What are the key technical points for wheat field management this year
Once the Start of Spring solar term has passed, temperatures will gradually rise, and wheat in our province will successively enter the greening-up stage from south to north. After wheat greens up, spring management should be strengthened. How should it be managed?
According to statistics from the Provincial Meteorological Bureau, from October 1, 2016 to January 17, 2017, temperatures in the wheat-growing areas of our province were 0.5-2°C higher than usual. Therefore, this year in the central-southern Hebei wheat-growing areas, the signs of wheat overwintering were not obvious; it was basically overwintering while still green, with no dried leaf tips, and the main wheat fields had no freeze damage or dead seedlings.
According to field survey results compiled by the Provincial Department of Agriculture, this year's wheat seedlings are uniform and consistent in growth, with a reasonable population. In the central-southern Hebei wheat-growing areas, the number of stems per mu is between 750,000 and 900,000, and in the central-northern Hebei wheat-growing areas, the number of stems per mu is between 700,000 and 760,000. Individual development is relatively good; the wheat seedlings are at the 5-leaf 1-heart to 6-leaf stage, with 2-3 tillers per plant. First- and second-class seedlings account for 92% of the total wheat field area in the province.
However, this climate also brings many unfavorable factors to wheat growth and development. First, it increases the overwintering base of pests and diseases. Although there were several cold weather processes in winter, they were short in duration, and temperatures were generally high, so the overwintering base of pests and diseases is relatively large, and there will be a trend toward more severe occurrence. Second, diseases occur earlier. There were many foggy and hazy days in winter, and under the influence of low temperature and scant sunlight, root rot and stem rot occurred early in some wheat fields. Third, spring weeds may break out. Last year, wheat fields entered winter earlier, and most wheat fields did not have time to carry out autumn weed control before winter, resulting in a relatively high base of weeds in wheat fields, which puts pressure on spring weed control. Fourth, some wheat fields may show a trend toward excessive growth. For wheat fields sown early in autumn and with a large sowing rate, excessive growth may occur, increasing the difficulty of field management. Fifth, some plots have relatively serious soil moisture loss. Many plots did not form a frozen soil layer, and winter precipitation was low. As temperatures rise, soil moisture loss will accelerate. In addition, there are still many uncertain factors, such as whether adverse weather such as a "late spring cold" or drought will occur. In view of this, wheat field management this year cannot be relaxed. It is necessary to grasp every key link, prepare medicines and equipment early, pay attention to the development of pests and diseases, and strengthen management according to the field and the seedlings.
Doing a good job of pressing is the primary measure in spring field management. Pressing can firm the soil and fill cracks, especially with better results in wheat fields where straw has been returned to the field. Pressing can raise soil moisture, preserve soil moisture, and increase temperature, promoting wheat seedling greening-up. Pressing can control excessive growth and adjust the population structure. Pressing is usually done with a convex-concave roller. The pressing time should be early rather than late. Where conditions permit, mechanical hoeing and scratching can be adopted to achieve the effect of raising temperature and preserving soil moisture.
Doing a good job of pest and disease control is an important measure throughout spring management. Strengthen field monitoring. Once disease appears, treat spots as patches and patches as areas, control the center of infection, and strictly prevent large-scale spread. When controlling, use low-toxicity or biological pesticides, ensure sufficient spray liquid, spray thoroughly and penetrate well, and improve the control effect.
Skillful fertilization and watering are measures that cannot be ignored in reflecting green management. On the premise of meeting the nutrients needed for wheat seedling growth, use as little chemical fertilizer as possible, improve fertilizer use efficiency, and control chemical fertilizer use to zero growth. In irrigation, according to the water requirements of water-saving varieties, combine with topdressing, reduce the number of irrigations and the amount of water applied, and improve water use efficiency. To meet these requirements, formula fertilization should be adopted, the "integrated water and fertilizer" technology should be used, and the practice of "heavy fertilizer and heavy water" should be eliminated.
Adapting measures to local conditions is a flexible measure in field management. In field management, conventional practices should be broken, and flexible measures should be adopted. For example, after weather such as a "late spring cold" or "drought with little rain" occurs, corresponding rescue measures should be carried out in response, so as to achieve a great wheat harvest.