SYDNEY, May 1 (Reuters) - U.S. rice futures bounced in Asian trading on Thursday, reversing sharp falls in Chicago on Wednesday, which were triggered by easing concerns about a worldwide shortage of the food staple.

Corn, soybeans and wheat also posted moderate gains on Thursday.

U.S. rough rice futures had fallen by their maximum limit of $1.15 a hundredweight for three straight days before bouncing on Thursday.

At 2351 GMT, Chicago Board of Trade July rough rice futures <RRN8> were up by 0.55 percent to $21.87 a hundredweight from the close in Chicago on Wednesday.

After falling by 5 percent in Chicago on Wednesday, to $21.78 a cwt at the close, U.S. rice futures opened weaker on Thursday morning but found renewed strength soon after the start.

This followed sharp falls by rice futures this week after top exporter Thailand said it would gradually release 2.1 million tonnes of stockpiled rice in the domestic market and maintain its 2008 export target of at least 9 million tonnes.

Rice prices had earlier surged to record highs around the world on global shortage fears, reinforced by export curbs by key Asian producers.

The weaker U.S. dollar after the Federal Reserve rate cut on Wednesday had lent mild support to Chicago grains prices overall, Garry Booth of commodities broker MF Global said on Thursday.

May corn <CK8> was up 0.62 percent at $6.04 a bushel, while May soybeans <SK8> was up 0.56 percent at $13.09 a bushel. May wheat <WK8> was up 0.64 percent at $7.92-1/4.

Continued concern over wet weather delaying plantings of U.S. corn was showing up in Asian markets, Booth said.

Soybean prices have also been rising on fears that farmers in Argentina might resume a strike as they negotiated with their government over a hike in export taxes. (Reporting by Michael Byrnes; Editing by Ben Tan) (([email protected]; +61-2-9373 1825; Reuters Messaging: [email protected])) Keywords: MARKETS GRAINS/