SINGAPORE, Feb 3 (Reuters) - Chicago soybean futures edged lower on Friday, but were poised for weekly gains supported by uncertainty over supply from top producer Argentina amid dry weather conditions.
Wheat and corn also fell, with corn extending losses to a second consecutive session.
The most-active soybean contract on the Chicago Board of Trade (CBOT) lost 0.5% to $15.27 a bushel, as of 0547 GMT.
Wheat gave up 0.3% to $7.58-3/4 a bushel and corn lost 0.3% to $6.73-1/2 a bushel.
For the week, soybeans are up 1.2%, corn has declined about 1.4%, and wheat has gained 1.2%.
Argentina's Buenos Aires grains exchange warned on Thursday that despite recent rainfall, a historic drought over the country's core agricultural region could still negatively impact the current soybean harvest.
The exchange's report indicated that 46% of soybeans were in a poor or very poor condition, down from 54% last week.
In Argentina, more rains are needed to avoid additional crop stress, but the weather forecast for the next 10 days to 2 weeks continued to look mostly dry with only scattered rain events, supporting futures prices due to supply concerns, commodities research firm Hightower said in a note.
Incoming rainfall in Brazil next week and on into the mid-month should be greatest from the center-west into center-south production areas, translating into a very good environment for ongoing crop development, Terry Reilly, senior analyst at Futures International said in a note, adding that may slow early season soybean maturation and harvest progress.
Grain markets are watching for evidence of a pickup in demand in China, the world's biggest soybean importer, following the week-long Lunar New Year holiday.
A weekly report from the U.S. Department of Agriculture (USDA) on Thursday showed that export sales of soybeans totalled 928,000 tonnes in the week ended Jan. 26, down from 1.275 million tonnes in the week prior.
The report also showed corn export sales of 1.756 million tonnes and wheat export sales of 168,900 tonnes.
U.S. farmers expanded plantings of winter wheat by 11% from a year ago to an eight-year peak, encouraged by high prices tied to concerns over food supplies following Russia's invasion of major wheat producer Ukraine, as well as relatively low input costs and expanded crop insurance programs.
Global commodities trader Cargill Inc closed its grain elevator in Portage, Indiana, on Tuesday, according to the company's website.
Commodity funds were net buyers of CBOT soybean, soymeal, soyoil and wheat futures contracts on Thursday, and net sellers of corn futures contracts, traders said.
A global stock rally ran into resistance in Asia, as disappointing earnings from U.S. tech giants undermined sentiment, while the dollar regained some of its footing ahead of a key U.S. non-farm payrolls report. (Reporting by Matthew Chye; editing by Eileen Soreng)
