How to prevent and control high-temperature heat damage in rice? A detailed explanation of practical technical measures

Rice high-temperature heat damage generally refers to an agrometeorological disaster during the heading and grain-filling stage of rice, when the air temperature exceeds the upper limit of the normal growth temperature for rice, affecting normal flowering and grain setting, causing an increase in the rate of empty and blighted grains and leading to reduced yield or even total crop failure. Xuzhou has compiled for everyone the technical measures for preventing and controlling rice high-temperature heat damage, hoping it can help you.

First, adopt the measures of irrigating by day and draining by night or sprinkler irrigation to lower the temperature of the panicle layer and protect the crop from high-temperature heat damage.

Experiments show that when the high temperature is above 35°C, after irrigating the field with an 8-10 cm water layer, the air temperature around the panicles drops by about 2.2°C, and the relative humidity increases by 3-4 percentage points. If extreme high temperature is encountered in the late flowering stage, the method of spraying water on the panicle layer to lower the temperature can also be adopted.

Second, apply fertilizer by foliar spraying to enhance the rice's ability to resist stress and prevent disasters.

When high temperature is expected, at the booting stage (15-10 days before flowering), combined with the prevention and control of diseases and insect pests at the heading stage, spray 50 milliliters of Kangduole 600-fold solution per mu on the leaves to prevent and eliminate the physiological damage from high temperature and strong light.

If flowering has already begun or is about to begin, spraying 50 milliliters of Huaduole 600-fold solution per mu on the leaves can effectively alleviate the damage to flowering and pollination from high temperature. In addition, spraying a 3% superphosphate solution or a 0.2% potassium dihydrogen phosphate solution, plus nutrient liquid fertilizers such as Handilong and Meizhouxing, has the effect of reducing high-temperature heat damage, increasing the seed-setting rate and the 1000-grain weight.

For those that have already suffered high-temperature heat damage and severe yield reduction, experts have given remedial measures: for those that encountered high-temperature heat damage at the heading and flowering stage, if the seed-setting rate is below 10% and the per-mu yield is less than 100 kilograms, the stubble can be cut to cultivate ratoon rice.