Key points of sowing and Seedling Protection techniques of Spring Maize

In view of the drought in spring maize production areas in our province, it is very important to make scientific use of effective soil moisture and actively do a good job in selecting and sowing improved varieties, fine soil preparation, timely sowing and so on. The main varieties in Yulin city are Denghai 9, Yudan 9 and Zhengdan 958, with Qinlong 14, Shendan 16, Jinnong 118 and Zhongdan 2. Actively demonstrate and promote Xianyu 335, Hounong 101 and Xingyu 998. In Weibei spring sowing area, Shendan 16, Yuyu 22 and Xingyu 998 were the main varieties, with Hudan No. 10, Hudan 2000 and Sanbei No. 6 to actively demonstrate and popularize Jinnong 118. In Hanzhong and Ankang City, Zhengyu 203, Yuyu 22, Sanbei 6, Linao 1, Zhongbei Hengliu and Lianyu 13 were the main varieties planted with Nongda 95, Denghai 11, Dongdan 60 and Bofeng 109; actively demonstrate and promote Jinnong 118, Qinlong 14, Shulong 18 and Jinsui 888. No. 4 Huanghe Anyu No. 9 is planted in the alpine mountain area. In Shangluo City, Denghai 11, Linao 1 and Yuyu 22 were the main varieties, with Nongda 108, Nongda 3138, Qinao 23, Shangyu 2, Zhengda 12 and Xingyu 998. It is forbidden to use Yuyu 22, Nongda 3138 and Zhengda 12 in the areas with heavy incidence of large spot disease. The main variety of silage corn was Yayu 8, which was planted with Shaanzi No. 1 and Nongda 108. Second, before fine soil preparation and sowing, on the basis of winter soil preparation, depending on soil fertility and soil moisture, ploughing, irrigation, fertilization, raking and other measures should be carried out again to achieve fine soil preparation. Corn is generally not suitable for continuous cropping, it is better to choose stubble such as wheat and beans. Third, sowing at the right time in this spring soil moisture is poor, to achieve timely early sowing, 5-10 cm soil layer temperature stable at 10-12 ℃ is appropriate, early sowing temperature is low, evaporation is small, soil moisture is good, conducive to seed water absorption and germination. In the areas with severe drought, it is necessary to wait for the rain to sow seeds. The best sowing time is in the middle of April, and the late sowing should be no later than the end of April. Fourth, the way of sowing corn should pay attention to cover the hole mouth with soil after sowing with some guns, so as to avoid bad seedling emergence due to running moisture and poor contact between seeds and soil. When the soil moisture is poor, dry and wet seeds should be planted, and the method of deep trenching and shallow covering soil sowing and suppression should be adopted, which is beneficial to seed germination and emergence. The application of chemical fertilizer should avoid "burning seeds" caused by contact with seeds, and pay attention to the appropriate amount of chemical fertilizer. Soaking corn coated seeds will reduce the effect, it is easy to cause embryo injury and affect germination and emergence, coated seeds, direct sowing effect is better. Fifth, the sowing depth is generally 4-6 cm. The field with poor soil moisture can be sown by "sitting on water" to preserve the seedlings. In a word, the soil moisture should be shallow and the difference should be deep. Sixth, timely release of corn seedlings after emergence should not only release seedlings in time, but also persist in putting "green" rather than "yellow". Generally, the seedlings should be released from 9 to 10:00 in the morning on a sunny day, and then sealed with soil after releasing the seedlings, so as not to burn the seedlings with plastic film. 7. Corn seed coating has a good effect on the control of underground pests, but the seedlings are easily bitten by pests after being unearthed. Soil treatment or spraying control should be carried out in areas with heavy insect pests to kill pests. Eighth, timely management of maize seedlings after sowing and emergence found that lack of seedlings, timely transplanting or replanting, and strive for the whole seedling. In the fifth or sixth leaf period, we should pay close attention to setting seedlings and pay attention to ploughing and weeding, so as to lay a good foundation for high yield.