2021 Southern Early Rice Breeding and Transplanting Technology Guidance Opinions
By: Date: 2021-03-25 Categories: foodtechnology Tags: ,
   The”spring equinox” has passed, and the planting, raising and transplanting of early rice in the south has started one after another. Since mid-March, the temperature in most parts of southern my country has been higher than normal, which is conducive to early rice production. According to weather forecasts, the climate in the south is changeable from late March to early April, and the temperature fluctuates greatly. Some areas may experience”falling spring cold”, which will adversely affect early rice production. In view of the current climate characteristics and actual production conditions, the rice expert guidance group of the Ministry of Agriculture and Rural Affairs, together with the National Agricultural Technology Extension Service Center, put forward the technical guidance on the breeding and transplanting of early rice in the south, focusing on the cultivation of strong seedlings and timely transplanting to ensure that the feet are planted properly. To lay a solid foundation for the harvest of early rice.

   one is the best seed, sow seeds in time.”The seedlings are good for half a year”, and the cultivation of strong seedlings should be the key to early rice production. For fields that have not been sown, select high-quality, high-yield, and highly resistant varieties, soak the seeds before sowing to accelerate germination, and where conditions permit, it is recommended to raise seedlings in a greenhouse to improve the quality of seedlings and ensure the cultivation of strong seedlings. Seedling raising in the open air or in the field should pay close attention to the weather forecast. When the average daily temperature is stable through 12 ℃, avoid heavy rainfall and cooling periods, and seize the”cold tail and warm head” to rush to plant seeds in time. Early rice planting in the middle and lower reaches of the Yangtze River should be planted before the end of March, so as to be planted in an appropriate time. For fields that cannot be planted in time, select short-growing varieties to ensure the safe production of double-season late rice.

   The second is to adjust the temperature with water to resist cold and protect seedlings. Recently, temperature fluctuations in some parts of the south have been relatively large, and we must pay close attention to weather changes and strengthen the work of preventing cold in the seedling fields that have been sown. In case of low temperature, the ones that are not covered with film should be covered with small arch sheds or large sheds to prevent cold and heat preservation, and adopt methods such as”night irrigation and day drainage, sunny drainage and rain irrigation” to adjust the water and heat conditions of the seedling field to prevent rotten seedlings and ensure that the seedlings quality.

   The third is scientific regulation and cultivation of strong seedlings. From sowing to the one-leaf stage, the seedling field is mainly sealed and insulated, and the temperature in the shed is controlled at 30-35℃ to promote the rapid rooting of the buds and needles, and keep the surface moist during the period; in case of continuous sunny days with high temperature (≥35℃ in the film) , It is necessary to uncover both ends of the membrane to ventilate and cool to prevent high temperature from burning seedlings; in case of long-term rainy weather, open both ends of the membrane to ventilate once every 3-5 days at noon to reduce the humidity in the shed. At the stage of 1 leaf 1 heart to 2 leaf 1 heart, the temperature in the shed should be controlled at 26-32°C. If the temperature is higher than 32°C, the two ends should be opened in the morning or cloudy in the afternoon, and the seedlings should be ventilated during the day and night; If the continuous rainy weather suddenly turns fine, you should ventilate the seedlings before removing the film. Avoid suddenly removing the film and blindly applying quick-acting fertilizers such as urea. 3 leaves and 1 heart stage, cover day and night, it is not advisable to remove the membrane too early. 5-7 days before transplanting, use 1%-2%urea solution to sprinkle”bridging fertilizer” according to the color of seedlings, add clean water after application or apply body fertilizer 3-5 days before transplanting, generally apply 4 acres of seedling field. —5 kg of urea. For weak-growing seedlings, appropriately increase phosphorus and potassium fertilizers to maintain water balance and promote the recovery of growth.

  Fourth is a classification guide, transplanting in time. When the average temperature of the day passed 15°C stably, planting seedlings should be cleared up, and the transplanting should be completed before and after”Ching Ming” in South China. For machine-transplanted fields, it is necessary to improve the quality of plowing and field preparation, planting early and increasing the density at the right time. The seedling age is generally about 20 days and the longest is not more than 25 days. It is advisable to use a 25 cm row spacing seedling transplanter, planting more than 20,000 holes per mu. For hand-planting or throwing fields, the planting density should be ensured and the uniformity should be improved. The seedling age is generally 25-30 days. For high-yield fields, plant 20,000-25,000 holes per mu, 2-3 seedlings per hole for hybrid rice, and 2-3 seedlings per hole for conventional rice. There are 5-6 seedlings in the hole, and the basic seedlings per mu reach 50,000-60,000 and 100,000-120,000 respectively.

  Fifth is to strengthen management and balance growth. After planting, it is necessary to strengthen field classification management according to the basic seedling number, planting density, seedling growth status and weather changes, and adopt measures such as lightly exposing the field after live trees and applying tillering fertilizer early to promote early and rapid onset. For fields with insufficient basic seedlings and weak seedling quality, appropriate tiller fertilizer should be applied to increase the number of tiller seedlings and increase the rate of tillering ears. After planting, if it encounters low temperature and rain, it is necessary to irrigate the seedlings, postpone the application of tillering fertilizer, and enhance the ability of low temperature resistance. When the weather is clear, timely drainage, supplementary application of tillering fertilizer, and appropriate amount of phosphorus and potassium fertilizer.

  Source:Rice Expert Steering Group, Ministry of Agriculture and Rural Affairs, National Agricultural Technology Extension Service Center