Technical guidance on Field Management of Huang-Huai-Hai Summer Maize in the later stage

This year, the sowing date of summer corn in Huang-Huai-Hai area is 3-5 days earlier than usual, the population uniformity is better, and the overall growth is better than the normal level. However, affected by the heavy occurrence of El Nino, the temporal and spatial distribution of rainfall was uneven, drought and waterlogging occurred in some areas, and the overall growth process was delayed. At present, most of Huang-Huai-Hai summer corn is in the grain filling stage, which is the key period of yield formation. In view of the recent sustainable development of drought, the Ministry of Agriculture organized relevant experts to hold consultations and put forward technical measures for field management to strengthen management, combat drought and disaster reduction, and strive to reclaim a bumper harvest of corn.

First, actively irrigate and arrange, protect ears and increase grains. When the soil water content is less than 60%, irrigate timely according to soil moisture and seedling conditions to meet the water demand of corn during the filling period and avoid the formation of "sticking neck drought". There is a high probability of rainfall in the middle and later stage of maize growth, so it is necessary to prevent the sharp turn of drought and flood, dredge the drainage ditch in advance, eliminate stagnant water in the field in time, reduce the water level and soil water content in the field, prevent waterlogging and lodging, and reduce the occurrence of stem rot. Ensure the normal development of maize female and male ears and the smooth progress of grain filling in the later stage.

Second, scientific fertilization promotes grain weight gain. This year, due to the heavy rainfall in the early stage, the loss of fertilizer utilization is heavy. The plots with signs of de-fertilizing should be fertilized scientifically according to the plant growth, and try to apply urea between rows of corn to prevent burning seedlings. In order to promote dry matter accumulation and increase grain weight, quick-acting nitrogen fertilizer should be applied as early as possible for the plots where the leaves turn yellow and the roots absorb weakly, and the mixture of urea and potassium dihydrogen phosphate should be sprayed on the leaves.

Third, disease prevention and pest control to reduce harm. Diseases and insect pests are easy to occur and difficult to control in the later stage of maize growth, so it is necessary to spray insecticides and fungicides in the middle and later growth stage to reduce the incidence of ear diseases and insect pests and reduce diseases. It is necessary to strengthen the monitoring of diseases and insect pests and carry out unified prevention and control and mass prevention and control in a timely manner. Focus on the control of corn borer, cotton bollworm, peach borer, armyworm, red spiders, aphids and other pests and leaf spot, stem rot and other diseases.

Fourth, timely and late harvest to increase grain weight. We will continue to vigorously publicize and popularize the technology of late harvest and yield increase of corn, and delay the harvest of corn to early October as far as possible, when the black layer at the base of the grain appears and the milk line basically disappears, that is, it can be harvested after physiological maturity, so as to maximize the full grain filling and maturity of corn and increase the yield. According to the characteristics of varieties and late drying conditions, mechanical rod picking and grain harvesting were popularized to realize the integration of mechanical harvesting and stubble control.

Fifth, promote deep ploughing and straw returning to the field. Deep ploughing fine rake, not afraid of drought and flood. Combined with wheat soil preparation before sowing, we should actively promote the techniques of deep ploughing and straw returning. Use a large straw grinder to turn the straw fine and deep in time, apply nitrogen fertilizer to speed up the rot; use a heavy disc Harrow to further cut up the straw and stubble, turn deeply and cover in time after the rake, so that the straw, fertilizer and soil are fully mixed, effectively improve the soil structure, improve the soil water seepage, water storage, fertilizer conservation and fertilizer supply capacity, and lay the foundation for the annual continuous yield increase of wheat and corn.