U.S. corn futures are poised to open lower Thursday on pressure from outside markets, with strong export sales and planting concerns limiting losses.

Chicago Board of Trade futures are called 7 cents to 9 cents lower. In overnight trade, corn for May delivery at the Chicago Board of Trade was down 8 3/4 cents, or 1.2%, to $7.46 3/4 per bushel.

After setting a fresh all-time record of $7.83 3/4 Monday, the market has been dragged lower this week by profit-taking and pressure from other commodities, including crude oil, due to worries about the global economy and demand.

In particular, worries about inflation in China, which could prompt the government to enact measures to control growth that could curb commodity demand, has weighed on the markets, analysts said.

A sharp drop in grains prices earlier in the week "showed us conclusively that Macro-Fundamentals surrounding world growth, higher energy prices, and higher interest rates can indeed 'trump' the bullish Micro-Fundamentals of corn planting delays," said Mike Zuzolo, president of Global Commodity Analytics and Consulting.

But supply and demand factors in the corn market will likely keep a floor under prices for the foreseeable future, analysts said. The U.S. Department of Agriculture projects extremely low stockpiles by the end of the summer, which is supportive to nearby contracts.

Longer-term, traders and analysts are nervously watching U.S. corn belt weather with concern about whether planting could be delayed. Earlier planting is typically better for final yields, as it reduces the chance the crop will still be developing when the season's first frost hits.

The Telvent DTN weather forecast calls for rain, storms and even snow in the Midwest this week, with the potential for more rains next week that could stall planting. Meanwhile the northern U.S. Plains are dealing with flooding that will also slow field work and, according to some analysts, ultimately limit the amount of corn that is planted.

Weekly export sales topped trader expectations. The USDA reported weekly net sales of 1.1 million metric tons, including 848,000 for the 2010-11 marketing year and 253,500 for the 2011-12 year. The old crop sales in particular bested trader expectations.

Traders are looking for signs that the historically high corn prices are choking off demand, which is deemed necessary to avoid a supply crisis later in the summer.