How to prevent high temperature heat damage to rice?

The causes and occurrence characteristics of high-temperature heat damage in rice

Rice is extremely sensitive to temperature during the budding and heading stages (i.e. 10 days before and after heading), and the optimal temperature is 25℃~ 30℃, daily average temperature above 30℃ will have adverse effects. If the sustained high temperature exceeds 35°C during the booting stage, the rice flower organs will be underdeveloped, the pollen will not develop properly, and the vigor will decrease; if the temperature exceeds 35°C during the heading and flowering stage, heat damage will occur, affecting the elongation of loose powder and pollen tubes, resulting in infertilization and failure. Empty shell kernels are formed, resulting in reduced seed setting rate, low thousand kernel weight, or even no harvest.

How to prevent high temperature heat damage to rice?

1. Choose high-temperature-resistant varieties. Different varieties have certain differences in the degree of high-temperature heat damage. Farmers should first select high-yielding and high-temperature resistant varieties during production to reduce the impact of high temperature on the grain filling and firmness of the varieties.

2. Timely sowing and transplanting should be based on the high temperature conditions in previous years, so that the best heading and flowering period of mid-season rice is arranged in mid-August to effectively avoid late July to August. Frequent high temperature and drought weather occurs in the early ten days of the year.

3. Deep water irrigation and water temperature regulation to maintain a certain water layer in the rice fields can significantly reduce the degree of yield loss under high temperature and drought conditions. Keeping the water layer in the field at 5 to 10 cm during the heading and flowering period can reduce the field microclimate temperature by 2 to 3°C and reduce heat damage. Especially for fields with water shortage and drought, water should be lifted for irrigation as soon as possible to increase field humidity and prevent the superimposed effects of drought and high temperature heat damage. Where conditions permit, day irrigation and night drainage or long-flow irrigation can be used.

4. Spray fertilizer outside the roots to enhance the stress resistance of rice. Spray 3% superphosphate solution or 0.2% potassium dihydrogen phosphate solution outside the roots, and spray foliar nutrient solution on the ridges. To enhance the resistance of rice plants to high temperatures and increase seed setting rate and thousand-grain weight. Or it can be used in combination with Quick Harvest during the heading period, which not only ensures the safe heading of rice, but also effectively shortens the earing period of rice, improves the ear-forming rate, makes the ears larger, has better seed-setting rate, higher yield, and matures earlier! And it can improve the tolerance of rice to extreme high temperatures and abnormal low temperatures. And no residue, non-toxic.

5. Prevent and control pests and diseases, promote healthy plant growth, and combine prevention of pests and diseases with heat damage. Rice mainly controls diseases and insect pests such as rice planthopper, rice leaf roller, rice blast, and sheath blight. When spraying fertilizers on foliage, the spray concentration and spray time must be mastered.

The concentration of the solution should not be too high, otherwise, too high a concentration will easily cause damage to the plant leaves and affect nutrient absorption; the best time is in the evening