Rice

1. Nutritional characteristics

The vegetative growth stage of rice includes seedling stage and tillering stage. The goal of fertilization in this stage is to strengthen seedlings, promote tillering and ensure the number of ears per unit area. Reproductive growth includes booting stage, heading stage, flowering stage and maturity stage, and fertilization at this stage is to ensure large ears, more grains and increase grain weight. Panicle number per unit area, grain number per spike and 1000-grain weight are the components of rice yield.

2, need fertilizer characteristics

In the whole growth period of rice, the amount and proportion of nitrogen, phosphorus and potassium required vary with soil, climate, varieties and planting methods. The yield of 450 ~ 500 kg per mu requires the application of nitrogen (N) 8 ~ 12 kg, phosphorus (P2O5) 3 ~ 6 kg, potassium (K2O) 5 ~ 8 kg.

The growth period of single-cropping rice was long, and the absorption of N, P and K had two peak periods, namely the full tillering stage and the young ear differentiation stage. However, the growth period of early and late two-season rice is short, and the absorption of nitrogen, phosphorus and potassium forms a peak 2-3 weeks after transplantation, that is, the two absorption peaks tend to overlap, so the center of gravity of fertilization is earlier than that of single-season rice, and the fertilizer application amount is relatively small.

Rice is the crop that absorbs the most silicon. Application of silicon can enhance rice's resistance to pests and diseases and lodging resistance, improve plant type, increase light energy utilization rate, reduce leaf transpiration loss and increase water utilization rate. Generally, it can increase production by more than 10% and improve the quality of rice. Especially in the newly modified paddy field, cold soaked field and acid soil, the effect of applying silicon fertilizer to rice is more obvious. (This paragraph is excerpted from "What effect does silicon fertilizer have on Rice?")

Rice is very sensitive to zinc, can effectively increase plant height, increase the number of effective tillers, at the same time, the number of grains per spike and thousand grains weight are increased, reduce the blank rate, generally can increase more than 15%. (This paragraph is from the Journal of Plant Nutrition and Fertilizer, "Effects of different application methods and amounts of Zinc Fertilizer on the yield increase of Main grain crops in China")

3. Fertilization technology

Base fertilizer: It is recommended to apply high nitrogen and high potassium special formula fertilizer (22-6-12, 18-5-12), 40 ~ 50 kg per mu.

Topdressing: For areas with high yield requirements, it is recommended to apply tillering fertilizer 8 to 10 days after transplantation (early rice in single season, 5 to 7 days), and apply urea 10 to 20 kg per acre or special formula fertilizer with high nitrogen and high potassium 10 to 15 kg. 35 to 40 days after transplantation (15 to 20 days before heading), ear fertilizer, mu of urea 8 to 10 kg, potassium chloride 5 to 6 kg.

Scatter and spread the cultivated land into the soil.