Corn

1. Nutritional characteristics

Maize can be divided into three main stages: seedling stage, ear stage and flower grain stage. From seedling stage to jointing stage, it belongs to vegetative growth stage, mainly root and leaf growth. The ear stage from jointing to heading is an important period of vegetative growth and reproductive growth. At this time, maize vegetative growth is vigorous and the male and female ear are differentiated, which determines the ear size of maize. The stage from male extraction to maturity, including flowering, silking, filling and maturation, belongs to the reproductive growth stage and plays an important role in grain number and grain weight.

2, need fertilizer characteristics

During the whole growth period of maize, the amount and proportion of nitrogen, phosphorus and potassium required vary according to different factors such as soil, climate, varieties and planting methods. Yield 600 ~ 700 kg per mu, need to apply nitrogen (N) 12 ~ 15 kg, phosphorus (P2O5) 3 ~ 5 kg, potassium (K2O) 4 ~ 5 kg.

From jointing to flowering stage is an important stage for the formation of fruit spikes, which absorbs the most nutrients and the fastest, and is a critical period for fertilizer. Nitrogen and phosphorus absorbed in this stage account for more than 50% of the total growth period, and potassium accounts for more than 70%.

Maize is very sensitive to zinc, zinc application can significantly improve the photosynthetic efficiency, promote plant health, enhance disease resistance, prevent bald tips and grain deficiency, promote the early maturation of maize, delay the aging of leaves and stems, increase ear length, ear thickness, grain number per ear, increase thousand grain weight, and increase the mu yield by 8 ~ 15%. (This paragraph is from the Chinese Academic journal network "The effect of zinc on increasing yield in corn formula fertilization")

3. Fertilization technology

Base fertilizer: It is recommended to apply strong high-nitrogen special formula fertilizer (28-6-6, 24-7-7), 40 ~ 50 kg per mu.

Topdressing: For areas with high yield requirements, it is recommended to apply 5 to 10 kg of urea before and after jointing (7 to 9 leaves) to achieve the cultivation goal of stout stalks. 10 to 15 days before the maize was to be harvested, applying 10 to 20 kg urea or 10 to 15 kg high nitrogen formula fertilizer could promote the differentiation of female ear and flower, and achieve the purpose of ear size, grain size and yield increase.

Strip or spread, strip should pay attention to the separation of fertilizer and seeds, at least 8 ~ 10 cm distance, to prevent burning seeds and seedlings; Spreading should be combined with ploughing into the soil.