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July 18, 2011

Producers in Parana Want to Plant Soybeans Earlier

Soybean producers in Parana are petitioning the Brazilian Minister of Agriculture to adjust the official planting date of soybeans in the state so that they can plant their soybeans at least 10 days earlier than currently permitted. Over the last several years, the Brazilian government has developed a system of zoning for the various agricultural crops grown in the country. This system includes where certain crops may be grown and the planting windows for the crops. In order to qualify for government programs, producers must conform to the zoning regulations for their region.

The reason why they are requesting the change is to avoid a repeat of the devastating frost/freezes that disseminated their safrinha corn crop at the end of June. They feel that if they can plant their soybeans earlier then they can plant their safrinha corn earlier as well and potentially have the corn crop mature before potential cold weather hits again next June.

Over the last five years, soybean producers in western and northern Parana have been moving toward more early and semi-early soybean varieties that mature in 90-100 days. If these early varieties are planted at the end of September, they can then be harvested at the end of January or early February thus allowing more time for the safrinha corn crop to mature.

Early or semi-early maturing soybeans in southern Brazil generally can yield just as well as later maturing soybeans due to their reproductive cycle. These early maturing soybeans are generally indeterminate which means they flower and grow at the same time (similar to the soybeans grown in the majority of the U.S.). If conditions are poor during part of their flowering period due to excess rainfall or a lack of rainfall, the plants can set new flowers later when conditions are more favorable. The later maturing soybeans grown in the state are determinates which means that they grow first and then flower all at one time. If conditions are poor during the flowering period of determinate soybeans, then the plant does not have another chance to set additional flowers.

A majority of the soybeans grown in the state of Parana are already indeterminate varieties. During the 2006/07 growing season, of the 11 soybean varieties grown over 80% of the state, only one variety was indeterminate. During the 2010/11 growing season, of the 14 varieties grown over 80% of the state, 9 were indeterminate.

In parts of western Parana, the cold temperatures were so severe at the end of June that up to 40% of the safrinha corn crop was lost. Researchers estimate that if early or semi-early soybean varieties had been planted 10 days earlier than currently allowed, the losses to the safrinha corn would had been no more than10%.