Technical Guidance for Raising Rice Seedlings in Greenhouse of Northeast China in 2016

Abstract:

At present, the work of clearing snow and buckling shed in northeast China is progressing steadily, and rice seedling raising is about to begin. However, due to the high precipitation last winter and this spring, the soil moisture content is high, and the threat of low temperature and spring waterlogging in spring is greater. According to the current climate and production characteristics, we should base ourselves on early setting, early sowing, early soaking, early soil preparation and early transplanting, as well as the "five early" and "double snatching" of grabbing farming time and accumulated temperature, and strive to complete sowing by April 20 and transplanting by May 25, so as to lay the foundation for high and stable yield of rice. The following technical guidance is hereby put forward.

One is to make beds on high platforms and refine seedling soil.After clearing snow and buckling the shed, prepare soil to make beds before grabbing to ensure that seedlings are raised on schedule. It is advocated to plough frozen square, prepare frozen soil, and move it into the buckled shed room, and implement centralized warming, thawing and drying of frozen soil, ready for standby. Vigorously promote high-platform seedling. When the melting depth of the soil in the greenhouse is appropriate, immediately start to turn the ground, dry it, disperse the moisture and increase the temperature, and make a high-level seedbed, level and rake the bed soil to ensure that it meets the standard of dry seedling raising. Bed soil preparation should prevent undecomposed organic fertilizer from being mixed in, and should be evenly mixed with seedling strengthening agent. Mix well 1-2 days before loading, cover with plastic film and simmer. The thickness of the tray should be kept at 2cm, and the sowing and covering soil should be 0.5cm.

The second is to optimize the seed, the appropriate period of falling grain.According to local conditions, technical measures such as centralized high-platform drought breeding, three-film covering of greenhouses, and comprehensive warming of greenhouses are adopted to prevent low temperature and cold damage. Rice varieties with strong cold tolerance, strong resistance to rice blast and suitable maturity should be selected to prevent cross-region planting and ensure safe maturity. Before sowing, do a good job in seed cleaning, sunning, germination test, seed disinfection, soaking and accelerating germination and other pre-sowing treatments to ensure that the germination rate reaches more than 85% and that the seedlings are neat and strong. Cooperatives or large households with large machine-transplanting areas should sow seeds in due course and in stages. The sowing time shall be 30 days in advance according to the expected date of transplanting, and the method of less sowing and continuous sowing shall be adopted every day to ensure the appropriate transplanting of seedlings.

The third is to strengthen management and cultivate strong seedlings.In the management of seedbed, the temperature is mainly heat preservation, the optimum temperature is 25-28 ℃, and the maximum temperature is not more than 30 ℃. In case of high temperature above 30 ℃, the seedling shed should be opened to cool down. In the first leaf growth period, the temperature should be controlled below 28 ℃, and the optimum temperature is 25-28 ℃. One leaf has one heart to two leaves, and the temperature in the shed is controlled at 20-23 ℃, with the highest temperature not exceeding 25 ℃, so as to avoid the occurrence of early spike. Two leaves from one heart to transplanting, watering once, and applying marriage fertilizer 3-5 days before transplanting. Seedbed water management should not only highlight the "drought", but not "water shortage", to ensure the cultivation of robust seedlings. When the leaf tips do not spit water in the morning and evening, the newly expanded leaves curl at noon, and the surface of the bed soil is white, water should be replenished immediately.

The fourth is to prevent and control diseases and pests and bring medicine to the ground.Strengthen the prevention and control of diseases at the seedling stage, and use dithiocyanomethane, killing borer and allicin for seed soaking and disinfection to prevent and control the disease. Metalaxyl (or metalaxyl manganese zinc) is used alone or at the same time in the links of nutrient soil spraying, seed dressing and disinfection, and one leaf and one heart spraying to prevent and control the disease. In addition, strict management of fertilizer, water, temperature and humidity in seedling raising greenhouses, especially after the rice 1.5 the leaf stage, early ventilation and seedling refining should be carried out when the rain clears up, and acid adjustment and disinfection should be carried out on the seedling fields to prevent the occurrence of bacterial wilt. Before transplanting, take medicine to the ground to prevent leaf diving flies.

Five is fine soil preparation, timely transplanting.Dry soil preparation should be done to the end, to the edge and without leaving dead corners. The height difference in the same piece of land should not exceed 10cm, and the surface should be guaranteed to have a loose soil layer of 10-12cm. After 3-5 days of water soaking in the field, a paddy field tractor should be equipped with different soil preparation machinery. It is required that the land should be level off, the soil should be finely broken, the height difference in the same pool should not more than 3cm, and the surface should be 2-2-2-2-2-2-3, ensure high-yield period of high standards, high quality, high speed to complete rice transplanting.