First, confirm the sowing date

After seeding, the seedlings emerged quickly, homogeneously and completely. During the growth process, they can meet good climatic conditions in various periods, grow steadily, and have high and stable yields.

1. The main limiting factor of spring maize sowing date in spring maize is temperature. Generally, the soil surface temperature is 5-10cm, and the soil temperature is stable at 10-12°C or more. The soil moisture content is more than 60-70% of the field water capacity. period. In the range of appropriate sowing, late-ripening varieties should be properly sowed early, dry soil, sand, it is advisable; wet soil, clay should be late; land, sunny place should be early; depression, backyard should be late.

2, the summer and autumn corn should fight for early sowing to prevent bud buds, to avoid cold damage later, reduce various diseases.

3, interplanting corn should ensure that the symbiotic period with the previous crop can not be too long, to ensure that during the symbiotic period does not enter the spikelet differentiation period, after harvest does not affect the late sowing.

4. The suitable sowing date for spring maize in the middle and lower reaches of the Yangtze River is from late April to early May. The suitable sowing dates for other regions are flexible according to local conditions.

Second, high yield corn fertilizer management

Phosphate fertilizers are absorbed during the whole growth period of corn, and it is also at the peak of growth and development. The absorption of phosphorus in the later period reaches a peak, but the phosphorus absorption in the later period is still about 1/3. Corn top dressing is a supplement to the nutrients needed during the corn growing season and is a necessary guarantee for realizing the high quality and high yield of corn.

(1) The fertilizer requirement of corn (1) The absorption of nitrogen by corn is relatively stable, and the male silking stage reaches a peak, the absorption rate of the filling stage is slowed down, and nitrogen fertilizer is absorbed throughout the growing period. (2) Phosphate fertilizers were absorbed during the whole growth period of corn, which was also the peak in the growth and development of the most vigorous tasseling silking period. Phosphorus absorption in the later period decreased, but still accounted for about 1/3. (3) The absorption of potassium by maize was the most from jointing stage to booting stage, and the flowering stage reached the highest. Afterwards, the absorption of potassium was stopped. On the contrary, potassium decreased in vitro due to extravasation of potassium.

2. Time, quantity and method of topdressing of corn The time, method and quantity of topdressing, as well as the application of different types of fertilizers according to the conditions of the shortage of fertilizers are the main factors affecting the yield of corn. Therefore, in order to increase the unit yield of corn and achieve high yields, it is very important to grasp the best top dressing time and the amount and type of fertilizer. (1) Dressing time: Top dressing should be carried out around 10 leaves of corn, which can promote spikelet differentiation. It is advisable to top-dress 2 times, and if you are busy, you can also top-dress in early July. (2) Number of topdressing: It is decided according to the law of sucking fertilizer of corn, yield level, ground force foundation, base fertilizer and seed fertilizer application. High-yielding fields, good ground conditions, and a large amount of basal fertilizers should adopt the top-dressing method of lightly catching Miaofei, reclaiming panicle fertilizer and supplementing the recovery of grain fertilizer. The amount of seedling fertilizer accounted for about 30% of the total topdressing nitrogen, about 50% for panicle fertilizer, and about 20% for pellet fertilizer. The secondary cropping field, better soil fertility base, and larger amount of basal fertilization should adopt the secondary fertilizer application method of applying sufficient seedling fertilizer and reclaiming panicle fertilizer, about 4% of seedling fertilizer and about 30% of panicle fertilizer. Low-yield fields, poor fertility foundation, and a small amount of basal fertilizer use top-dressing Miaofei and light-recovery panicle-fertilizer. The Miaofei accounted for about 60%, and panicles accounted for about 40%. (3) Miao Fei: It is generally applied from the post-seedling to the jointing stage (30% leaf age index). The imminent extraction of young shoots and jointing fertilizers are once applied, which has the effect of promoting roots, strong seedlings, and promoting leaves and strong stalks, laying the foundation for many panicles and spikes. In addition to the application of quick-acting nitrogen fertilizers, the seedlings may also be applied with both phosphate and potash fertilizers, as well as applied organic fertilizers. (4) Jointing fertilizer: Jointing fertilizer can promote the enlargement of the middle and upper leaves, increase the photosynthetic area, extend the photosynthesis of the lower leaves, and lay a good foundation for root promotion, strong stalk growth and propagation. Top-dressing joint-fertilizer is dominated by nitrogen fertilizer, and 10-15 kilograms of urea ditches can be applied per acre or acupuncture points can be applied to avoid topdressing before heavy rain to prevent leaching by rainwater. For fields with insufficient phosphorus and potassium fertilizers in the soil, three-element compound fertilizer can also be added to topdressing, which amounts to 7.5-10 kilograms per mu. (5) Panicle Fertilizer: In the large bell-mouth stage, corn topdressing panicle fertilizer can not only meet the nutrient requirement of panicle differentiation, but also increase the photosynthetic productivity of the middle and upper leaves, so that the nutrients transferred into the ear are numerous, and the grains are full and full. Fertilizer applied mainly to available nitrogen fertilizer, topdressing urea 15-20 kg per acre is appropriate. (6)Grain fertilizer: Refers to the top-dressing fertilizer for corn after pumping males, and it is generally advisable to top-dress at the filling stage. After the tasselling of corn, it takes up about 40% of the total nitrogen and phosphorus from the soil. At the same time, about 80% of the grain yield is based on photosynthetic yields produced by later leaves. Therefore, a certain amount of fast-acting fertilizers should generally be applied in the later period to ensure adequate supply of inorganic nutrients, extend the leaf functional period, increase the photosynthetic efficiency, increase the accumulation of photosynthetic products, and promote graininess and grain weight so as to obtain high quality and high yield.

35k Spot Welding Machine

Product categories of 35K Spot Welding Machine, we are specialized manufacturers from China,Portable Ultrasonic Spot Equipment, 35K Mask Ultrasonic Spot Welding Machine suppliers/factory, wholesale high-quality machine of ultrasonic Spot welding R & D and manufacturing, we have the perfect after-sales service and technical support. Look forward to your cooperation!

35K Spot Welding Machine,Portable Ultrasonic Spot Equipment,Hand-Held Ultrasonic Spot Welding Machine,35K Mask Ultrasonic Spot Welding Machine

Wuxi DIZO Ultrasonic Technology Company , https://www.dizosonic.com