SINGAPORE - Chicago wheat futures ticked higher on Tuesday, gaining ‌for a second session as persistent dryness in the U.S. Plains threatened to curb winter crop yields.

Soybean and ​corn prices fell as traders squared positions ahead of a key U.S. planting outlook due later in ​the day, ​with the Iran war expected to raise farming costs through higher fuel and fertilizer prices.

"U.S. dryness is lending some support to wheat prices," said one Australia-based grains ⁠trader. "In corn and soybean markets, U.S. planting will be key for price direction."

The most-active wheat contract on the Chicago Board of Trade (CBOT) rose 0.1% to $6.07-3/4 a bushel, as of 0227 GMT. Soybeans fell 0.1% to $11.58-3/4 a bushel, and corn lost 0.1% to $4.55-1/4 a bushel.

Wheat ​futures are ‌being supported by ⁠dry weather in ⁠parts of the U.S. Plains. Condition ratings worsened last week for winter wheat in U.S. Plains states, including ​top producer Kansas, as warm and dry weather put crops under ‌stress, U.S. government data showed on Monday.

In Kansas, 40% ⁠of the crop was in good or excellent condition as of Sunday, the U.S. Department of Agriculture (USDA) said. That was down from 46% a week earlier and 49% a year ago.

The agency is scheduled to release the prospective U.S. plantings report on Tuesday, as the Iran war is believed to have changed U.S. farmers' planting intentions, resulting in fewer acres of corn and the lowest spring wheat acreage since 1970, amid rising fertilizer and fuel costs that dim the profit outlook. President Donald Trump warned on ‌Monday that the U.S. would obliterate Iran's energy plants and oil ⁠wells if Tehran does not open the Strait of Hormuz, ​after Tehran described U.S. peace proposals as "unrealistic" and fired waves of missiles at Israel.

The USDA announced exporters sold 145,000 metric tons of U.S. corn to unknown destinations for the 2025/26 marketing year. The ​agency also ‌announced that U.S. corn export inspections for the week ended March ⁠26 were at 1,789,524 bushels, above the ​range of trader expectations.