1 Selection of Water-to-Fat Dry Maize Variety Selection of paddy-field corn varieties is the most important technical link to achieve high-yield harvest. Drought-reducing soil is more difficult to grow than ordinary dry land, poor permeability, low temperature and lack of beneficial microorganisms in dry field crops.
The first is not conducive to the seed germination and normal emergence of maize, often there are large areas of lack of seedlings broken and three types of seedlings, and ultimately lead to severe production cuts; Second, is not conducive to the growth and development of corn seedlings, adverse soil conditions often make corn physiological metabolism Misadjustment, uneven growth in the field (the so-called cloud seedlings), some species will also appear a lot of purple seedlings, yellow seedlings, slow growth, especially in the spring when the cold weather is more serious. Therefore, when paddy fields are replanted into dry fields, the varieties with low temperature tolerance, hard coleoptiles, strong arching ability, fast seedling growth, and well-developed root systems should be selected first;
The second is to select seeds with good seed maturity, no frostbite, high germination rate, strong bud potential, and to lay the foundation for the transformation of dry maize seedlings, seedlings, seedlings, and seedlings;
The third is to select suitable varieties for the growing season. Due to the low soil temperature and slow temperature rise in the paddy fields, the soil compaction is not conducive to the early development of maize and the growth period is prolonged. Special attention must be paid to the fact that varieties with long ripening periods cannot be selected. The longest period in Shenyang is not allowed. More than 130d.
The fourth is to choose varieties with good resistance, mature stems, premature aging and lodging resistance. The water content of paddy soil is high, and the seedlings cannot stand up in the early stage, which often causes the plants to be high. Avoid planting with easy lodging and premature aging varieties. When buying seeds, first look at whether the distribution seed unit has the approval number or official document for the variety, or do not buy it easily. Fully consider the local cultivation level and input level, according to the local land with different fertility, and different fertilization levels, select varieties that adapt to the local ecological conditions, and conduct reasonable planting. For exotic breeds, choose carefully, blind introduction may bring loss to production.
According to the current grain purchase characteristics and market demand, the selected varieties of grains must have good commercial properties, high keratin content, high bulk density, and rapid dehydration of the seeds during harvest, which is conducive to sales and storage.
2 Problems to be Solved in the Cultivation and Management of Water-to-Fertilized Dry Maize The management of drought-tolerant corn plantation, density, fertilization, and pest control can all be conducted with reference to the technical requirements for dryland corn production. However, the following aspects need special attention:
2.1 Fine soil preparation In order to overcome the shortcomings of paddy soil, it is necessary to finely soil preparation, loose soil, increase soil temperature and ventilation, and create good soil conditions for seed germination and seedling growth. Ensure that the field emergence rate is high, Miao Qi, Miaozuo, Miao uniform, Miao Zhuang.
2.2 Increased farmyard fertilization Due to the long-term use of chemical fertilizers in paddy fields, the loss of soil moisture and nutrients is serious. Soil compaction, soil organic matter reduction, and soil desaturation are serious. Reapplying farm organic fertilizer, combined with phosphate fertilizer and a small amount of nitrogen fertilizer as base fertilizer, can improve the soil structure, which is conducive to soil and water conservation and the absorption of nutrients by maize.
2.3 Seed selection and coating purchased seeds, remove the bad grains and pods, drying before sowing, select the appropriate seed coating agent to coat the seeds, so as to enhance the field emergence rate can also control underground pests, mice and diseases .
2.4 Timely sowing of paddy field soil surface temperature is relatively slow, so the sowing can not be too early, in Shenyang, generally from April 20 to May 1 sowing is more appropriate.
3 Drainage and flood control corn is good for fertilizer but not resistant to waterlogging. Excessive moisture during the growth of corn can cause damage. When the water capacity in the field exceeds 80%, it should be drained in time. The conversion of paddy fields into dry fields is generally relatively low, and more attention should be paid to preventing the occurrence of damage. The emergence of corn to seven leaves susceptible to damage. When the soil is too watery or stagnant, the roots will suffer damage and even death. When the soil moisture accounts for 90% of the field water capacity, it will cause seedling damage. The water holding capacity in the field lasted for more than 90% for 3 days. The maize leaf stage showed redness, thinness, and thinness, and the growth stopped. More than 5 days of continuous rainfall is weak yellow or death. In the middle and late stages of corn, the waterlogging resistance is strong. The depth of surface flooding is 10cm. As long as the blades are exposed to the water for 3 days, they will not die, but the yield is greatly affected. Before the 8-leaf stage, the ground was not exposed due to the growth point. At this time, the harvest was the most serious and even had no yield. If there is more than 10 days of continuous rain, the photosynthesis of the corn is weakened, and the plants are often thin and weak. After the big pod period, the tolerance of corn increased gradually. However, the rainfall during the rainy season from late July to mid-August was greater than 200 mm or the rainfall in early August was greater than 100 mm, which affected the normal flowering and pollination of maize, resulting in large amounts of baldness. And empty grains.