Practical advice on self-rescue for vegetable production after rain disasters

Recently, most areas of Quzhou County have experienced heavy rainfall accompanied by strong winds, with flooding disasters in some places, waterlogging in some farmland, damage to some agricultural facilities and farmland, and lodging of crops, causing adverse effects on agricultural production. In order to scientifically respond to the harm caused by this rain disaster to the county's vegetable production, minimize losses, and ensure vegetable supply and vegetable growers' income, technicians from the County Agriculture and Animal Husbandry Bureau went deep into Quzhou Town, where vegetable planting is concentrated, to inspect the disaster situation, guide production self-rescue, and put forward the following technical recommendations:

I. Open-field vegetables

(1) Promptly drain accumulated water and carry out intertillage and soil loosening. For plots that were less severely affected, drain the drainage ditches and channels of the vegetable fields as soon as possible, remove accumulated water, and clear away the silt and sand deposited in the fields by flowing water. After the soil in the vegetable fields is slightly dry, carry out intertillage and soil loosening in time to improve the soil's physical properties, prevent soil compaction, improve soil aeration and water infiltration capacity, promote root growth and development, and restore growth as soon as possible.

(2) Replant and change crops as early as possible to reduce economic losses. For vegetable plots that were more severely affected and whose seedlings were partially or completely drowned or destroyed, promptly carry out emergency harvesting and replant other vegetables. Cabbage, fast-growing leafy vegetables, and others can be planted. Where seedlings are available, cauliflower, cabbage, head lettuce, and others can be transplanted. Fast-growing leafy vegetables such as fennel, rapeseed, heat-tolerant spinach, and loose-leaf lettuce can also be selected.

(3) Strengthen field management to promote high and stable yields. After heavy rain, promptly tie up and support lodged vegetable plants, reinforce vegetable trellises, remove residual branches and diseased fruits, clean off mud and sand adhering to stems and leaves, and timely earth up around the roots to enhance lodging resistance. Because field fertilizer loss after heavy rain is relatively serious, and because vegetable root activity declines after being flooded, reducing the ability to absorb fertilizer and water, timely topdressing is necessary: First, soil topdressing. Flexibly control the amount of fertilizer applied according to different plots. Plots that were severely waterlogged and suffered relatively large fertilizer loss should be supplemented more appropriately, while the opposite applies to others. Generally, applying 5-10 kg of urea and 10-15 kg of superphosphate per mu is sufficient. Leafy vegetables should be mainly given nitrogen fertilizer, with thin applications applied frequently; melons, beans, and solanaceous fruits should be given nitrogen, phosphorus, and potassium in combination. Second, foliar spraying. A mixed solution of 0.3%-0.5% potassium dihydrogen phosphate and 0.3% urea, among others, can be sprayed on vegetable leaves, once every 7-10 days, for 2-3 consecutive sprays, to increase yield and prevent premature plant aging or the occurrence of deformed fruits.

(4) Seriously carry out the prevention and control of diseases, pests, and weeds. High-temperature and high-humidity weather is conducive to the occurrence and spread of pathogens, so disease, pest, and weed control should be carried out in time. First, fungicides such as carbendazim or thiophanate-methyl can be sprayed 1-2 times to prevent pathogens from invading through wounds. Second, keep the vegetable garden tidy and promptly remove field weeds and diseased plants.

(5) Strengthen the production management of summer and autumn sown vegetables. For summer and autumn sown vegetables such as Chinese cabbage and radish, disease-resistant, high-yield, and storage-tolerant varieties should be selected. For example, for Chinese cabbage, Beijing New No. 3, Youlü No. 3, and others can be selected. At the same time, drainage and waterlogging prevention facilities should be well built in vegetable fields to ensure smooth drainage when disasters such as heavy rain occur.

II. Facility vegetables

(1) Remove accumulated water in the facilities and disinfect the soil. For greenhouses with accumulated water that were less severely affected, quickly remove the accumulated water, and use liquids such as 50% carbendazim and 40% formalin for soil disinfection to kill pathogens in the soil and prevent soil-borne diseases.

(2) Raise seedlings and replant in time to accelerate production recovery. For greenhouses that were more severely affected and whose seedlings were drowned or destroyed, disinfect the soil in time and then replant or transplant. For damaged seedlings, promptly spray a fungicide and foliar fertilizer once to prevent pathogens from invading through wounds, and at the same time apply root-promoting fertilizers by irrigation to help vegetables recover growth as soon as possible.

(3) Take favorable measures to repair damaged greenhouses. For greenhouse walls damaged by rainwater scouring, earth up the walls, reinforce them, and cover them with film or non-woven fabric to avoid a second scouring. At the same time, promptly replace and reinforce key parts such as damaged upright posts inside the greenhouse and the rear slope of the greenhouse. Check the greenhouse film for damage, repair any holes in time, and add pressure film lines and secure the greenhouse film. To prevent hail damage, insect nets or shade nets of the same length and width as the greenhouse can be covered over the greenhouse, pulled tight and kept at a certain distance from the greenhouse film, so as to reduce the impact of hail on the greenhouse film, avoid the greenhouse film being broken by hail, and prevent damage to vegetable crops.

(4) Dig drainage ditches to ensure smooth drainage. Drainage ditches about 0.5 m wide and about 0.3 m deep can be dug around the greenhouse to ensure that water flowing down from the greenhouse is drained away in time after heavy rain comes again, preventing rainwater from flowing backward into the greenhouse.

(5) Strengthen cultivation management and prevent the occurrence of diseases and pests. After heavy rain, humidity is too high, and various diseases are likely to breed. Strengthen the control of temperature and humidity in the greenhouse, increase ventilation, reduce greenhouse humidity, and lessen the occurrence of diseases. Seize sunny weather to promptly spray fungicides such as chlorothalonil and thiophanate-methyl 1-2 times to prevent pathogens from invading through wounds. Soil-borne diseases should mainly be controlled by root irrigation. At the same time, physical control methods such as insect nets and insect-attracting sticky traps should be used to reduce the occurrence of pests. If pests are found, biological pesticides and high-efficiency, low-toxicity, low-residue pesticides should be used in time for control to ensure product quality and safety.

Quzhou County Agriculture and Animal Husbandry Bureau Liu Xiaoxia