Staff members load packaged vegetables to be sent to the urban areas at a planting base in Chongming District, east China's Shanghai, April 19, 2022. Vegetable production and processing enterprises in Chongming District have been making efforts to assure the vegetable supply to the urban areas amid the recent COVID-19 outbreak in the metropolis. (Xinhua/Li He)

Photo taken on April 19, 2022 shows vegetables in a greenhouse at a planting base in Chongming District, east China's Shanghai. Vegetable production and processing enterprises in Chongming District have been making efforts to assure the vegetable supply to the urban areas amid the recent COVID-19 outbreak in the metropolis. (Xinhua/Li He)

Employees pack vegetables to be sent to the urban areas at a planting base in Chongming District, east China's Shanghai, April 19, 2022. Vegetable production and processing enterprises in Chongming District have been making efforts to assure the vegetable supply to the urban areas amid the recent COVID-19 outbreak in the metropolis. (Xinhua/Li He)

Staff members work in the office at a vegetable planting base in Chongming District, east China's Shanghai, April 19, 2022. Vegetable production and processing enterprises in Chongming District have been making efforts to assure the vegetable supply to the urban areas amid the recent COVID-19 outbreak in the metropolis. (Xinhua/Li He)

Employees transfer packaged vegetables to be sent to the urban areas at a planting base in Chongming District, east China's Shanghai, April 19, 2022. Vegetable production and processing enterprises in Chongming District have been making efforts to assure the vegetable supply to the urban areas amid the recent COVID-19 outbreak in the metropolis. (Xinhua/Li He)

An employee fixes the greenhouse and prepares to plant vegetables at a planting base in Chongming District, east China's Shanghai, April 19, 2022. Vegetable production and processing enterprises in Chongming District have been making efforts to assure the vegetable supply to the urban areas amid the recent COVID-19 outbreak in the metropolis. (Xinhua/Li He)

Employees pick tomatoes at a planting base in Chongming District, east China's Shanghai, April 19, 2022. Vegetable production and processing enterprises in Chongming District have been making efforts to assure the vegetable supply to the urban areas amid the recent COVID-19 outbreak in the metropolis. (Xinhua/Li He)

An employee picks cucumbers at a planting base in Chongming District, east China's Shanghai, April 19, 2022. Vegetable production and processing enterprises in Chongming District have been making efforts to assure the vegetable supply to the urban areas amid the recent COVID-19 outbreak in the metropolis. (Xinhua/Li He)