After rice is flooded, remedial measures must be taken promptly
Remedial measures after rice is flooded
When paddy fields are flooded for 1 to 4 days below 25°C, the harm is not great; flooding for 1 to 4 days above 30°C can cause abnormal grain setting in rice; flooding for 1 to 4 days above 40°C can cause rice to wither and die, resulting in total crop loss.
When rice is flooded at the seedling stage, the seedlings become thin and spindly with yellowing leaves and generally are difficult to recover; at the tillering stage, the lower leaves necrose and the central leaves curl, and after the water recedes the leaves wither but generally do not rot; at the jointing stage, the plants become thin and weak and are prone to lodging and breaking; at the booting stage, resistance is weakest, making it prone to rotten ears and deformity, with reduced grain-setting rate; at the grain-filling stage, the lower leaves wither and yellow, the top leaves yellow, grains sprout on the ears, grain weight decreases, and grain quality deteriorates. Therefore, remedial measures should be taken promptly after paddy fields are flooded.
Drainage and leaf washing: Drain water promptly so that the rice seedlings are exposed above the water surface as early as possible, and promptly wash the mud off the leaves. When draining, do it gradually and slowly, not all at once, to improve the adaptability of the rice plants. Lodged rice seedlings should be promptly set upright, and rotten leaves and diseased leaves should be cut off.
Timely topdressing: Apply ear-grain fertilizer and foliar fertilizer promptly. According to the seedling condition, apply 3 to 5 kg of urea per mu as topdressing. At the flag leaf emergence and grain-filling stages, spray potassium dihydrogen phosphate as a foliar fertilizer, at 75 to 100 grams per mu, mixed with 50 kg of water, spraying 1 to 2 times.
Shallow-water intermittent irrigation in the later stage: After heading, shallow-water intermittent irrigation is preferable, to enhance root vigor, extend the lifespan of functional leaves, and strengthen the stress resistance of the rice seedlings. Intermittent irrigation means that after the first irrigation, the field is allowed to dry naturally for 1 to 2 days, then irrigated a second time, keeping it alternately dry and wet until maturity.
Timely control of diseases and pests: Generally, flooded paddy fields suffer severe disease and pest damage. From late July to early August, use agents such as jinggangmycin to broadly control sheath blight 1 to 2 times; 3 to 5 days before boot splitting, use propiconazole or penconazole-propiconazole to control rice false smut. At the same time, promptly control pests such as the third generation of the yellow stem borer, the rice leaf roller, and the brown planthopper.
When rice is flooded at the seedling stage, the seedlings become thin and spindly with yellowing leaves and generally are difficult to recover; at the tillering stage, the lower leaves necrose and the central leaves curl, and after the water recedes the leaves wither but generally do not rot; at the jointing stage, the plants become thin and weak and are prone to lodging and breaking; at the booting stage, resistance is weakest, making it prone to rotten ears and deformity, with reduced grain-setting rate; at the grain-filling stage, the lower leaves wither and yellow, the top leaves yellow, grains sprout on the ears, grain weight decreases, and grain quality deteriorates. Therefore, remedial measures should be taken promptly after paddy fields are flooded.
Drainage and leaf washing: Drain water promptly so that the rice seedlings are exposed above the water surface as early as possible, and promptly wash the mud off the leaves. When draining, do it gradually and slowly, not all at once, to improve the adaptability of the rice plants. Lodged rice seedlings should be promptly set upright, and rotten leaves and diseased leaves should be cut off.
Timely topdressing: Apply ear-grain fertilizer and foliar fertilizer promptly. According to the seedling condition, apply 3 to 5 kg of urea per mu as topdressing. At the flag leaf emergence and grain-filling stages, spray potassium dihydrogen phosphate as a foliar fertilizer, at 75 to 100 grams per mu, mixed with 50 kg of water, spraying 1 to 2 times.
Shallow-water intermittent irrigation in the later stage: After heading, shallow-water intermittent irrigation is preferable, to enhance root vigor, extend the lifespan of functional leaves, and strengthen the stress resistance of the rice seedlings. Intermittent irrigation means that after the first irrigation, the field is allowed to dry naturally for 1 to 2 days, then irrigated a second time, keeping it alternately dry and wet until maturity.
Timely control of diseases and pests: Generally, flooded paddy fields suffer severe disease and pest damage. From late July to early August, use agents such as jinggangmycin to broadly control sheath blight 1 to 2 times; 3 to 5 days before boot splitting, use propiconazole or penconazole-propiconazole to control rice false smut. At the same time, promptly control pests such as the third generation of the yellow stem borer, the rice leaf roller, and the brown planthopper.