Spot soybeans sold for 1,750 Argentine pesos ($350) a ton at the Rosario Grain Exchange Thursday, down from ARS1,843 a week ago. Soy for May delivery sold for $320 per ton, down from $334 a week ago.
Despite the weakness, tight spot-soy supplies and solid demand from local crushers helped to stem the losses, the Rosario Exchange said.
Argentina's soybean crop was battered by drought last season, causing production to fall sharply. With the new crop still a month or so from coming to market, stocks are dwindling.
Argentina is the world's top soymeal and soyoil exporter and ranks No. 3 in soybean exports.
Global markets are watching the Argentine crop closely and fretting over recent dry weather, as bumper crops are needed from both Argentina and Brazil this season to rebuild international stocks.
Meanwhile, spot corn sold for ARS830 a ton, while March 2013 futures contracts changed hands at $180 a ton.
Earlier Thursday, the Buenos Aires Cereals Exchange provided its first estimate of Argentina's 2012-13 commercial corn crop, pegging output at a record 25 million metric tons, up from the 21.5 million tons grown during last year's drought-ravaged season. Planting is done.
The exchange's forecast is significantly lower than the USDA, which forecast Argentina's 2012-13 corn crop at 27 million tons.
Argentina is the world's No. 3 global corn exporter behind the U.S. and Brazil and worries over the dry weather in Argentina have helped support international prices due to tight stocks after the drought in the U.S. last season.
However, global corn prices eased over the past week, in part due to a slight improvement in weather conditions in Argentina.
While scattered showers provided some relief to fields in Santa Fe, Cordoba, Buenos Aires and Santiago del Estero province over the past week, across much of the farm belt, the corn and soybean crops are still suffering from dry soil and sweltering heat, said Buenos Aires Cereals Exchange chief agricultural analyst Esteban Copati.
Unless significant showers soak those fields soon, "we'll keep seeing declining yields across extensive areas, affecting forecasts for production this season," Mr. Copati said.
Cooler temperatures and heavy showers are expected in the far north over the next week, but Argentina's central farm belt is in for another dry week, except for some isolated sprinkles, according to the Buenos Aires exchange.
Spot wheat sold for $220, compared with $260 last week.
