Deputy Prime Minister Barnaby Joyce has backed concern about levels of foreign investment in Australian farmland, saying it's about patriotism.

"There's one thing that people are not prepared to do and that is die for a rented country," he told the National Farmers' Federation congress in Canberra on Wednesday.

Mr Joyce used a speech at the conference to spruik the government's foreign land register, saying it's important to know who owns Aussie land.

The agriculture minister said it was one of the nation's most precious assets and losing sight of that would be forgetting people.

Australia was not losing foreign investors - they were "lined up at the door".

"It's the whole essence of patriotism - the love of one's country is best delivered when you own that country," he said.

In a wide-ranging speech to farmers, and in the presence of Chinese officials, Mr Joyce also cautioned about the effects of socialism and communism.

Mr Joyce opened his address about innovation in the farming sector warning of the socialisation of assets, critiquing Labor for various policies.

"There's a word for this - it's called communism."

In the audience was the Chinese ambassador to Australia.

The deputy prime minister later defended his comments saying that China was moving very quickly to a market-based economy.

"They believe in private enterprises," he told reporters.

Earlier, the conference heard from mining magnate Andrew Forrest spruiking premium Australian food and produce to the Chinese market under a national brand.