Heavy rain has swept across east China's Anhui Province as sudden temperature drops hamper crop growth.

Persistent downpours since Monday have caused the water level in some sections of the Huaihe River to exceed a warning line, according to Anhui Provinces' Department of Water Resources.

The water level in some sections of the Yangtze River in Anhui has risen by up to 0.36 meters, the department said.

Meanwhile, from Monday to Wednesday the average temperature in Anhui dropped by eight degrees Celsius, meteorological authorities said.

The sudden temperatures drops may hinder the growth of wheat, rape, and rice seedlings, said Niu Yunsheng, head of the provincial agriculture bureau.

The tasseling of some wheat in Mingguang City may be delayed, said Xu Zetao, head of the seed management station in Mingguang City, which planted more than 800,000 mu (53,333 hectares) of wheat.

The Anhui Provincial Finance Bureau has allocated 7 million yuan to support the spring plowing in 32 counties.

While visiting Anhui, Chinese Premier Wen Jiabao recently said grain production is important to stabilize prices and to support the economy as a whole.

Separately, by Tuesday, the lingering drought in southwest China had parched more than 93 million mu of farmland in the provinces of Yunnan, Guizhou, Guangxi and Sichuan, the Office of State Flood Control and Drought Relief Headquarters said.