BEIJING -- China's agricultural sector made a good start in the first quarter of 2018, but challenges and uncertainty remain, a senior official said Monday.

"The sound performance of the sector laid a solid foundation for the rural revitalization strategy," Wei Baigang, an official at the Ministry of Agriculture and Rural Affairs, told a press conference.

The primary industry's value-added output expanded 3.2 percent to 890.4 billion yuan ($141.3 billion) for January-March, with the pace of growth quickening from 3 percent during the same period in 2017.

According to Wei, per-capita disposable income for rural residents rose 6.8 percent to 4,226 yuan in the first quarter. Fixed-asset investment in the sector grew 24.2 percent to 290 billion yuan, accelerating from the 19.8-percent rise registered the corresponding period last year.

"Uncertainty, including changes in the global trade environment, international commodity market volatility and domestic macro-economic development, will affect the sector's performance," Wei said.

He added that there were challenges in ensuring sustained growth of rural incomes, while rising production costs and climate change would also weigh on the sector.

"The country will move to boost the development of agricultural product processing, provide more training for farmers and unveil more favorable policies to support the agricultural sector, rural areas and farmers," he said.