Ministry of Agriculture: technical guidance for Huang-Huai-Hai summer corn to resist summer drought and protect autumn grain

Corn expert guidance Group of the Ministry of Agriculture

(30 July 2014)

Since June, there has been little precipitation in most of the Huang-Huai-Hai region, with a continuous high temperature in July, and the drought in some areas has developed rapidly. At present, Huang-Huai-Hai summer corn is in the stage of big trumpet mouth, and some of them enter the stage of male silking, which is the period of the largest water demand and the most sensitive period affected by water shortage. In view of the adverse effects of sustainable drought on the growth and development of summer maize, the Ministry of Agriculture organized experts to formulate technical guidance for Huang-Huai-Hai summer corn to resist summer drought and protect autumn grain. It is proposed that we should focus on "scientific drought resistance, classified guidance, simultaneous attack of fertilizer and water, disease prevention and pest control" to strengthen field management and minimize disaster losses.

(1) to open up a wide range of water sources for drought resistance so that they can be watered as much as possible. At present, Huang-Huai-Hai maize is in a critical period of female and male ear development, and the water demand of maize plants increases, and drought will not only reduce the number of effective filaments and grains, but also cause difficulties in heading, resulting in "sticking neck drought". It is necessary to overcome the fluke mentality of relying on the weather and waiting for rain, make full use of all drought-resistant water sources, open ditches to divert ditches, dig wells to carry water, speed up the progress of watering, expand the irrigation area, and strive to irrigate one ridge is one ridge and one mu is one mu. At the same time, according to the actual situation, sprinkler irrigation, furrow irrigation, sectional irrigation, small border irrigation, pipeline water transport, alternate furrow irrigation and other water-saving techniques are adopted to improve water use efficiency and reduce the adverse effects of high temperature and drought on maize.

(2) to do a good job in classified management according to the soil moisture policy of the seedlings. In the allocation of water resources, it is necessary to focus on the allocation of limited water sources to medium-and high-yield fields with good soil moisture conservation effect and great potential for increasing production. For the plots with different seedling conditions, the corn growing to the big trumpet stage should be irrigated first, and then the corn which has been scattered powder or before and after jointing should be irrigated. In the area of water shortage in hills and hills, the soil moisture can be preserved by hoeing, the evaporation of surface water can be reduced and the drought tolerance of corn can be prolonged. The corn which has been pollinated is assisted by artificial pollination to reduce the effect of high temperature on seed setting rate. For the areas that have not yet formed agricultural drought, we should make preparations for drought resistance as soon as possible, and replant and replant the seriously affected plots in time to make up for the disaster losses.

(3) attack both fertilizer and water to promote growth and development. For irrigated plots, shallow and middle ploughing should be adopted after irrigation, so as to cut off the capillaries on the surface of the soil and reduce water evaporation in the field. Where recent precipitation occurs, ear fertilizer should be applied in time, 15-20 kg of urea per mu to promote the rapid growth of corn. For the plots where the drought has not been relieved, foliar fertilizer, 1000-fold solution of potassium dihydrogen phosphate or 500-1000-fold solution of Handilong should be sprayed in time to reduce temperature and humidification and improve the ability of drought resistance of plants. For the plots where the growth period is delayed and the seedlings are weak, it is necessary to apply more urea to speed up the growth process.

(4) prevent and cure diseases and insects and reduce damage and losses. Wet disease, xerophytes. Continuous high temperature and drought can easily cause the occurrence of armyworm, aphid, corn borer and so on. Emergency prevention and control should be carried out in time according to the disease and pest information released by the plant protection department. If we scientifically grasp the timing and dosage of drug use, we can use the drug sooner or later, appropriately increase the frequency of drug application, reduce the drug concentration, and avoid drug damage. Choose pyrethroids, organophosphorus or insect growth regulators insecticide spray, or use phoxim, chlorpyrifos or Bt granules into the corn trumpet control. Where there are conditions, machine defense and flight defense operations should be adopted to improve the efficiency of prevention and control. Areas with sufficient Rain Water and good soil moisture should pay attention to the prevention and control of diseases such as dwarf disease, rough dwarf disease, leaf blight and so on.