Dead or alive? A new test to determine viability of soybean rust spores

Seed Daily via SPX: Spores from Asian soybean rust (Phakopsora pachyrhizi) pose a serious threat to soybean production in the United States because they can be blown great distances by the wind. University of Illinois researchers have developed a method to determine whether these spores are viable.

"Finding spores is different from finding spores that are living and able to infect plants," said USDA Agricultural Research Service (ARS) scientist and crop sciences professor Glen Hartman.

Soybean rust, which first appeared in Japan at the beginning of the 20th century, is a foliar infector that reduces plant photosynthetic activity and causes defoliation, premature death, and high yield loss. An obligate pathogen, it grows only on plants and dies when the plant dies or is harvested.

The fungus first appeared In the U.S. in 2004. It is concentrated in the southern states where it is able to overwinter on kudzu. Spraying with fungicides is the only way to control it because resistant soybean cultivars are not yet available to U.S. farmers....

A photo of soybean rust from the US Department of Agriculture