Hebei province and the US state of Iowa have been friends for 30 years, but 2013 could be a breakthrough year in their business relationship.

"We have a number of exchanges, including in education and culture," Iowa Governor Terry Branstad said on Thursday. "In the area of Chinese business, we're really just getting started."

About 75 companies from Hebei had a trade fair with 18 counterparts and associations from Iowa on Wednesday, an important part of Branstad's three-day visit to Hebei.

Most of the companies are involved in agriculture, including seeds, grain storage, equipment and services.

Yang Kai, owner of a corn-processing company in Ningjin county, said she likes the idea of doing business directly with suppliers from Iowa, the US state with the largest corn production.

"If their corn is better quality and cheaper, it sounds like a good choice for our company," she said.

"There should be more trade fairs, so we (small companies) can benefit more from the friendship with our sister state."

The trade fair also attracted large companies. "It's a good platform for us to talk with the state government, better for the future investment," said Xu Tie, spokesman for Yibo Foundation Group, who added that it has plans to expand its soy business from the state of Missouri into neighboring Iowa due to Iowa's high soybean yield.

In addition, Hebei advertised 50 projects seeking international cooperation to attract investment from Iowa on the 30th anniversary of their partnership.

The state and province have witnessed a tremendous increase in trade, as soybean, corn and pork — Iowa's major exports — are in great demand in China, said Branstad, who first visited China in 1984 and met President Xi Jinping, then a county government leader.

Like Yibo, many Hebei companies are pursuing opportunities to invest overseas.

"Efforts to encourage companies to invest outside of China have much to do with the growth in business maturity," the 67-year-old governor said. "China has made great economic progress and is now in the position to make investment outside."

Branstad said his state will provide sufficient support for companies in Hebei and other Chinese provinces, as well as reduce restrictions on agricultural imports and exports. "We talked about such issues with the Ministry of Agriculture after meeting with President Xi," he said.

China signed a contract worth $4.3 billion in 2012, importing 862 metric tons of soybeans from Iowa.

However, challenges to trade growth exist, especially in soybeans.

About 93 percent of Iowa soybeans are genetically modified, said Kirk Leeds, CEO of the Iowa Soybean Association. Many Chinese companies and residents doubt the safety of GM food.

One of three Hebei companies consulted the association during the trade fair said they will not import GM soybeans.

"It's safer than ordinary soy," the governor said, adding that it is resistant to weeds, insects and guarantees high yields. But it may take a long time to allay doubts.

Some Iowa companies have started to collaborate with Chinese institutes on technology, such as Dupont Pioneer, a corn seeds research company. Its office in China now runs a program aimed to help farmers increase productivity and profitability.