First, the characteristics of flooded rice In flooded rice, not only lodging, but also because of excessive soil moisture, poor ventilation, lower ground temperature, physiological activity has been greatly affected, and even died. The flooding can affect the life of rice. The time of submergence of rice plants is usually 2-10 days. The tolerance of different types of rice varieties is different, which is mainly reflected in the survival rate and root conditions of the stem, and also after the water outflow. The recovery performance is also related to the seedling quality before flooding, soil fertility and water quality, water depth and other conditions. For example, the hybrid rice tolerance is stronger than the conventional japonica rice, and the conventional japonica rice is stronger than the conventional japonica rice. When rice is flooded for 8 to 10 days at the seedling stage, the leaves are dry, but the growth can be resumed. The longer the flooding time, the more dead seedlings. After the water emerged, the seedlings became shorter, the number of tillers decreased, the base stems narrowed, and the black roots increased. The survival rate of long-lasting seedlings is generally high; The surviving rate of the storks is higher than that of the quails in the quails. After retreating, the pods have less pods and are more robust than the quails in the quails. When the rice is flooded from tillering to jointing, the fertility process is almost stopped. After the effluent, the height of the plant became shorter; the birth of the high position was increased, and the proportion of the spike was increased; the heading period was elongated, and the growth period was delayed. Within 10 days of flooding, the loss of production increased with the increase of the number of days of inundation, the loss of production within 4 days of submergence was small, and the loss of more than 4 days increased significantly until it was eliminated. During the booting period, submergence of the spikelets will occur for more than two days. The degree of damage will vary with the flooding time and depth of flooding, and will be affected by the flooded area. It will be flooded for more than 4 days, and the yield will be 41.9% higher than that without roof, and the water temperature will be high. It is heavier than the low damage. During flooding, the flooded soil in the flood season has poor ventilation, affecting root growth, and reducing weight and yield. Second, the flooded rice after the remedial measures of flooded rice can maintain seed production, decided to water early. The key to field management is to grab water and enhance management. (A) Remedial measures after planting seedlings 1. Clean seedlings in time. When the water retreats, the gums are used to wash the dead leaves and dead seedlings along with the direction of the water flow. Not only can they wash away the foliar dirt on the leaf surface, which is beneficial to the photosynthesis, but also can reduce the loss of rice leaves after repelling the dead leaves. The extent of the shed. Washing is best done when the seedlings are barely exposed. If the water is washed back into the half-length of the seedlings, the seedlings will have a high lodging rate after retreating and the growth will slow down significantly. 2. Control the water layer properly. After flooded seedlings, the stems and leaves were slender and tender, and the roots accumulated more due to hypoxia-reducing substances. The roots turned yellow and black, no white roots, and the viability was weak. Draining the water in the field as quickly as possible can increase the permeability of the soil and improve the rhizosphere environment. However, the late seedlings are vulnerable to high temperatures in the hot sun. To prevent the dew-seeded seedlings from wilting and lodging or even to die, they can take 10-13 deep water. Dewatering of Lucida after 4 pm and re-irrigation of shallow water in the early morning can effectively solve this problem. 3. Increase fertilization material timely transplanting. After shallow water irrigation, the application of 75 U of urea per hm2 can enhance the ability of the seedlings to restore their vitality as soon as possible, and promote the occurrence of more white roots. The transplanted plants were transplanted at a new hairy root length of 2.2 to 2.5 inches and a new leaf of about 1.5 leaves. Not only is it easy to pull maggots, but because of the white root elongation, the leaf area is small and the cultivar returns quickly after planting. The survival rate of the seedlings is greatly improved, and the general survival rate can reach more than 98%. 4. Use herbicides with caution. The use of herbicides before and after the flooding of seedlings will weaken the seedlings, so it is inappropriate to use herbicides in flooded fields. (b) Remedial measures after Daejeon 1. Grab the water as soon as possible. Clear up and clear the drainage system in time to reduce damage. During the submergence period it can tolerate, paddy fields are lined up for one day a day to minimize losses. At the same time, it should be identified whether or not the rice plant is dead. The symptoms are that the light-pushed rice plant is easily disengaged, the tillering section becomes soft, and the heart leaves are dead; conversely, if the root system is still alive, the tillering node is strong, elastic, and the heart leaves live. It indicates that rice plants still have vitality. In the order of drainage, the conventional row of paddy fields and rearranged hybrid rice fields. Different high and low fields, the first row Gaotian rear row low field. The flooded rice fields are more afraid of drought. If they are on cloudy days, they can take one-time drainage; in case of hot weather in the hot sun, the upper part of the rice plant should be exposed to the water surface, and the rice fields should be drained in the afternoon to avoid exposure. Restore growth. Drainage should also pay attention to the removal of floating debris to reduce rice seedlings crushing and seedling leaf rot. 2. Support Miao Dingmiao wash seedlings. Plant the lodging rice seedlings by hand and plant the roots to prevent them from lodging. Then, be careful when cultivating the seedlings to avoid injury. Then, sprays were used to spray and wash debris and other debris on the rice plant to restore its physiological functions such as photosynthetic respiration faster. 3. Ditch the water control timely. After the stagnant water in rice fields receded, the moisture in the fields remained saturated. Sewage drainage should be conducted so that the soil water in the field can seep into the ditch and reduce the moisture content of the field as soon as possible so that the floating mud formed by flooding will gradually sink to promote the growth of new roots. Adhering to the dry, wet and wet irrigation method not only ensures the water requirement of rice plants, but also ensures the ventilation of the soil, and promotes the occurrence of a large number of root systems in the upper nodes and a strong vitality. In case of low temperature during heading, deep water should be poured and the grouting should be solidified late to avoid premature water cut. 4. Increase the availability of fertilizer. During the submergence period, the vegetative organs of rice plants were damaged to varying degrees. After the effluent, the roots, leaves, and pods resumed growth. They required a large amount of mineral nutrients, and the loss of fertilizer in the original paddy fields was large. Therefore, the topdressing fertilizer was faster and the amount needed to be sufficient. Rice plants resumed growth as soon as possible, and they strived for large-spread production. After flooding from the till till the jointing stage, a method of chase and fill may be adopted. Fertilizer is mainly nitrogen fertilizer with phosphorus and potassium fertilizers; within 3 days after drainage, urea 150~187.5? or compound fertilizer 450~600 per hm2 can be applied. ?, Or the right amount of compound fertilizer. Submergence time is short, rice seedlings are lightly affected, and the amount of fertilizer applied is less; on the contrary, the amount of fertilizer is more appropriate. In order to promote the enlargement of the panicle type in the later stage, it is important to pay attention to the application of flower-enhancing fertilizer, and 60 to 90 hm2 of urea per hm2. When heading 20%, spray 7.5~15g “920†per hectare to promote heading and orderliness; in combination with spraying potassium dihydrogen phosphate during grain filling period, it will help to increase seed setting rate and 1000-grain weight, generally spraying 0.2% potassium dihydrogen phosphate 750~ per hm2. 1500?, every 5~7 days, spray 2~3 times. Flooded paddy fields during the booting period should be filled with foliar fertilizer. 5. Comprehensive control of pests and diseases. When the flooded rice grows, the leaves and pods born after the restoration of growth are more tender and green, and are vulnerable to damage by rice leaf roller. Delays in growth and development have increased the chances of invasion of rice planthoppers and rice borers. Therefore, we must grasp the timely control of pests, late attention to the prevention and treatment of rice blast.
Pukang Medical Instruments Co., Ltd. , http://www.xs-medicalbeds.com