I’m grateful that at least some growers along the Coastal Plain of Georgia received rain this past weekend, a “million dollar rain” according to my friend and colleague Dr Camp Hand.  I hope so; I do know for peanut growers the rain will help to reduce the risk to Aspergillus crown rot.  This disease, favored by hot and dry early in the season, can result in significant stand loss and increased risk to tomato spotted wilt disease.

Included today are eye candy pictures sent to me by Jeremy, Rome, and Danny Bennett. My hope is that if you see these symptoms while you are in a peanut field, or when a grower brings you sample, you will have some idea what you are looking at.

The first two pictures this morning are of early planted peanuts in central Georgia. In the first two are leaves with a typical burn along the margins consistent with use of Thimet. (Such is also evident in pic 4 sent to me a year ago by Rome in Seminole Co). “Thimet burn” is cosmetic only and is “proof” that the product is at work in the plant reducing risk to tomato spotted wilt.

Pic 3 is from the same field as are pics 1 and 2. My concern here is that the stand appears “skippy” and “skippy stands”, especially so early in the season, really predispose the crop to tomato spotted wilt.

Skippy stands can occur for a number of reasons, but in my world of “plant diseases”, the reasons are most often seed rot (poor quality seed and/or ineffective seed treatment) and seedling diseases.

Next pic is from Jeremy in Colquitt Co and are examples of typical seedling diseases of peanut.  In pic 5 note the deep sunken lesions girdling the peanut stem just below the soil line. Such lesions are indications of Rhizoctonia seedling disease which is more common in wetter soils.  Azoxystrobin in-furrow helps with this. 

In pic note the dark sooty sporulation where the lower stem has been eaten away.  This is Aspergillus niger causing Aspergillus crown rot.  Trebuset and Rancona seed treatments help with this, as does the fluopyram found in Velum and Propulse. 

Finally, in this pic is both Aspergillus crown rot (note the dark sporulation) AND early season white mold developing (note the ropey white fungal growth along the taproot). While I do not recall the exact details as Jeremy sent this last year, the presence of both crown rot and white mold is indicative of warm soils. 

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