve the quality of the tuber. Use 2% to 5% of calcium superphosphate solution or 1% of potassium phosphate solution or 0.3% of potassium dihydrogen phosphate solution or 5% to 10% of filtered grass ash, spraying after 3pm, every 667 square meters Spray 75 ~ 100kg. Spray once every 15 days for a total of 2 sprays. 3 Precautions Sweet potatoes are chlorine-free crops and cannot contain fertilizers containing chlorine. Ammonium bicarbonate is not suitable for spreading and surface application, and it can be used as deep-mixed fertilizer particles.