Iowa, USA, 15 June 2007: Researchers in Iowa State University, have developed a way to use satellite images to find Asian soybean rust. Using remote sensing, GIS and GPS, scientists can measure the green leaf area of soybeans to detect and identify diseases down to the area of a square meter, about 1.2 square yards.
“Plant pathogens and pests impact the green leaf area index of crop canopies in different ways and those changes can be detected and quantified using remote sensing,” said Forrest Nutter, professor of plant pathology.
The footprints of early soybean rust infection are oval-shaped. The way it spreads over time in a field helps identify it from other diseases.
Nutter envisions the technology being used to narrow the search for soybean rust or other diseases. Plant disease detection using satellites would provide the GPS coordinates for spotters on the ground to pinpoint locations to collect disease diagnoses field samples. The samples would then be taken in for laboratory tests to confirm the identity of the plant disease at that location.
Tests conducted last year in South Africa demonstrated the technology. Nutter has been working on the project with plant pathologist Neil van Rij of Cedara, South Africa; John Basart, Iowa State Engineering Professor; and Khalil Ahmad, engineering graduate student.
Nutter said the USDA and Department of Homeland Security are interested in using the technology to alert officials to a soybean rust infection during the crop season. Being able to monitor the movement of soybean rust could help reduce the impact of the devastating disease.
Soybean rust, also known as Asian soybean rust, is a disease that affects soybeans and other legumes. It is caused by two types of fungi, Phakopsora pachyrhizi and Phakopsora meibomiae. P. meibomiae is the weaker pathogen of the two and generally does not cause widespread problems. The disease has been reported across Asia, Australia, Africa, South America and the United States.
In response to the recent introduction of soybean rust into the US, United States Department of Agriculture (USDA) facilitated the development of a federal, state, university and industry-coordinated framework for surveillance, reporting, prediction, and management of soybean rust.