Management measures for early spring planting of spring maize in Liaoning

(1) Production preparation work before spring sowing

1. Select varieties that are suitable for maturity and excellent resistance. In the main producing areas of western Liaoning, Liaobei and central Liaoning, the varieties with the growth period of 125-132 days are selected; the original planting varieties in Liaodong area are basically middle-maturing varieties, and the original selected varieties are continued to be used; In the period, try to choose very late varieties.

2. Purchase high-quality fertilizers and pesticides to prevent and control pests and diseases. It is recommended to buy compound or mono-fertilizers produced by qualified large manufacturers, and purchase a sufficient amount of fertilizer according to the nutrient content of the fertilizer and the different fertility plots. Low-yield land: N fertilizer 10 ~ 12 kg / mu (equivalent to 22 ~ 26 kg of urea), P fertilizer 3 ~ 4 kg / mu (equivalent to 6.5 ~ 9 kg of diammonium phosphate), K fertilizer 3 ~ 3.5 kg / mu (equivalent Potassium chloride 5 ~ 6 kg); medium yield plot: N fertilizer 12 ~ 14 kg / mu (equivalent to urea 26 ~ 30 kg), P fertilizer 4 ~ 5 kg / mu (equivalent to 9 ~ 11 kg of diammonium phosphate), K fertilizer 3.5 ~ 4.5 kg / mu (equivalent to 6 ~ 7.5 kg of potassium chloride); high-yield land: N fertilizer 14 ~ 16 kg / mu (equivalent to urea 30 ~ 35 kg), P fertilizer 5 ~ 5.5 kg / mu (equivalent Diammonium phosphate 11 ~ 12 kg), K fertilizer 4.5 ~ 5.0 kg / mu (equivalent to 7.5 ~ 8.5 kg of potassium chloride).

Seeds must be coated before sowing. The seed coating agent to be used must contain underground pests (carbocarb, butyl thiocarbazone, imidacloprid, beta-cypermethrin, chlorpyrifos, cypermethrin, cypermethrin, methylisophosphorus, phoxim). And a mixture of two or more kinds of seedling diseases (Fumeishuang, Captan, Carbendazim, Froxonitrile, Jingjialing, Triadimefon).

3. Deeply leveling the land and keeping the work. In the spring, the whole site is based on “early”. From late March to early April, in the ground that has been removed from the roots, deep and land preparation, combined with the deep application of the base fertilizer, the depth of fertilization reaches 10 cm or more, with the ridge and the suppression, to be treated Broadcast status. The quality of the land preparation has reached no ploughing, no standing, no sloping.

(2) Timely increase, rush to sow

Strive to do a good seedling to protect seedlings. When 5 to 10 cm of plough layer, the ground temperature is stable through 10 C °, the soil water content can be sown when appropriate, generally suitable for planting from April 20 to May 10.

Sowing should be done: the seeds should be selected uniformly, and the seeds should be sun-dried for 2 to 3 days before sowing. Seed coating should be carried out before sowing; the sowing should be uniform to prevent leakage, and the depth of covering soil is generally 5~7 cm. Some, timely suppression after sowing, timely spraying chemical herbicides in 5 to 7 days after sowing to close the surface of the grass.

(3) Fertilization management

1. Take both organic fertilizer and chemical fertilizer, and apply the base fertilizer before and after the fertilizer. Combine the autumn soil preparation or spring land preparation with the base fertilizer, and apply the seed fertilizer (diammonium phosphate) when planting.

2. Phosphorus and potassium fertilizers are applied before sowing, and the total amount of nitrogen fertilizer is controlled. 30% to 40% of nitrogen fertilizer is applied before sowing.

3. Replenish the trace elements in the application. According to the soil nutrient and crop growth, determine the micro-nutrient fertilizer in the supplementary application, generally apply zinc fertilizer and boron fertilizer, with the application of base fertilizer or foliar application, the base fertilizer is generally applied 1.9 kg of zinc sulfate heptahydrate, borax 0.47 ~ 1 kg.

(4) Management at the seedling stage and the middle and late stages

1. Check the seedlings in time. Found dead seedlings, should be timely wet seed germination to replant, 4 to 5 leaves fixed seedlings.

2. Control pests and diseases. In the seedling stage, it is necessary to prevent the size of the spot disease, that is, spray the drug twice. The agents for controlling corn size spot disease include carbendazim, methyl thiophanate, Dasheng M-45, and mancozeb.