Workers take samples of soybeans at a grain trading company in Suihua, northeast China's Heilongjiang Province, Oct. 25, 2022. Autumn grain purchasing work is underway in Heilongjiang. Photo: Xinhua

This photo shows sorted soybeans at a grain trading company in Suihua, northeast China's Heilongjiang Province, Oct. 25, 2022. Autumn grain purchasing work is underway in Heilongjiang. Photo: Xinhua

Workers take samples of newly purchased rice at a company of China Grain Reserves Group (Sinograin) in Harbin, northeast China's Heilongjiang Province, Oct. 28, 2022. Autumn grain purchasing work is underway in Heilongjiang. Photo: Xinhua

Soybeans are transferred to a railway freight container at a grain trading company in Suihua, northeast China's Heilongjiang Province, Oct. 25, 2022. Autumn grain purchasing work is underway in Heilongjiang. Photo: Xinhua

A worker mixes samples of soybeans at a company of China Grain Reserves Group (Sinograin) in Harbin, northeast China's Heilongjiang Province, Oct. 28, 2022. Autumn grain purchasing work is underway in Heilongjiang. Photo: Xinhua

A worker takes samples of soybeans at a grain trading company in Suihua, northeast China's Heilongjiang Province, Oct. 25, 2022. Autumn grain purchasing work is underway in Heilongjiang. Photo: Xinhua

Workers take samples of newly purchased soybeans at a company of China Grain Reserves Group (Sinograin) in Harbin, northeast China's Heilongjiang Province, Oct. 28, 2022. Autumn grain purchasing work is underway in Heilongjiang. Photo: Xinhua

A worker arranges soybeans on a truck at a soybean trading company in Suihua, northeast China's Heilongjiang Province, Oct. 25, 2022. Autumn grain purchasing work is underway in Heilongjiang. Photo: Xinhua

A worker checks newly purchased rice at a company of China Grain Reserves Group (Sinograin) in Harbin, northeast China's Heilongjiang Province, Oct. 28, 2022. Autumn grain purchasing work is underway in Heilongjiang. Photo: Xinhua