Suggestions on spring management of wheat field in central and southern Hebei

Recently, the author investigated the wheat overwintering in Longyao County and the surrounding area. generally speaking, affected by the warm winter, except for freezing damage in some weak seedling fields, the seedling condition of most wheat fields was normal. Although many wheat fields are not watered with winter water, there are several rains in early winter, coupled with more haze days, less windy weather and sufficient soil moisture. Therefore, the following suggestions are put forward for spring tube in wheat field:

1. Wheat fields with late sowing and high sowing rate (more than 20 kg / mu)

Because the wheat seedlings grow around 3-4 leaves before overwintering, the individual is weak, the tiller is thin or not, the accumulation of nutrients in the body is little, the cold resistance is decreased, the first snowfall in early winter, some have frost injury, and most fields show dry pointed yellow leaves. The following points should be done in spring management.

1. A wheat field with more dead seedlings after overwintering. After turning green, rake in time, get rid of dead leaves, watering when the temperature is more than 5 ℃, small water is suitable, 10 kg urea per mu of water should be applied, and after watering, when the soil moisture in the wheat field is suitable, hoe should be used to preserve soil moisture.

two。 Wheat fields where there are no dead seedlings or fewer dead seedlings after overwintering. Rake and hoe should be carried out in time after turning green, and those who are in danger of lodging can crush the wheat field or deep ploughing before Rain Water festival, and 15% paclobutrazol can be sprayed if there is still a growing trend after rolling and hoing.

2. Wheat fields with suitable sowing rate and early sowing

Generally speaking, there are more than 3.5 tillers per plant, and the number of stems per mu is more than 900000, even reaching 1.2 million. Many fields have been tightly covered by wheat seedlings, and this kind of wheat field accounts for the largest proportion this spring, which is a typical flourishing growth. The goal of spring management is to promote prosperity, prevent cold and fall, and prevent "late spring cold" in advance. The specific measures are as follows:

1. Repression. Restrain the over-rapid growth of the aboveground parts, avoid early jointing, and control prosperity and become strong. Suppression time in the temperature above 3 ℃, after turning green, noon to 5 pm before; tools can be used self-made steel pipe and cement pipe, generally along the ridge pressure, not too fast, 60 mu per day. Pay attention to no pressure in frozen wheat fields, saline-alkali land, weak seedlings and dry sand. Dry pressure on wet ground, no pressure on cloudy days, no pressure on sunny days, and no pressure on noon in the morning.

two。 Rake and hoe. It can not only increase the soil moisture, but also control the growth and promote strength. Raking the fields with many dead leaves and large groups in time can clear ridges, control growth and promote seedlings to become strong; small plots can be hoed, paying attention to shallow and fine hoes, generally 2 or 3 times from turning green to jointing, and wheat fields in danger of lodging must be ploughed deeply before and after getting up.

3. Apply growth regulators. For the fields that still have a trend of prosperity and growth after suppression and hoing, 15% paclobutrazol is used for 30 grams per mu, and foliar spraying of 25 kilograms of water is carried out, paying attention to no leakage and re-spraying. For those whose growth weakens after suppression and hoing, plant growth regulators such as potassium dihydrogen phosphate, Tianfengsu or Shuofeng 481 can be sprayed per mu to promote plant robust growth and improve stress resistance. Foliar fertilizer spraying can be combined with disease prevention and pest control.

4. Prevent the cold in late spring. After entering April, listen carefully to the weather forecast to prevent the cold in late spring. Before the cold spell comes, those with watering conditions should be watered, combined with watering to apply available nitrogen fertilizer. If there is no watering condition, foliar fertilizer spraying (water) should be carried out. After the occurrence of harm, the lighter, with green leaves, immediately carry out foliar fertilizer spraying; if the occurrence is more serious, if there are no green leaves, when the green leaves grow, plant growth regulators such as potassium dihydrogen phosphate, Tianfeng Su or Shuofeng 481 will be sprayed on the leaves.

3. Normal wheat fields with strong growth

It refers to the first class seedlings with more than 700000 tillers per mu and the second class seedlings with 600000 ~ 700000 tillers per mu. It is necessary to adhere to the "normal management" and the combination of promotion and control, so as to ensure the normal development of individual development and the appropriate development of population size. the number of stems per mu is 1 million ~ 1.2 million at jointing, so as to achieve more plants per panicle, larger spikes and more grains. The following measures can be taken:

1. For a class of seedlings. After turning green, rake and hoe can be carried out to increase soil moisture and preserve soil moisture, and then delay the return of green water. generally, the first water in spring is moved to the jointing stage of wheat, that is, at the end of March and the beginning of April, appropriate fertilization is applied when watering.

two。 For second-class seedlings. Similar to the first kind of seedlings, if the soil moisture can meet the green growth of wheat in spring, generally do not irrigate the green water, but only carry out hoing to preserve soil moisture, and the first water in spring is delayed to be irrigated when the temperature is higher, combined with watering, it can supplement an appropriate amount of nitrogen and phosphorus quick-acting fertilizer 10 kilograms.

IV. Wheat fields and desalted wheat fields in sandy soil areas

We can do a good job in suppressing and preserving soil moisture in advance, pay close attention to irrigation after the wheat turns green, and apply 5kg urea per mu to supplement nutrition, increase tillering in spring and increase the panicle rate of tillers.

The causes of abnormal seedlings such as "stiff seedling", "small old seedling" and "yellow seedling" should be analyzed, generally due to poor quality of straw returning to the field, poor quality of soil preparation, lack of soil moisture, or soil consolidation, poor air permeability, thin soil layer, poor fertility or shortage of phosphorus and potassium. When the temperature is high, the yellow seedlings caused by lack of soil moisture or lack of fertilizer should also be supplemented with fertilizer and water, because of their few tillers and secondary roots. coupled with low temperature and weak root activity, wheat weakens its ability to absorb fertilizer in the soil. 1% urea water + 0.3% potassium dihydrogen phosphate solution can be used to promote the transformation of seedling condition.

Huang Yongshan, Vocational Education Center of Longyao County