Sowing date selection is the basis for wheat to obtain high yield, suitable sowing date, and good temperature, water and fertilizer, can promote high yield and high quality, on the contrary, it is necessary to hinder the growth of plants.
In recent years, there has been a lot of debate about early sowing and late sowing, and late sowing has gradually become the mainstream view, and more and more people choose to promote the plant growth process through late sowing.
Although practical experience also shows that late sowing can indeed have a promoting effect, this promotion effect is limited, and improper planting management can also have a negative effect.
In order to select the appropriate wheat sowing date and improve the yield quality in an all-round way, it is necessary to clarify the shortcomings of sowing too early and too late, and master the technical scheme of late sowing.
Disadvantages of premature sowing date
The sowing time is too early, the temperature during the day is high, the wheat emerges quickly, grows vigorously, the plant grows vigorously, consumes excessive nutrients, and encounters frost damage in case of cooling.
The seedlings are growing too vigorously. The higher the temperature, the more abundant the water, the more nutrients are sufficient, the seeds absorb water quickly, the activity of enzymes is enhanced, and the wheat seeds germinate and germinate, which can be quickly unearthed.
In this state, the seedlings can obtain a good growth environment that far exceeds the actual demand, and the adverse effect is that the seedlings are too prosperous before winter, resulting in the problem of "winter is not prosperous in spring".
Reduced frost resistance. Wangchang wheat is characterized by tall plants, large leaf area, early tillering process, and the early use of nutrients is too fast, and there will be the problem of diseased yellow seedlings before winter.
In the deep winter, when the plant encounters a natural environment with strong wind and low temperature, the root system will be frostbitten and cannot overwinter, threatening the normal growth of the plant.
Pests and diseases and lodging problems. The exposure to pests and diseases is mainly concentrated in the winter, because the number of tillers in the early stage is large, and the field is gloomy and closed after returning to green, and the drainage is not smooth, which will cause diseases such as sheath and root rot, and will also provide a breeding ground for pests to grow.
As long as it is a vigorous wheat, whether it occurs before winter or after spring, it is inevitable that the problem of plant height and thin stems will be lodging in case of violent storms and rains, and the yield will be reduced and the quality will be reduced, and the harvest will be lost.
Disadvantages of late sowing
At present, as global temperatures rise, a moderate delay in the original planting date can be more beneficial to plant growth, but this does not mean that planting can be delayed indefinitely. Problems caused by late sowing:
First of all, the emergence of seedlings is uneven. Temperature is the basic condition for seed germination, above 24 °C, seed respiration is enhanced, germination is blocked, below 10 °C, germination speed is slow, and infection with diseases.
In the temperature environment of 15-20 °C, the higher the temperature, the faster the seed absorbs water, and the faster the germination and emergence.
The second is the problem of yellow disease seedlings. If the temperature is too low, the root extension and expansion ability of the plant is reduced, and the ability to obtain nutrients is reduced, and the plant is yellow and weak.
If the management measures of irrigation and top dressing are adopted, the absorption capacity of the plant is limited, and the growth can not be fully recovered, even after spring, the return to green is slow, the booting rate is low, and the problems of diseases and pests are very prominent.
Therefore, the sowing time is too late, the accumulated temperature of wheat before winter can not meet the demand, the plants are weak, and the number of tillers is small, which is not conducive to successful wintering, so choose carefully.
Late-seeding technical solutions
Through an appropriate amount of delayed sowing period, plant growth can be improved to a certain extent, and the yield and quality can be improved.
Seed selection and dressing. Selecting suitable and excellent wheat varieties is the basis for high yield, and grassroots producers should choose wheat varieties with high yield and late-sowing characteristics according to climatic characteristics and planting habits.
At the same time, it is also necessary to be able to use suitable agents for seed dressing treatment, avoid frost damage and germs and insect pests, stir evenly, make full contact with the pesticides and seeds, and then dry them for later use.
Increase the number of broadcasts. Compared with the normal sowing of wheat, the sowing date of late-sown wheat is late, and the temperature gradually decreases, in order to improve the poor emergence of seedlings, it is necessary to increase the amount of seeds appropriately, and the longer the extension of sowing, the greater the amount of seeds.
Moreover, it is necessary to take into account the amount of soil quality to adjust the amount of seeds, the water content of clayey soil is large, the cooling speed is fast, the greater the restriction on the growth of wheat seedlings, and the amount of seeds should be increased; On the contrary, if it is a sandy soil, the restriction is small, and the amount of seed used is not too large.
Adequate land preparation. Before sowing wheat, it is necessary to prepare the land in advance, and take measures such as deep ploughing, pressing harrow and hanging harrow, which can promote the circulation of water and fertilizer in cultivated land and store energy for plant growth.
As long as the soil is deeply ploughed and harrowed, the roots of late-sown wheat can be deeply rooted, and the deepest can be up to 1 meter deep, and the tillering amount, ear setting rate and lodging resistance performance can be greatly improved.
Scientific fertilization. For late-sown wheat, it is necessary to apply foot fertilizer in advance to increase soil fertility in the field and increase the stress resistance and cold resistance of wheat plants.
Fertilization should be able to combine organic fertilizer and chemical fertilizer, use the whole growth period of phosphate fertilizer as base fertilizer, reduce the amount of nitrogen fertilizer and potassium fertilizer, and then apply these two types of macro elements in the process of top dressing.
Sowing date selection. According to past experience, the late sowing time in the northern, central and southern parts of the Huang-Huai-Hai region is October 5-12 (not later than 15), October 7-15 (not later than 20) and October 15-20 (not later than October 30), respectively.
The late sowing time is only a reference, and the sowing time should be flexibly adjusted according to the actual local temperature changes and the selected wheat varieties.
Finally, the choice of sowing date will affect the yield and quality, but the extent is limited, if you want to increase the yield and improve the quality in an all-round way, it is necessary to have a deep grasp of pest management, water and fertilizer management and other field management matters.
Common management techniques include irrigation of overwintering water, suppression and control of prosperity in early spring, focusing on the prevention and control of scab, and strengthening the management of cold and dry and hot air in late spring, so as to achieve the goal of high yield.