It is crucial to sow spring corn with high yield.

Improving the sowing quality of spring sowing corn and actively doing a good job of selecting and sowing improved varieties, fine soil preparation and timely sowing are very important for preserving the whole seedling and winning a bumper harvest of spring sowing corn. 1. Select suitable varieties according to local conditions, and select middle and late maturing varieties with a growth period of 120 to 130 days according to heat resources and production practice. Through the comparative tests of varieties in recent years, the main spring maize varieties with outstanding comprehensive characters are Nongda 108 and so on. Second, due to the long growth period, spring corn should grasp the principle of applying more base fertilizer, and organic fertilizer should be applied early, combined with soil preparation, generally applying 2000 kg of organic fertilizer per mu. At the same time, with the application of chemical fertilizer, 30% of the total nitrogen fertilizer can be applied as base fertilizer, and phosphorus and potassium fertilizer can be used as seed fertilizer at one time during sowing, generally applying 15 kg of diammonium phosphate, 10 kg of potassium sulfate and 1.5 kg of zinc sulfate per mu. Third, improve the quality of sowing. Fine ground preparation. Spring corn requires deep ploughing, and autumn ploughing as early as possible. Timely stubble ploughing after the previous crop harvest is beneficial to soil ripening, water storage and soil moisture conservation, and elimination of diseases, insects, weeds and so on. The soil moisture must be preserved by raking after ploughing. Raking should also be carried out in late autumn and early spring to conserve soil moisture. In places with serious spring drought, continuous operation of pressing, raking and harrowing is used to make the soil compacted and more conducive to soil moisture conservation. It can be sown directly where the soil moisture is good, and replenish the soil moisture to sow seeds where the soil moisture is insufficient. two。 Seed selection and treatment. When buying seeds, it is best to choose coated seeds. For the uncoated seeds, seed selection, seed drying and chemical seed dressing should be done before sowing, so as to achieve the goal of neat, uniform, fast and early emergence. Seed selection is used to sow large and small seeds in order to improve the uniformity of seeds at seedling stage, and seed drying can improve seed germination energy and germination rate, usually 2-3 days before sowing. Chemical seed dressing can effectively control the occurrence of diseases and insect pests. 50% phoxim EC and 1.0 kg water can be used to mix evenly, spray evenly on 20-30 kg seeds and spread out for 3-4 hours. Sowing after drying in the shade can effectively control underground pests. Seed dressing with 25% rust rather wettable powder according to 0.3%-0.5% of seed amount, or seed dressing with 12.5% Subali wettable powder at 0.4%-0.5% of seed amount, can effectively prevent the occurrence of diseases such as maize tumor smut. Fourth, sowing spring corn at the right time is easy to cause low temperature rotten seed and uneven seedling emergence, and too late sowing will lead to the grain can not mature normally in the later stage. Sowing can be carried out when the soil surface temperature is 5-10 cm deep and the soil temperature is 10 ℃-12 ℃. The suitable sowing time in Hebei Province is generally from late April to early May, generally early in the south and late in the north, early in the plain and late in the mountains. Fifth, reasonable close planting and increasing planting density is an important factor to achieve high yield of spring corn. The planting density of the plots with higher soil fertility is generally more than 4000 plants, and the suitable planting density of the plots with lower soil fertility is 3500 to 4000 plants per mu, and the sowing rate per mu is 22.5 kg. The planting method should be equal row spacing or wide and narrow rows, and the sowing depth should be 4-6 cm. Chemical weeding technology chemical weeding not only saves time and effort, but also has a good effect, but we must choose safe and reliable corn field special herbicides and master its correct application method. Generally, chemical herbicides used in spring corn fields can be treated with soil treatment agents such as Yi A mixture. The dosage of Yi A mixture is 150,200ml per mu, and the water is 50kg. The soil can be closed before seedling after sowing. For the plots with poor soil closure effect, when the weeds grow in the 3-leaf and 5-leaf stage of corn and 2-4-leaf stage of weeds, the dosage of 4% Yunongle suspending agent is 100ml per mu and the amount of water is 30kg / mu to kill weeds. When spraying chemical herbicides, you should pay attention to using the medicine in the morning or evening when there is no wind and the relative humidity is more than 65%, and try to keep the sprinkler as low as possible so that the dosage is accurate, the amount of water is sufficient, and it is sprayed evenly, so as to avoid re-spraying and leakage spraying.