Chicago wheat futures rose for a third consecutive session on Thursday to its highest in more than a week, helped by concerns over downgrades in the outlook for Russian grain crops.
Corn, a feedstock for biofuel ethanol, was flat after closing lower amid persistent concerns over weak ethanol demand.
"Wheat seems to be getting (a) bit of support from downgrades in the Russian crop outlook, but supplies are still ample given the lower demand due to the coronavirus," said Ole Houe, director of advisory services at brokerage IKON Commodities.
The most-active wheat contract on the Chicago Board of Trade rose 1.4% to $5.20-3/4 a bushel by 1054 GMT, having climbed to its highest since May 11 to $5.21-1/4 earlier.
December wheat futures on Paris-based Euronext rose 0.5% to 190.75 euros a tonne, having hit their highest since late February.
Russia will harvest about 120 million tonnes of grain in 2020, slightly less than in 2019 and lower than a previously expected 125.3 million tonnes as yields are going to decline.
Russia and Ukraine - major Black Sea wheat exporters - were hit by dry weather in April, as was Europe, though May rain fixed most of the damage for the upcoming crop.
A decline in US winter wheat crop ratings and a lower-than-expected crop outlook during a Kansas wheat tour also buoyed the market.
Corn was flat at $3.19-1/2 a bushel, having closed down 0.5% in the previous session and soybeans dipped 0.3% to $8.44-3/4 a bushel, having firmed 0.5% on Wednesday.
China will start offering for sale 4 million tonnes of corn from its state reserves on 28 May, a move long awaited by the market as supplies of the grain tighten.
In the United States, however, a huge corn acreage is expected to be planted this year.