First report of Pythium deliense associated with peanut pod rot in Georgia.
In autumn 2012 and 2013, groundnut (Arachis hypogaea) grown in commercial fields in Tift County (Geaorgia, USA), showed pod rot symptoms. The disease was primarily damaging pods and kernels and symptoms included brown to black, water-soaked lesions on pods and blackened pegs with white fluffy mycelia. Based on growth pattern and sporangial and oogonial structures, sequence analysis of the rDNA internal transcribed spacer (ITS1-5.8S-ITS2) regions, and pathogenicity tests, three pathogens were identified: P. ultimum, P. vexans and P. deliense. P. ultimum and P. vexans have been reported to be associated with groundnut pod rot in the United States. This is thought to be the first report of P. deliense causing groundnut pod rot.