Corn steadies after hitting one-week low, soybeans edge higher
Soybean prices edged higher, drawing support from continued concern about potential harvest disruption in Argentina after rain at the weekend.
However, US and Brazilian government forecasts on Tuesday could put the focus back on bumper South American crops.
"The USDA and Conab both release updated crop forecasts tomorrow," said Tobin Gorey, director of agricultural strategy at Commonwealth Bank of Australia, referring to the US Department of Agriculture and Brazil's food supply agency.
"Analysts expect to see the Brazilian (corn) crop get bumped up into the 92.5-93.5 million tonne range, given growing conditions have been so favourable."
The most active Chicago Board of Trade (CBOT) corn contract was up 0.3 percent at $3.60-1/2 a bushel by 1145 GMT. In the previous session prices hit their weakest since March 31 at $3.57-1/4.
Soybeans rose 0.5 percent to $9.47 a bushel, having closed little changed on Friday.
The USDA is scheduled to release its monthly supply-demand report on Tuesday, with analysts surveyed by Reuters expecting the government to raise its estimates of corn and soybean crops in the Southern Hemisphere.
"Operators are staying careful ... before the USDA report," consultancy Agritel said in a note. "Corn and soybean production on the South American continent will surely be revised up from last month's report."
Argentina's 2016/17 soy harvest accelerated in the past week but concerns over heavy rain at the weekend lent some support.
Corn and soybeans were also underpinned by rising crude oil prices, which make crop-based biofuels more attractive.
CBOT wheat was up 0.1 percent at $4.24-1/2 a bushel, tracking the trend in corn.
Traders will be looking at a weekly USDA crop progress report after markets close on Monday for a first indication of corn planting and an update on wheat growing conditions.
Large speculators trimmed their net short position in CBOT corn futures in the week to April 4, regulatory data released on Friday showed.
The Commodity Futures Trading Commission's weekly commitments of traders report also showed that non-commercial traders -- a category that includes hedge funds -- increased their net short position in CBOT wheat and switched to a net short position in soybeans.