Cultivation techniques of upland rice in south and north in spring

I. Management techniques in the early stage of early rice production in South China.

At present, early rice should be planted before and after the Qingming Festival in the southern region, before and after Grain Rain in the central region, and before May Day in the northern region. Focus on the following technical measures:

The main results are as follows: 1. Cut into the seedlings with sufficient basal fertilizer and apply tillering fertilizer early. On the basis of applying good marriage fertilizer to the seedling field, 30 kg of calcium, 7.5 kg of potassium chloride and 25 kg of ammonium bicarbonate should be applied per mu of base fertilizer, and 1000 kg to 1500 kg of high-quality farm manure should be applied per mu where possible. There are 21000 ~ 25000 holes per mu, double seedlings per hole (two grains) for hybrid rice and 46.6 seedlings per hole for conventional rice. 5-7 days after planting, 5-6 kg of urea per mu was applied as tiller-promoting fertilizer, and 12-15 days after planting, about 7.5 kg of urea, 7.5-10 kg of potassium chloride, or 12.5-15 kg of compound fertilizer were applied as strong tiller fertilizer.

2. Transplant rice seedlings in thin water and turn green in shallow water. Keep 1.5 cm thin water in the field during transplanting and 3 cm irrigation in the field after transplanting. For the field of throwing seedlings, the water layer should not be left in the field when throwing seedlings, and the shallow water layer of 1.5 cm should be reirrigated after the seedling is set up. After turning green, enter the tillering stage, the field water layer should be kept below 2 cm. 15-20 days after planting (throwing), the tiller seedlings in the field began to drain and expose the field when they reached 200000 seedlings per mu.

3. prevention and control of diseases and insect pests. We will actively do a good job in the integrated control of rice blast (leaf blast), rice sheath blight, Chilo suppressalis, Chilo suppressalis and other diseases and insect pests.

2. management techniques at seedling stage of double-cropping early rice in the middle reaches of the Yangtze River.

In the first and middle of March, the area was dominated by overcast and rainy weather, and the sowing time of early rice was delayed, but due to the high temperature after sowing, the seedlings emerged quickly and grew healthily. If the weather remains fine in the later period, the early rice will be transplanted normally in mid-late April.

The following technical measures should be taken during the seedling stage of early rice:

1. Pay attention to irrigation of seedling field. After the weather turns fine at a low temperature, the seedling field should be sprinkled or irrigated in time, especially in dry raising seedlings to prevent green and dead seedlings.

2. Timely ventilation and seedling refinement. When the temperature rises steadily, it is necessary to uncover the thin film ventilation seedlings at both ends of the seedling box in time, especially in the case of high temperature weather, and water or irrigate the seedlings in time.

3. Apply seedling fertilizer scientifically. After removing the plastic film, evenly apply seedling fertilizer before and after irrigation or watering, generally applying 3-4 kg urea per mu of seedling field and 4-5 kg urea per mu of seedling field 3-5 days before transplanting.

3. Management techniques of raising seedlings of single cropping rice in southwest rice region.

At present, the temperature is suitable, the water source is abundant, the meteorological condition is better than all the year round, and the seed market is sufficient, which is beneficial to the management of rice seedling raising. However, in July this year, the sowing date of some farmers was 2-3 days later than usual; the quality of seeds used for production this year was not as good as that of normal years; the emergence of seedlings in some places was irregular, and the seedling rate of seedling formation decreased; seed soaking with dry seedling-raising agents was not fully implemented, and the infection of "evil seedling disease" in seedling beds became more serious; in addition, some farmers relaxed the management of seedling beds and reduced the quality of seedlings.

The following technical measures should be taken at present:

1. Arrange the sowing time and planting time scientifically. Winter fallow fields and green manure fields should sow seeds on time, seize the favorable weather and transplant in time, and actively popularize the enhanced cultivation techniques of super-high yield of rice if possible. In the wheat (oil)-rice double cropping area, the seedling age of conventional water-raised seedlings is shorter than that of dry-raised seedlings, the raising period of mechanical transplanting seedlings is generally less than 25 days, and that of plate raising and throwing seedlings is not more than 40 days. In the areas where seedlings are planted in rain all the year round, according to the technical requirements of cultivating "long-aged and strong tillers in dry land", effective technical approaches such as reducing sowing rate and spraying paclobutrazol should be adopted to increase the elasticity of seedling age.

2. Do a good job of seed treatment before sowing. It mainly includes the technical links of seed drying, seed selection, seed soaking and germination acceleration, in order to improve the germination energy and uniformity of seeds, prevent seedbed diseases, and sow enough seeds.

3. Check the seed germination rate and seedling emergence rate in time. In the areas where seedlings are about to be raised, the sowing amount should be determined according to the germination rate of seeds. If the germination rate is less than 80%, the sowing amount can be increased; in the areas where seedlings have already been raised, the number of mature seedlings should be evaluated. If the number of seedlings per mu of Honda seedlings is about 80% of the planned number, the management of seedling bed can be strengthened and strong seedlings can be cultivated to replace seedlings with tillers. If it is lower than 80% of the planned, it should be replanted in time.

4. Be on guard against seedling burning at high temperature and cold injury at low temperature. The key point is to strengthen the management of thin film and the regulation of water and fertilizer. For the dry seedling bed with high temperature in the seedling emergence stage, the mulch such as rice straw should be covered to avoid burning seedlings caused by direct sunlight. If there is a shortage of water, you can replenish it appropriately in the evening.

5. Actively prevent and control diseases and insect pests. According to the forecast of the occurrence of diseases and insect pests, control thrips, borer and rice blast.

IV. Management techniques of raising seedlings of single cropping rice in Northeast China.

In recent years, the seedling cultivation of single-cropping rice in Northeast China is affected by low temperature and humid climate. The temperature in March this year is the same as that in the normal year, and the temperature in some areas is on the high side, but the precipitation is twice as high as that in the normal year. It is expected that in the first ten days of April, the temperature will be lower than the normal year, the precipitation will be higher, and the number of windy days will be more.

At present, the following technical measures should be taken to raise rice seedlings:

1. Persist in raising seedlings in the garden. In order to ensure the temperature of seed germination and rooting, conditional areas must insist on raising seedlings in vegetable fields or courtyards, and try not to raise seedlings in Honda. If you can only raise seedlings in Honda, you must choose fields with high dryness, high content of soil organic matter and good permeability. It is best to build a platform with a height of more than 30 centimeters, and gradually improve it to make it a permanent seedling field.

2. Do a good job of seed treatment. Under the condition of low temperature in early spring, the seeds that have been accelerated to take root quickly, tiller early and emerge neatly after sowing, so the seed treatments such as seed drying, salt water selection, disinfection, accelerating germination and drying bud must be done strictly according to the procedure.

3. Prepare high quality nutrient soil. The ratio of nutritious soil is 60%-40% of guest soil with more than 3% organic matter content and 30%-40% of rotten, mashed and screened high-quality agricultural fertilizer, and the pH value of nutritious soil is adjusted to 4.5-5.0. Add 150 grams of ammonium sulfate, 300 grams of sodium superphosphate and 100 grams of potassium sulfate per mu of nutritious soil. Such as the use of seedling strengthening agent, omitting the link of adjusting acid and fattening. But pay attention to supplement nitrogen fertilizer between 3.5 and 4.0 leaves or apply marriage fertilizer before transplanting, at the rate of 40g to 50g per square meter.

4. Sparsely sowing strong seedlings. According to the different needs of ordinary dry seedlings, isolation layer seedlings and bowl plate seedlings, the sowing rate should be controlled at 150 to 300 grams per square meter.

5. Temperature control and seedling refinement. The period of high temperature often occurs in April and May in Northeast China. In order to prevent the seedlings from overgrowing, the bed temperature should be controlled at 25: 30 ℃ when the leaves are 1.5 to 2.0 leaves, and the bed temperature should be controlled at 20: 25 ℃ from 2.5 leaves to 3.0 leaves.

6. Prevent diseases and insect pests. Pay close attention to the occurrence of bacterial wilt and bacterial wilt at seedling stage and control it in time.