Spraying For Soybean Rust

Soybean production in Brazil grew rapidly since 1960 with area expanding from 400,000 hectares to 22 million hectares. Brazil is a major soybean producer-62 million tons per year. In 2001, soybean rust was first detected in Brazil and by 2003 the pathogen had spread to the entire country with yield losses up to 75% in individual fields. If fungicides are not used, Brazil would lose about 50% of its soybean production annually.

“More than 50 different fungicidal products are currently labeled for managing soybean rust in Brazil, and many of these have been evaluated annually since 2003/2004 in a nationwide network of standardized, uniform field trials (UFTs) coordinated by Embrapa Soja, a research unit of the Brazilian Agricultural Research Corporation.

We present a meta-analytical synthesis of the results of 71 uniform fungicide trials containing 930 entries (specific fungicidal treatments) conducted in Brazil from 2003/2004 to 2006/2007. …on average, fungicide treatments… increased yield by 43.9%.

The results of this analysis showed that fungicidal control of soybean rust in Brazil is highly effective… (indicating a relative disease reduction of between 90 and 100% in response to treatment). …these comparisons show that, despite favorable environmental conditions for soybean rust epidemics in Brazil, the disease can be managed very effectively with modern fungicides.”

Authors: Scherm, H, et al.
Affiliation: Department of Plant Pathology, University of Georgia.
Title: Quantitative review of fungicide efficacy trials for managing soybean rust in Brazil.
Source: Crop Protection. 2009. 28:774-782.