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July 24, 2013

Cold Temps in Brazil could Impact Wheat and Slow Corn Harvest

A mass of polar air sweeping into southern Brazil is expected to bring widespread freezing temperatures to areas of Rio Grande do Sul, Parana, Mato Grosso do Sul and as far north as Sao Paulo. There is also the possibility of light snowfall in the region as well.

The crop that could be impacted the most from the frigid temperatures is the winter wheat crop in Parana and Rio Grande do Sul. The most advanced wheat in Parana is in the jointing stage while the wheat in Rio Grande do Sul is still in the vegetative stage.

If wheat is in the jointing stage, damage from cold temperatures is only going to occur if temperatures fall to at least 28 degrees or lower for a minimum of 4 hours. Even then, the damage to the crop would not be catastrophic. Flowering and heading is the time when the wheat crop is most sensitive to freezing temperatures and none of the wheat in southern Brazil is at that stage of development.

Brazil is expected to produce approximately 5.1 million tons of wheat and import 7.2 million tons to meet domestic demand. Traditionally, Brazil imports its wheat from neighboring Argentina, but that is not going to be possible this year because of export restrictions on wheat that was imposed by the Argentine government for fear that the country may run out of wheat before the new crop is harvested in December.

Cold temperatures such as these are not good for the wheat, but wheat is a very hardy crop and losses from the cold weather will probably be in the moderate range. Any losses to the crop would force Brazil to source additional wheat supplies from outside of South America. It takes a number of days after the freezing temperatures before any accurate assessment of the damage can be calculated.

The cold temperatures and high humidity is disrupting the corn harvest in Mato Grosso do Sul where approximately 30% of the safrinha corn has been harvested. The corn harvest is most advanced in the northern part of the state is 40% of the corn has been harvested. In the southern part of the state only 27% of the corn has been harvested. While the cold temperatures will slow the harvest pace, the crop is mature enough that the cold temperatures are not expected in negatively impact the corn yield potential.

The statewide average corn yield in Mato Grosso do Sul is expected to be 100 sacks per hectare or 92 bu/ac. The highest yields in the state are expected in the western part of the state along the border with Paraguay where 110 sacks per hectare are expected (101 bu/ac).

The cold temperatures will not only impact the wheat crop, they could also impact the coffee and sugarcane crop in northern Parana and the state of Sao Paulo.