PRINCETON, Ky. — On Aug. 8, after 10 years of testing, a USDA weekly report known as the Soybean Rust Commentary said for 2014 there has been little incidence of the soybean rust (SBR) disease active on the North American continent.
The report, which farmers and other interested parties can access anytime, can be viewed online at http://sbr.ipmpipe.org/cgi-bin/sbr/public.cgi
Last week, it read in part: "SBR was reported on kudzu in Gadsden, Taylor and Lafayette counties in Florida on Aug. 4. SBR has now been detected in 11 counties in central and north-central Florida."
Further, "SBR was detected in a soybean sentinel plot in Autauga County in Alabama on Aug. 3. This is the first report of SBR on soybeans in the U.S. during the current growing season. The disease has also been observed on kudzu in southern Louisiana."
Basically, what that means is within the entire United States with the growing season approaching a close, SBR disease has been detected in only one soybean field. (Incidentally, it had been feared in the early days of 2004 that SBR would overwinter in kudzu plants and then move rapidly to the soybean crop in the spring.)
Soybean rust is a yield-robbing disease spread by windborne spores coming up from the South. Before the disease reached the United States there were reports of yield losses of up to 100 percent in some South American countries. It is believed the disease came from Venezuela to the United States by the winds of Hurricane Ivan in 2004.
From 2005-10 University of Kentucky extension plant pathologist Don Hershman was co-director of a national organization aggressively combating the spread of soybean rust into the United States. In the beginning of his tenure, rust was considered to have the potential to destroy the entire U.S. soybean crop.
It was in 2004 he became part of a group of plant pathologists from more than 30 U.S. land-grant universities who joined with organizations like the USDA, the United Soybean Board (USB) and other industry groups and entrepreneurial IT experts. The pathologists’ role in the new campaign was to study the threat and minimize the effects of rust on the U.S. crop.
The mixed-organizational program eventually became known as the Integrated Pest Management Pest Information Platform for Extension and Education (IPM PIPE). The result was the implementation of an integrated national system using information technology to coordinate IPM data and management techniques.
A well-managed collaboration among the scientists and all of the other agencies involved resulted in a network of soybean plots being planted across the United States in order to monitor for existence of rust, to develop educational materials, to test and register fungicides and to conduct soybean variety trials for disease-resistant traits.
Today, Hershman gives credit to USDA’s Animal and Plant Health Inspection Service for supplying a coordinated framework and ample resources to develop a program that is centered on a single website where IPM PIPE components could upload and monitor data from a vast sentinel plot network, and U.S. farmers could get up-to-date information.
In 2005, when little was known about soybean rust Kentucky had 42 different sentinel plots. As time went on it became obvious when the spores reached up into Kentucky the soybean crop had already advanced to a stage where the disease had no effect on yield.
In late 2013, Hershman said, "Based on limited SBR activity in the mid-South to date ... We will not be showered with SBR spores until early/mid September." That would be too late for the disease to do much damage to the crop in Kentucky, he noted.
More recently he said soybean rust is not going to show up suddenly in the state of Kentucky and do a lot of damage. Instead, if ever it does come it will creep north slowly from the South, which is still being monitored weekly, and an alert will be sent to county agents and farmers in time enough to respond.