Water Management in different growth stages of Rice

Rice has strict requirements for water conditions, and water requirements are different in different growth stages. In order to ensure stable and high yield of rice, scientific water management should be carried out according to different growth stages. 1. Irrigation in shallow water frequently at tillering stage.

Frequent irrigation in shallow water at tillering stage makes the stem of rice plant transparent, and sunlight can directly illuminate the stem of rice plant, increase water temperature and soil temperature, increase oxygen in soil, promote root development, improve fertilizer absorption capacity, promote early tillering, and improve tiller panicle rate. The depth of irrigation should be 3-5 cm according to weather conditions, and shallow water should be used on cloudy and rainy days. The hot and dry weather is a little deeper.

2. Drainage and drying the field at the foot seedling stage.

In the later stage of tillering, when the total number of tillers per mu of rice reaches 200000 ~ 230000, the field should be drained to control ineffective tillers, which is beneficial to the eugenic and rapid growth of main stem and large tillers, and achieve the goal of more ears, large ears, full grains and high 1000-grain weight. Sunning the field should grasp the weather characteristics, it is difficult to dry the field in cloudy and rainy weather, and the drying time can be longer, and we should pay close attention to drying the field early on a sunny day, or strive for a gap between sunny days, dry weather and poor water conservancy conditions.

3. regular irrigation in shallow water at the stage of young panicle differentiation.

In the period of young spikelet differentiation, if there is not enough water, the number of spikelets will be reduced, resulting in spikelet degeneration and grain number per spike; if irrigation is too deep, it will make the stem of the plant soft and easy to cause lodging. It is advisable to keep the water layer at 6cm to 8cm. In case of dry weather, the water layer can be slightly deeper, the overcast and rainy weather or the groundwater level is higher, or the fields with greedy rice seedlings can be irrigated with wetness to keep it dry and wet. During the period of young panicle differentiation, it is not tolerant to low temperature. In case of strong cold air, deep water should be irrigated and the deep water layer should be maintained to stabilize soil temperature and avoid low temperature affecting the development of young panicle. If there is a flood, it should be drained in time, and the seedlings should be washed while draining to remove the sludge from the rice leaves.

4. Keep the water layer at heading and flowering stage.

During heading and flowering stage, the water layer should be properly maintained to adjust the soil temperature, increase the air humidity among plants, promote the full heading of rice, and keep warm in deep water in case of low temperature.

5. Dry-wet alternation in milking stage.

Milking stage is an important period of grain filling, in case of drought and lack of water, it will cause premature senescence of leaves and affect grain fullness; if the deep water layer is maintained, it will affect the root activity in the later stage, resulting in poor grain filling. Therefore, in the milking stage, it is appropriate to keep the soil moist, so that there is no stagnant water, no shortage of water, alternating between dry and wet, so as to make the grain full. After the yellow ripening period, the water demand is reduced. In this period, stagnant water in the field must be avoided to promote maturity and facilitate harvesting.