Updates for market close

By Heather Schlitz

CHICAGO, May 28 (Reuters) - Chicago grain and soybean futures gained on Thursday as investor doubts about prospects for a deal to reopen the Strait of Hormuz drove oil prices higher, supporting prices of crops used to make biofuel.

The most-traded wheat contract on the Chicago Board of Trade Wv1 settled 1-1/2 cents higher at $6.24 per bushel.

CBOT corn Cv1 ended 3-1/4 cents higher at $4.55-3/4 per bushel, and soybeans Sv1 settled 9-1/4 cents higher at $11.94-1/2 per bushel.

"I think the grains are watching energy prices overall, but there are so many ups and downs and swings that the market is tired of reacting to every little change," said Randy Place, analyst at Hightower Report.

Oil prices have been volatile in recent sessions as traders parse conflicting signals on the possibility of an end to the three-month Iran war and a potential reopening of the strait. Traffic through the maritime chokepoint remains at a small fraction of the pre-war level. O/R

Along with support from rising crude oil futures, the soybean complex was buoyed by a brief strike in Argentina of oilseed workers.

The strike, which ended hours after it began, had threatened to halt operations at crushing plants in the world's biggest exporter of processed soy products.

Analysts say the poor condition of drought-afflicted U.S. wheat has been priced in and the market is looking ahead to harvest pressure on prices and a global oversupply.

Consultant Sovecon on Wednesday raised its 2026 wheat production forecast for leading exporter Russia to 90.3 million metric tons from 89.7 million tons.

"The wheat market is fighting a bearish seasonal trend right now. U.S. prices are uncompetitive export-wise, so a price pullback doesn't generate new export demand," Place said.