August 16, 2005
From: ProMED-mail <promed@promedmail.org>
Source: StopSoybeanRust.com, 15 Aug 2005 [edited] <http://www.stopsoybeanrust.com/viewStory.asp?StoryID=504>

First Asian soybean rust found in South Carolina commercial field - furthest north yet

Asian soybean rust [ASR] has been confirmed in the southern part of South Carolina in a Hampton County commercial soybean field. This is the 1st confirmed ASR outbreak in the state and becomes the northern-most county infected with ASR in the country, just north of Effingham County across the border in Georgia.

Hampton County extension agent Tommy Walker collected the sample last week [2nd week August 2005], and it was allowed to incubate before being examined on Saturday [13 Aug 2005]. John Mueller, Extension soybean
pathologist with Clemson University, pegged it as ASR and sent it to the Plant Problem Clinic for confirmation early Monday morning [15 Aug 2005].

In Mueller's commentary [edited], he said ASR in the Hampton County field is at a low level and is doing very little damage to that field, while also not producing enough spores to immediately threaten nearby fields.

"However, it is evident that ASR spores, most likely from Georgia or Florida, are being deposited in South Carolina fields," Mueller said.

South Carolina state commentary, 15 Aug 2005:

Observations:
15 Aug 2005: ASR was confirmed today in a sample collected last week [2nd week August 2005] from a commercial soybean field (R3/4) in Hampton County, SC by Tommy Walker, Hampton County Agricultural Agent. A 2nd sample from a commercial field (R4) in Dorchester County, collected by County Agricultural Agents Joe Varn and Marion Barnes, strongly resembled the pustules from the Hampton County site; however, positive identification was not possible at this time, since sporulation was not observed. Further analysis is being performed.

11 other fields in the Lower Savannah Valley were collected and examined last week [2nd week August 2005]. 2 of these fields were within 100 yards of the affected field in Hampton County. No sign of rust was detected in
any of those fields. 30 leaves were examined from each of the fields. Only one ASR-infected soybean leaf was found from either of the fields. Less than 5 pustules were observed on either leaf.

Growth Stages:
Much of the full-season soybean crop in South Carolina is past flowering, and pods are developing rapidly. Early planted maturity group 3 and 4 soybeans are near maturity. Soybeans planted behind wheat are still at the
vegetative stage.

Disease Management:
Many growers in the Lower Savannah River Valley have recently sprayed protecting fungicides for control of leaf, stem, and pod diseases. They should wait until their spray interval has expired, or rust in neighboring fields becomes severe, to apply a 2nd spray. Application of a 2nd spray will be dependent upon the development of ASR in surrounding fields. At the low level of ASR detected in Hampton County, it should be at least 10 to 14 days before ASR could develop to a stage where damage is likely. Growers north of Santee and West of Barnwell County should continue to spray beans with high yield potentials as needed for leaf, stem and pod diseases. It should be 10 to 14 days before they need to start focusing their sprays on ASR.

--
ProMED-mail
<promed@promedmail.org>

[ASR is slowly spreading but should start tapering off in the next week or so. The most recent infection marks the furthest north that ASR has been reported, and we can only wait to see how it plays out. Dr. Chris Hurt, Agricultural Economist at Purdue, said that after 20 Aug 2005, growers will not need to worry about ASR, because even if ASR did show late in August 2005, it would take nearly 2 weeks to develop to the point of defoliating plants. Asked to make a prediction for next year (2006), Hurt thinks that many growers will have invested in costly fungicides to such an extent that many will be less inclined to make substantial investments in fungicides in the future.

Link:
<http://www.brownfieldnetwork.com/gestalt/go.cfm?objectid=C111A236-EE14-2289-DED722F8E77BB9AA>
- Mod.DH]

[see also in the archive:
Soybean rust, Asian strain - USA (FL): 1st report 2005 20050309.0693 Soybean rust, Asian strain - USA (GA) 20050429.1196 Soybean rust, Asian strain - USA (GA) 20050505.1245 Soybean rust, Asian strain - USA (LA) 20050624.1769 Soybean rust, Asian strain - USA (FL) (02) 20050620.1731 Asian soybean rust, Asian strain - USA (multistate) 20050724.2133 Soybean rust, Asian strain - USA (AL) 20050715.2029 Soybean rust, Asian strain - USA (multistate)(03) 20050714.2005 Soybean rust, Asian strain - USA (multistate)(02): Florida 20050708.1938 Soybean rust, Asian strain - USA (multistate) 20050702.1868 Soybean rust, Asian strain - USA (FL)(03) 20050815.2386 Soybean rust, Asian strain - USA (Multistate)(06) 20050808.2318 Soybean rust, Asian strain - USA (multistate)(05): susp. 20050806.2291 Soybean rust - USA (multistate)(04) 20050806.2289]