Rational fertilization in Sorghum cultivation

Sorghum has wide adaptability to soil and strong fertility. When planted on sandy loam with rich organic matter and high fertility, sorghum is easy to get high yield. In lean dry land, lack of phosphorus and low potassium, it is necessary to apply more fertilizer in order to get a good harvest. The plant of sorghum at seedling stage is small, and the amount of fertilizer needed is not much, but it is more strict. From jointing to flowering, the plant grows vigorously, and the distribution center of nutrients changes from stems and leaves to young spikes from jointing to flowering, and finally stored in the panicle to form grains. Therefore, ensuring adequate nutrition supply at this time is the basis of high yield. From flowering to maturity, the nutrition supply of nitrogen, phosphorus and potassium directly affects the grain filling and ripening of sorghum. Appropriate amount of nitrogen supply can accelerate grain filling and increase the protein content in grains, but too much too late will also lead to late ripening and reduce yield and quality. It is generally required to apply 2000 to 3000 kilograms of organic fertilizer per mu, 15 to 25 kilograms of superphosphate and 10 to 20 kilograms of potash fertilizer as base fertilizer. There are two methods of spreading and strip application of base fertilizer. Strip application is applied by ridging and trenching before and after sowing. In addition, when sowing, 1000 kg of rotten dilute dung water or a small amount of nitrogen fertilizer is applied as seed fertilizer, which is beneficial to the whole seedling. Topdressing is mainly available nitrogen fertilizer, mainly applying jointing fertilizer and booting fertilizer. The best topdressing stage of sorghum is at jointing stage and big trumpet stage, which can promote panicle differentiation and reduce floret degeneration. When the topdressing of urea exceeds 15 kg per mu, it should be applied in stages. Sorghum topdressing before heavy after light, heavy application of jointing fertilizer (jointing stage), light application of booting fertilizer (booting stage), generally 5 to 8 kilograms of potash fertilizer per mu and 40 kilograms of ammonium bicarbonate when 2/3 leaves are fully developed. Ditch strip application, hole application or spreading, should be accompanied by deep ploughing or watering, in order to give full play to the fertilizer effect. In the later growth stage, proper extra-root topdressing should be applied, and potassium dihydrogen phosphate (0.1%) or urea (2%) could be sprayed at heading and early filling stage to promote early maturity and increase yield. In the production of sorghum, we must pay attention to balanced fertilization, especially the combined application of nitrogen and phosphorus, which can avoid the imbalance of nutrient supply and significantly improve the fertilizer efficiency. On the low-yield land, the soil is lack of nitrogen and phosphorus, and the single application of a kind of fertilizer often fails to play a good role because of the imbalance of nitrogen and phosphorus ratio, resulting in fertilizer waste and little effect on increasing production. According to the experimental study, the combined application of nitrogen and phosphorus as seed fertilizer can promote growth, grow faster at seedling stage, increase leaves, grow strongly, enhance plant metabolic function, improve plant absorptive capacity, significantly improve fertilizer efficiency, increase ear weight and increase yield by a large extent. can multiply the yield. Therefore, reasonable collocation and balanced fertilization in low-yield soil is an effective measure of economic fertilization.