I. Seedling Pest Control The main pests of corn seedlings include armyworm, cotton bollworm, spurts, thrips, and swans. For the control of armyworm and cotton bollworm, 5% beta-cypermethrin, 2.5% lambda-cyhalothrin 50-75 g/mu can be used, and 30 kg of water can be sprayed for prevention and control. The prevention and control of the Swedish fly must be controlled by spraying 50ml of 15% high-chlorinated chlorpyrifos at the beginning of the emergence of maize (ie, one leaf and one heart). If the affected plants are found in the field, the harmful insects should be removed in time to endanger the light ring strain. Cut the tip of the plant. Prevention and control of cultivating keratin meal can be done with 50% phoxim EC 500-1000 ml/mu and 48% Le Siben EC 200-400 ml/mu. Seedling disease control seedling disease mainly corn rough dwarf disease. The dwarf disease is transmitted by the planthopper, so it is necessary to do a good job in pest control and disease prevention. Prevention of virus diseases can be achieved by spraying insecticides on field side weeds before corn sowing or before emergence, spraying with imidacloprid, corn at the time of one leaf, using 20% ​​of virus A wettable powder 500 times plus 10% of imidacloprid 30g/ Mu spray, spray once every 7-10 days, even spray 2-3 times; In addition, it can also take agricultural control measures to remove diseased plants and retain strong strains when thinning seedlings. Weeds can be used to control the weeds that have grown up before the planting and have a large density. For example, weeds (paraquat) or glyphosate can be used to kill weeds; corn seedlings can be treated before planting. Mu with 40% Ethylene Mixture 200g and other watered 40-50kg spray; corn emergence to 7 leaf stage, weeds 2-5 leaf stage, mu 4% Nicosulfuron 90-100g, water 30- Spray 50 kg of stems and leaves, pay attention to post-emergence corn herbicides to ban organophosphorus pesticides 7 days before and after application to avoid phytotoxicity.