CANBERRA: Chicago wheat futures tumbled for a second day on Tuesday, falling to their lowest in eight weeks, as large crops in Argentina and Australia kept the market flush with supply. Corn futures also slipped, pressured by competition from cheap feed wheat that could reduce corn demand. Soybeans rose slightly after hitting seven-week lows on Monday due to concerns about the strength of US export demand and expectations for a bumper harvest in Brazil. “Global wheat prices remain under pressure due to Southern Hemisphere harvests and rising production estimates,” said Commonwealth Bank analyst Dennis Voznesenski, adding that bumper Argentinian production was pushing down Australian pricing. The Rosario Grains Exchange last week raised its production estimate for Argentina to 27.7 million metric tons from 24.5 million tons, while Australia is on track for its third-biggest harvest. Their crops round out a year of large harvests across major producing nations. The US Department of Agriculture (USDA) last week increased its estimates for global production and end-of-season stocks. There is no sign yet of significant production problems in 2026. The most-active wheat contract on the Chicago Board of Trade (CBOT) was down 0.8% at $5.16-1/2 a bushel at 0319 GMT, its lowest since October 24. On Monday, prices moved below their 50-day moving average, a bearish technical signal. CBOT corn eased 0.2% to $4.39 a bushel after falling to a three-week low on Monday. Soybeans rose 0.1% to $10.72-3/4 a bushel. The prices of all three contracts have slipped from highs in mid-November, when the market hoped a trade truce between Washington and Beijing would lead to China quickly buying large quantities of US crops, particularly soybeans. Wheat is down more than 7% from the November highs, while soybeans have fallen more than 8% and corn about 3%, as China’s purchases fell short of traders’ estimates. Wheat export prices in Russia, the biggest shipper of the grain, rose last week, analysts said. However, strong global export competition kept a lid on pricing. In soybeans, the US crush slowed more than expected in November but was still a record high for the month, according to the National Oilseed Processors Association (NOPA).