Technical guidelines for spring plowing and spring sowing of northern corn in 2021
By: Date: 2021-04-16 Categories: foodtechnology Tags: ,
   Maize Expert Steering Group of the Ministry of Agriculture and Rural Affairs
  National Agricultural Technology Extension Service Center
   At present, the northern spring corn is in a critical period of spring plowing and sowing. On the whole, the soil moisture in the northern region is relatively good, and the temperature rises quickly in spring, which is conducive to the realization of sufficient moisture sowing and one seedling. However, in some areas, the soil is wet, there are more windy weather in recent days, and the climate is uncertain, which will adversely affect corn planting and seedling emergence. In view of this year’s corn production situation and the characteristics of the northern climate, we will focus on improving the “three degrees” (corn seeding density, seedling uniformity and maturity), and focus on improving the quality of land preparation and seeding. We will fully implement the return of straw to the field, single-grain precision seeding, Key measures such as simultaneous sowing of seed and fertilizer and reasonable close planting have made every effort to lay the foundation for a bumper corn harvest throughout the year.
   One is straw treatment. According to local conditions, straw treatment methods such as corn stalk mulching and no-tillage, mulching strip tillage, deep ploughing and burying and returning to the field shall be adopted to improve the quality of returning straw to the field, improve soil fertility, store water and preserve moisture. Corresponding to the straw leaving the field but not leaving the field, speed up the progress of the straw leaving the field.
   The second is soil preparation due to soil moisture. For land preparation in autumn, deep turning of straw and returning to fields, we insist on keeping the bottom moisture content and sealing the surface moisture content. When the soil layer is thawed to 7-8 cm, it will be topped and sealed, and when it reaches 15-18 cm, it will be raked, ridged, and suppressed for continuous operation. For land preparation and ridging plots in autumn, when the soil layer thaws 3-5 cm, it will be suppressed. For plots suitable for spring soil preparation and soil moisture conditions, deep loosening, raking, drowning, ridging, and suppressing continuous operations when the soil layer thaws 10-15 cm. For arid plots, try to move the soil as little as possible, and adopt less tillage or no tillage methods for stubble sowing or original ridge seeding. For soil over-wet plots, timely mechanize snow to disperse moisture, and clear water plots are drained in time.
   The third is to choose improved species. According to the natural ecology and production conditions, select the national or provincial-level approved corn varieties that are suitable for maturity, high yield and stable yield, density and lodging resistance, adversity resistance and wide adaptation, disease resistance and insect resistance, and suitable for mechanized operation. Avoid planting varieties with a long growth period, and eliminate cross-region planting. According to market demand, select high-quality special-purpose or both grain and feed silage corn varieties according to local conditions.
  Fourth is a timely broadcast. Determine the best sowing date according to temperature, soil moisture, variety characteristics, cultivation methods, management level, etc. In areas where soil moisture is suitable, flat cropping and ridge cropping shall be adopted, and single-grain seeding shall be strengthened mechanically, and soil moisture shall be robbed for sowing. For plots with poor soil moisture or drought conditions and without water irrigating conditions, adopt no-tillage planting or flat planting, ditch planting, etc., and appropriate deep planting or deep covering of soil to increase the suppression; for plots with water irrigating conditions, adopt Technologies such as drip irrigation under mulch and shallow buried drip irrigation. For areas with severe drought conditions, it is advisable to”seed in water” or sow after watering to create moisture. For plots with high soil moisture and low ground temperature, ridges should be raised early to disperse moisture, increase the ground temperature, sow on the ridges, appropriate shallow sowing or shallow soil, and moderately suppress the next day. If the sowing conditions are not reached during the suitable sowing period, change to early-maturing varieties in time and increase the planting density appropriately.
  Five is reasonable dense planting. According to the variety characteristics, soil fertility, management level, etc., determine the appropriate planting density and construct a reasonable group structure. Generally, about 4000 seedlings per mu are protected. The land preparation and planting quality is high, the fertilizer and water supply is sufficient, the production conditions are good as a whole, and the density-tolerant and lodging-resistant corn varieties are used, and the seedling density per mu can be increased to 4500-5000 plants.
   Sixth is pest control. Experts predict that this year, corn leaf spot disease will occur more severely in some parts of the northeast; corn borer will occur moderately in most parts of the northeast; armyworm will occur moderately in most areas. Disease-resistant and insect-resistant varieties should be adopted, seed coating should be strengthened,”white seeds” should be prevented from falling into the ground, disease and insect pest monitoring and early warning should be strengthened, green prevention and control and biological prevention and control should be actively carried out, and high ground clearance spraying machines or plant protection unmanned can be used if conditions permit The machine conducts unified prevention and control, improves the prevention and control effect, and reduces the loss of pests and diseases.