秋粮“一喷多促”技术要点
Currently, in the major production areas, corn is entering the silking and milky stage, mid-season rice is at the booting and heading stage, and soybeans are about to enter the flowering and pod-setting stage. This period is critical for yield formation and is also the window for “one spray, multiple boosts.” However, achieving a bumper harvest for autumn grains is still threatened by disasters such as floods, high temperatures, drought, cold damage, and pests. During the mid-to-late stages of autumn grain growth, mixing foliar fertilizers, regulators, stress resistance agents, and insecticides/fungicides for spraying can achieve multiple effects in one operation: promoting growth and development, boosting grain filling and maturity, aiding post-disaster recovery, and increasing yield. Adhering to the principles of “targeted measures, selecting optimal fertilizers and pesticides, precise spraying, and ensuring safety,” the implementation of “one spray, multiple boosts” is crucial to laying a solid foundation for a bumper autumn harvest.
1. Adapt to Local Conditions, Apply Targeted Measures
In Northeast China, spring corn is at the silking and milky stage, and spring soybeans are at the flowering and pod-setting stage. It is crucial to focus on threats such as waterlogging, low-temperature damage, early frost, and pests like corn borer, double-spotted leaf beetle, and northern corn leaf blight; soybean sclerotinia, soybean pod borer; and rice blast, sheath blight, and other diseases. In the Huang-Huai-Hai region, summer corn is about to enter the tasseling and silking stage, and summer soybeans are entering the flowering and pod-setting stage. The focus should be on waterlogging in the north and high temperatures in the south, along with pests such as southern rust, northern corn leaf blight, corn borer, fall armyworm, beet armyworm, cotton bollworm, soybean downy mildew, and soybean pod borer. In the middle and lower reaches of the Yangtze River, mid-season rice is at the booting and heading stage, and the focus should be on natural disasters such as high temperatures, drought, floods, and cold dew wind, along with diseases and pests such as sheath blight, rice blast, rice borer, and rice planthopper. In Northwest China, spring corn is mostly at the tasseling and silking stage, spring soybeans are at the pod-setting and grain filling stage, and summer soybeans are at the flowering and pod-setting stage. The focus should be on drought and early frost, along with pests such as double-spotted leaf beetle, spider mites, soybean pod borer, and soybean downy mildew. Based on the growth stages of corn and soybeans, as well as the occurrence of pests and natural disasters, a comprehensive implementation of “one spray, multiple boosts” should be tailored to local conditions.
2. Select Optimal Fertilizers and Pesticides, and Ensure Scientific Blending
To cope with natural disasters, areas with high temperatures and drought should spray potassium dihydrogen phosphate, water-soluble fertilizers with micronutrients, and drought resistance agents. Waterlogged areas should apply urea and potassium dihydrogen phosphate through foliar spraying after timely drainage. Areas threatened by early frost should spray phosphate-potassium fertilizers or liquid membranes. Corn growth regulators can include triacontanol, forchlorfenuron, brassinolide, indolebutyric acid, and others. Soybean growth regulators mainly include triacontanol, brassinolide, and indolebutyric acid. To address pests and diseases, corn fungicides can include azoxystrobin, tebuconazole, difenoconazole, and others, while insecticides can include chlorantraniliprole, emamectin benzoate, beta-cypermethrin, and others. Soybean fungicides can include azoxystrobin, pyraclostrobin, difenoconazole, and others, while insecticides can include chlorantraniliprole, beta-cypermethrin, and others. Rice fungicides can include tricyclazole, azoxystrobin microcapsules, isoflucypram, pyraclostrobin, and others, while insecticides can include triflumezopyrim, tetrachlorantraniliprole, chlorantraniliprole, and others.
3. Timely Spraying with Accurate Dosage
For timing, operations should be conducted when the wind speed is below level three, and the temperature does not exceed 30°C, generally before 9 a.m. or after 4 p.m. on rain-free days, avoiding the high-temperature period at noon. If moderate to heavy rain occurs within 24 hours after spraying, a supplementary spray should be done promptly. Nighttime operations using drones can be adapted to local conditions. Regarding dosage, when using drones, the spray volume should be at least 1.5 liters per acre, with the addition of appropriate spray adjuvants to enhance droplet deposition, anti-drift, and anti-evaporation properties. When using high-clearance boom sprayers or vehicle-mounted sprayers, the spray volume should reach at least 30 liters per acre.
4. Unified Operations and Ensuring Safety
Before operations, relevant regulations should be followed by making announcements in advance, and warning signs should be set up during operations to prevent poisoning and accidents involving humans and animals. Priority should be given to unified drone spraying, with flight speed controlled at 3–5 meters per second. The flight height should be adjusted according to the drone’s payload, with drones carrying less than 30 liters flying 2–3 meters above the crop canopy and those carrying more than 30 liters flying 3.5–4.5 meters above the canopy to prevent stem breakage during operations. Drones should take off and land away from obstacles and personnel, and operators should wear necessary protective gear, avoid downwind positions during spraying, and refrain from smoking or eating in the spraying area. For fields unsuitable for drone operations, high-clearance boom sprayers or vehicle-mounted sprayers can be used as appropriate. Before spraying, a comprehensive risk assessment should be conducted to prevent droplet drift causing non-target organism toxicity and surrounding crop damage. Small-scale trials should be conducted before large-scale pesticide applications.
