Techniques for raising seedlings of rice in large and medium sheds

(i) Selection. It is necessary to select high-quality, high-yield, disease-resistant, and middle-spike heavy-duty varieties that have superior delivery ability. The first accumulated temperature area is represented by Wuchang and Tailai, and Wuyoudao 1, Songjing 2, Caneline 140, Wudao 3 and Mudanjiang 19 are suitable as the main cultivars; the second accumulated temperature zone is Ning'an, Representatives of Founder, Yanshou, Huachuan, and Suihua are suitable for Japonica rice No.8, Tiexian No.112, Fujiguang, Hejiang No.19, No.4 and No.10, etc.; the third accumulated temperature zone is Mulan. Representatives from other places are suitable for the main cultivars such as Kongyu 131, Sanjiao No. 3, Longjing No. 8 and Shangyu 397.

(b) as a bed. When the soil in the shed melts more than 10 cm, it is turned into a seedbed. Before going to the ground, the farmer's manure should be fully and thoroughly cooked, and the soil should be finely crushed and the roots and debris should be unearthed. Leave the trail in the middle of the shed and make rectangular seedbeds on both sides of the trail. Around the seedbed, 5 cm tall cymbals are built. If seedlings are to be used for seedlings, it is important to note that the effective width of the seedbed coincides with the combined width of the trays in order to avoid wasting seedbeds.

(c) Preparation of nutritious soil. Fertile soils with fertile upland soil and decomposed pig manure are mixed and mixed in a ratio of 7:3, or mixed with upland soil, decomposed peat and pig manure at a ratio of 4:4:2, with 6-8 holes before sowing. Mesh sieve, then add strong agent to mix thoroughly before use. 20 kg of bed soil per square meter, evenly mixed into the bed tillage layer 3 cm; seedling plate nursery; such as 561 hole tray, about 400 trays per hectare of paddy fields (due to the difference in the rate of transplanting and transplanting), each The dumplings use about 2 kg of nutritious soil.

(d) Seed treatment. Sowing before sowing for 3 days, use salt water or yellow mud water with a specific gravity of 1.1-1.3 to select the species, remove the cereals, wash and soak with Shibaoke (water temperature 15-16°C, soaking for 5-7 days); 30 after soaking Break the chest at -32°C. When 80% of the seeds are broken, the temperature is lowered to 25°C to germinate. When the bud grows to 1-2mm, the temperature drops to 15-20°C and the shoots are ready for sowing.

(e) sowing. Before sowing bed soil to be poured through the bottom water, rubbing the bottom of the hole to be in close contact with the bed surface, can not leave gaps, each hole seeding species of 2-3 tablets, sowing seedlings with a drawer, but also artificial sowing. Artificial sowing is to first put the nutritious soil into the cavities of the carcass disk and remove the nourishment soil. Lightly water it with a fine watering can. After the nutrient soil is solid, artificially sow and sow the seed that has not entered the acupuncture point. Sweep into the acupuncture point, and adjust the uniform, cover soil 0.5 cm, and finally close the herb, cover the film.

(6) Putian management. The first is to prevent the excessive temperature in the shed from raising weak seedlings, and the second is to prevent low temperature and water shortage from growing into young seedlings. The third is to prevent death caused by blight caused by severe temperature changes. The larvae are generally 35 to 40 days old, and the bred bryo of 4.5 leaves with an average of one tiller. The suitable temperature required for seedlings at different fertility stages varies from sowing to seedling emergence at a lower temperature. The medium and large sheds are mainly sealed and insulted. When the seedlings meet with a “top cover” phenomenon, the topped cover soil should be broken in time and lightly watered. Cover it with soil again. Remove the film after the seedlings are out. The seedling temperature of one leaf stage is controlled at about 25°C, the plant height is between 4.5 and 5.5 cm; the temperature between two leaf and one heart is controlled at 20-25°C, and the plant height is 7.5-8.5 cm; the temperature of the three-leaf and one-heart period is controlled at 20°C. High 12.5-13.5 cm. Water management should be short of water, especially water management after 2.5 leaves. Since carcass pan seedlings have poor drought resistance, watering should be taken care of. When the dewdrop of the seedlings of the seedlings is reduced or the leaves of the noon are rolled in the morning, it is necessary to water in the morning or the evening in time to prevent the seedlings from being burnt at high temperatures. The watering must be sprayed slowly and reciprocally. The seedlings began to ventilate and strengthen the seedlings at the beginning of one leaf and promote control. Generally, the ventilation is started from 9-10 o'clock in the sunny days, and the membrane is kept closed at 14-15 o'clock. The ventilation time and ventilation volume should be based on the temperature. When the temperature is low, ventilation time and ventilation volume should be reduced. CAUTION Ventilation openings should be on the side of the leeward. When each ventilation, slowly open the ventilation openings and gradually increase the ventilation volume. When the temperature is high during the late period of the rearing period, the two sides can be ventilated at the same time, and the ventilation film can be ventilated overnight or evacuated 3 to 5 days before transplanting. Disease prevention should be based on prevention of blight and blight. In the 1.5-2.5 leaf stage of the seedlings, saplings, evil spirits, or disease-bearing nets are used to prevent green and blight, or in combination with watering, spraying 1-3 times. Acidified water with a value of 4 prevented blight and sprayed with fresh water. After the 3 leaf stage of seedlings, if there are general chlorosis and yellow fertilizer in the leaves, potassium dihydrogen phosphate or ammonium sulfate 2-3 kg can be used per 100 square meters of seedbed, 200-300 kg of water can be mixed with 100 times liquid foliar spray. Spray water to prevent burning seedlings after spraying.