How vegetable production can respond to heavy rainstorms

Since mid-June, the middle and lower reaches of the Yangtze River have repeatedly experienced widespread moderate to heavy rainstorms, causing large-scale waterlogging in various places. Vegetable bases everywhere have suffered disasters to varying degrees, causing major losses to planting enterprises and farmers. In order to restore current vegetable production and minimize disaster losses, the following response measures are specifically proposed.

Act quickly to drain water and reduce waterlogging

Clear the three ditches, remove waterlogged water, and ensure that rainwater drains quickly, that ditches are dry once the rain stops, and that there is no standing water in the bed surface or bed furrows. In areas with low-lying terrain and high inland river water levels, organize electric pump drainage to speed up drainage and lower the groundwater level. Flooded vegetable fields should have field water removed as early as possible to empty the ground, shorten the waterlogging time, and reduce the degree of damage. Achieve the goal that the "three ditches" are all connected, that ditches are dry once the rain stops, protect the healthy growth of vegetable roots, and reduce waterlogging damage. Reduce vegetable suffocation and death caused by standing water and waterlogging damage, and avoid vegetables being removed from the field prematurely.

Act quickly on management of vegetables still in the field

Promptly straighten lodging vegetables to reduce crowding against each other, and appropriately earth up and mound the roots. Promptly spray foliar fertilizer. After heavy rainstorms, the ability of vegetable roots to absorb water and fertilizer is poor, so foliar fertilizer should be sprayed promptly at this time. Generally, 0.2% monopotassium phosphate + 0.5% urea solution can be used to help vegetables quickly regain vigor. After rain, the soil becomes compacted; when the soil is slightly dry, carry out intertillage and loosening in time to improve soil structure and increase root vigor. After heavy rainstorms, manually spray water in time to rinse the leaves. Where there are water wells, it is best to use well water for sprinkler irrigation to wash away the soil adhering to stems and leaves.

For facility-cultivated vegetables or seedling greenhouses, rain-shelter cultivation can be adopted (that is, directly covering with roof film or directly covering with shade net, or one film plus one net) to provide shade and cooling, and to prevent heavy rain washing and sudden high-temperature exposure after the rain clears.

Forecasting and control of pests and diseases

Agricultural extension departments at all levels must effectively strengthen forecasting and prediction of pests and diseases, accurately grasp the occurrence and development trends of pests and diseases, increase guidance on integrated control, reduce pest and disease damage, and reduce losses. After heavy rainstorms, field temperatures are high and humidity is high, and plant resistance is weak, making pests and diseases likely. Timely spraying should be used for protection and control. Agents may include broad-spectrum pollution-free types such as carbendazim + deltamethrin or chlorothalonil + kung fu, and attention should be paid to the pre-harvest interval. The main pests and diseases include: root rot, fusarium wilt, downy mildew, phytophthora blight, anthracnose, powdery mildew, tobacco whitefly, bean pod borer, diamondback moth, and cotton leafworm. The main control measures include: promptly clearing ditches and draining waterlogging, unblocking the "three ditches," and lowering field humidity; promptly pulling out diseased plants (such as plants with root rot, fusarium wilt, phytophthora blight, etc.) and carrying them out of the field for deep burial; after the rain stops and the sky clears, carry out pesticide control: for root rot and fusarium wilt, use thiophanate-methyl 700-fold solution as a root drench; for downy mildew and phytophthora blight, use propamocarb 800-fold solution or curzate 500-fold solution by spray; for anthracnose and powdery mildew, use difenoconazole 1500-fold solution, or thiophanate-methyl 700-fold solution, or kresoxim-methyl 1500-fold solution by spray; for tobacco whitefly, use 4% abamectin-acetamiprid or bifenthrin 2000-fold solution, or 0.3 matrine 1000-1500-fold solution by spray; for bean pod borer, diamondback moth, beet armyworm, and cotton leafworm, use spinosad 1500-fold solution, or chlorfluazuron 1500-fold solution, or 1% emamectin benzoate 2500-fold solution by spray.

Timely replanting and changing crops

For some fields with dead seedlings and missing seedlings, actively guide farmers in replanting and changing to fast-growing vegetables. At the same time, effectively adopt rain-shelter measures and organize seedling raising for autumn-sown vegetables such as cabbage, cauliflower, chili pepper, tomato, eggplant, bottle gourd, cucumber, small pumpkin, lettuce, and celery. For emptied ground, rush to sow quick-growing vegetables: Chinese cabbage No. 5 seedlings, pak choi, summer Chinese cabbage, lettuce, leaf lettuce, Guangdong choi sum, leaf sweet potato tips, bamboo leaf vegetable, amaranth, celery, edamame, green beans, cowpea, radish, cilantro, spinach, etc.

Pay attention to preventing secondary disasters

In areas with high mountains and steep roads, pay attention to the dangers of debris flows and landslides, adopt certain defensive measures, and prevent secondary disasters. For facilities whose shed feet have loosened due to large rainfall and long soaking time, repair them promptly to prevent greenhouse collapse.