Photo taken on May 27, 2021 shows a self-propelled sprayer at work on a farm in Heihe, northeast China's Heilongjiang Province. (Photo by Lu Wenxiang/Xinhua)

Photo taken on May 27, 2021 shows a self-propelled sprayer at work on a farm in Heihe, northeast China's Heilongjiang Province. (Photo by Lu Wenxiang/Xinhua)

Photo taken on May 27, 2021 shows a self-propelled sprayer at work on a farm in Heihe, northeast China's Heilongjiang Province. (Photo by Lu Wenxiang/Xinhua)