How to manage late-sown summer corn? Keep these key points in mind

In recent years, due to factors such as late harvest of the previous crop, drought during the sowing period, and poor quality of rushed sowing, corn emergence has been poor, uneven, and the growth has been weak. As the saying goes: “summer fights for time, autumn fights for a moment.” Strengthening field management of corn, promoting plant growth, and ensuring that late sowing does not reduce yield are very important. In management, the focus should be on early and promoting, and the following points should be done well:

1. Irrigate early when dry. Irrigate the four key waters early: seedling-promoting water, jointing water, booting water, and grain-filling water. According to soil moisture conditions, the four irrigations should be done 5-7 days earlier than for normally sown corn to meet the water needs of each growth stage and promote rapid plant growth.

2. Apply fertilizer early. Apply stalk-promoting fertilizer, ear-promoting fertilizer, and grain-promoting fertilizer early, and supplement foliar fertilizer well. For late-sown corn, because sowing is later and the growth period is delayed, topdressing should be applied 5-7 days earlier to promote growth. At the same time, combined with fertilization, use 0.3%-0.4% potassium dihydrogen phosphate aqueous solution or 0.2%-0.3% urea aqueous solution per 667 sq m; use 1:1 biogas slurry for foliar fertilizer supplementation to promote nutrient transport and increase grain weight. Spray once every 7-10 days, for 2-3 consecutive sprays.

3. Thin seedlings, finalize seedlings, and check for and fill gaps early. After corn emerges, check for gaps and fill them in time. If missing seedlings are found, replant them as early as possible. Thinning can be done earlier, before the 3-leaf stage, and final seedling spacing can be set earlier, before the 5-leaf stage, to reduce nutrient consumption and resolve the conflict of too many seedlings competing for fertilizer and water.

4. Prevent and control pests and diseases early. The main diseases of corn include rough dwarf disease, smut, and stalk rot; the main insect pests include corn borer, armyworm, wireworm, and cutworm. They should be discovered early and controlled early to reduce diseased and insect-infested plants in the field and increase the number of healthy vigorous plants.

5. Reasonably increase density. Because late-sown corn misses the optimal sowing period, yield will be affected. Yield can be increased by appropriately increasing the density of retained seedlings. Generally, increase the number of plants by 10-15% per 667 sq m.

6. Harvest late at the proper time. On the premise of not affecting sowing of the next crop, harvesting appropriately later has a certain effect on improving corn yield and quality, or harvest with stalks to promote physiological after-ripening of the grains and achieve a yield-increasing effect.