Wheat Grain-Filling Stage Management Tips: Do These Things Well for a High Yield

May has arrived, and winter wheat in various regions across the country is successively entering the grain-filling stage. This period is a critical stage for wheat growth and also directly affects the level of yield. So, how should wheat be managed during the grain-filling stage? Do these things well for a high yield!

1. Water the grain-filling water at the right time

Generally, during the period from the milk-ripe stage to the dough-ripe stage, and before the period when dry hot winds frequently occur in normal years, water according to soil moisture conditions. When the relative soil moisture is below 60%, water should be applied promptly. Four principles should be followed: first, water little but frequently, and the amount of water each time should not be too large; second, watering is strictly prohibited in windy and rainy weather; third, stop watering half a month before maturity; fourth, strictly control irrigation for wheat fields with excessive nitrogen fertilizer application.

2. Topdress with nitrogen fertilizer

10 to 15 days after the wheat flowering stage, topdress with nitrogen fertilizer, combined with watering, applying 3—5 kg of urea per mu. After 7 days, another topdressing can be applied. Supplementing nitrogen fertilizer during this period prevents wheat from premature aging during the grain-filling stage, and vigorous growth can increase the grain-filling rate, prolong the grain-filling time, increase the thousand-grain weight, and thereby significantly increase yield. At the same time, supplementary nitrogen fertilizer can enhance the stress resistance of wheat.

3. Spray foliar fertilizer

During this period, foliar spraying of potassium dihydrogen phosphate is needed 1 to 2 times. Whether irrigated land or dry land, potassium dihydrogen phosphate can be sprayed from the heading stage to the middle of the grain-filling stage. The usual dosage is 200 grams per mu each time, mixed with 40 to 50 kg of water for foliar spraying. For strong-gluten wheat, wheat fields that are yellowing due to fertilizer deficiency, frost-damaged wheat fields, and hail-damaged wheat fields, an appropriate amount of urea can be mixed in for spraying. Use 1 kg of urea and 100 grams of potassium dihydrogen phosphate per mu, mixed with 40 to 50 kg of water, and spray on the leaves 2 to 3 times, with an interval of about 10 days between sprays. In the late growth stage of wheat, the root absorption capacity weakens. Foliar topdressing can prolong the functional period of wheat leaves, improve photosynthesis, prevent disease and resist lodging, and reduce the harm of dry hot winds.

4. Strictly prevent lodging

The wheat grain-filling stage is generally at the end of April and the beginning of May. Pay close attention to weather forecasts. If strong winds occur, immediately stop field irrigation. According to the weather forecast, before storms, measures such as digging ditches for drainage can be taken to reduce the risk of root lodging and stem lodging caused by excessive water content in the soil and plants. If lodging occurs later, manual support is strictly prohibited to prevent greater damage. After lodging, the stems generally grow upward from the most vigorous meristematic tissue, recover their upright position, and some stems turn upright again, so photosynthesis and transport functions are partially restored.

5. Pest and disease control

During the wheat grain-filling stage, various pests and diseases such as aphids, wheat blossom midges, powdery mildew, rust, and fusarium head blight are prone to occur.

1. Aphids

When the number of wheat ear aphids reaches 800 per 100 ears and the beneficial-to-harmful ratio (natural enemies: aphids) is lower than 1:150, choose pesticides such as pymetrozine, acetamiprid, imidacloprid, pirimicarb, matrine, and Verticillium lecanii for spray control. Where conditions permit, biological control by releasing Aphidius wasps, ladybugs, and others is encouraged. In areas where multiple pests and diseases occur together, suitable fungicides and insecticides can be scientifically mixed and applied comprehensively.

2. Wheat blossom midges

Before wheat heading, phoxim granules can be made into poisoned soil and evenly spread on the ground surface, followed by watering for control. After wheat heading and before flowering, pesticides such as phoxim, beta-cyhalothrin, and lambda-cyhalothrin·imidacloprid can be used for spray control.

3. Powdery mildew and rust

In the early stage of disease onset, when the diseased leaf rate of powdery mildew in the field reaches 10% or the diseased leaf rate of leaf rust reaches 5%, promptly organize control. Fungicides such as triadimefon, diniconazole, pyraclostrobin, and propiconazole can be selected.

4. Fusarium head blight

If there are more than 2 consecutive rainy days during the wheat flowering stage, the first application time should be advanced to the heading stage. Fungicides such as phenamacril, tebuconazole, thiram, thiophanate-methyl, and Bacillus subtilis can be selected. Use a sufficient dosage. If rain occurs within 3 to 6 hours after application, timely supplementary treatment should be carried out after the rain.

In addition, doing a good job of field weeding during the wheat grain-filling stage is also very important. Weeds should be pulled out by hand before they set seed, to reduce the amount of grass seeds left in the field and prevent them from spreading and causing disaster. In particular, grass-family weeds are more harmful, and attention should also be paid to controlling weeds at the edges of fields.