Experts teach you tube wheat fields
Chen Xiyong, associate researcher, answered questions about wheat fertilizer management and pest control. The answers to these questions are as follows: 1. What should be managed in late spring wheat field? In mid-October, 2003, the medium-to-large rains in the Huanghuai wheat region generally fell to the point of heavy rain, which coincided with the sowing date of wheat. This affected the timely sowing and normal emergence of wheat to a large extent. Weak, showing little or no tillering before winter, poor root growth. In view of the reproductive characteristics of late wheat, the following points should be noted in the spring management: (1) Delay spring water. Due to late sowing of wheat sowing, the effective accumulated temperature is not enough, the seedlings are weak, so management must do everything possible to increase the temperature and promote growth. Especially in early spring season, if the soil moisture content is large, the ground temperature will be significantly reduced. Therefore, generally, late-seeding wheat fields do not have frozen water and late spring water is poured. In 2003, it was a warm winter climate with very little rainfall. However, due to the general good public opinion before the winter, the spring drought was not very serious. The first spring watering time generally has to wait until the temperature rises steadily to above 5°C. Most of the seedlings grow after the tillers and secondary roots are poured. (2) cut loose soil. After pouring the spring water, it is necessary to plan the loose soil in time so as to facilitate warming and protection. (3) supplement nitrogen and phosphorus fertilizer. Late-seeding wheat seedlings have small roots and weak ability to absorb nutrients. To promote its growth, some nitrogen and phosphorus fertilizers can be directly applied. The method is to mix urea with a 1% to 2% aqueous solution and spray 50 to 100 kg per mu, which can be sprayed. Apply multiple times, can also add 0.2% to 0.4% potassium dihydrogen phosphate mixed spray. Watering can also be applied. 2. How to manage the jointing period of wheat? The main sign of the jointing period of wheat is about 2 cm out of the ground. After entering the jointing stage, the wheat tiller rapidly differentiates into effective and ineffective polarization, which is the key period for determining the number of ears per mu of wheat, and also has a direct impact on the number of grains per ear and grain weight at the later stage. Under normal circumstances, jointing water is always poured, but it should be based on the seedlings to decide "early pouring", "in the cast" or "late cast." Top dressing should also be based on the conditions of the seedlings at the time and the top fertilizer application to determine the amount of fertilizer. The basis for measuring seedlings is mainly to see the degree of polarization of the tillers, the strength of the plants, and the color of the leaves. Different management measures should be taken for different situations: (1) If the plants are weak, the leaves are greenish yellow and green. Significant or obvious differences between the two polarizations appeared earlier, and the base leaves turned yellow. Both showed malnutrition. They should be watered early and top-dressed early. (2) If the wheat sprouts are true, the leaves are light green, medium ridged, the ventilation and light transmission are good, the polarization is obvious, there is a clear difference between the stem stalks and the non-edible stems, and it is a sign of good growth. In the wheat field, water-spraying joint fertilizer should be carried out after the section is pulled out about 2 cm from the ground. Top dressing should not be excessive. (3) The seedlings are dark green, do not fade during jointing, and the leaves are generous and are signs of Wang Miao. The seedlings were generally severely ridged, and both large and small pods grew vigorously. The polarization was not obvious, and the groups were covered with shackles, indicating that the previous fertilizer and water were excessive. At this point should be poured pour water, that is, when the obvious polarization occurs when watering and top dressing. At this time, the 2nd season has been fixed, and the 2 leaves have appeared or spread halfway. 3. How to prevent wheat midge? After the wintering of wheat midge, larvae usually begin to break in the jointing period of wheat in late March. After the break, the larvae are prepared in 3 to 10 cm soil layers. In mid-April, wheat began to phlegm at the booting stage, and the emergence of adults began to emerge at the heading stage of wheat in late April, and the emergence was completed at the beginning of May. On the day of adult emergence, mating and spawning occurs. After the larvae hatch, they begin to harm the wheat grains. After 15 to 18 days of maturity, they fall into the soil and get over the summer and winter. Wheat midge generally occurs in the piedmont plain high-yield areas in Hebei, Hebei provinces of Fujian, Xingtai and Shijiazhuang. However, in recent years, it has gradually extended northwards to parts of north of Baoding and Hengshui and Quzhou, especially for new insect areas. The farmers did not know, did not control for many years, resulting in the accumulation of insect resources, and some counties and cities had serious problems. Control methods: During the flood season, use 0.04% of insecticide powder or 4.5% of enemy powder or 4% of enemy horse powder per acre, optionally add 2 kg of powder pesticide and 20 kg of fine soil to form toxic soil. 50% pungent sulfur EC 100 ml of water, 1 kg, sprayed on 25 kilograms of fine soil mixed with poisonous soil, Shun Mai ridge application. Before and after the flowering period, if the adult insects reach the prevention and control index, 150 grams of dichlorvos EC can be used for 2 kilograms of water, and the morning is sprayed on 20 kilograms of wheat (prickly soil or fine soil). After spreading in the afternoon, the adults can be steamed to kill the adults. 40% can also be used. Omethoate EC or 4000 times liquid for enemies to spray control.