Weed hosts associated with Sclerotinia sclerotiorum
Sclerotinia sclerotiorum (Lib.) de Bary is capable of causing disease on over 500 plant species (Boland & Hall, 1994; Saharan & Mehta, 2007) of which some are weeds. In South Africa, confirmed weed hosts of S. sclerotiorum include the common blackjack (Bidens pilosa), common cosmos (Bidens formosum), pigweed (Amaranthus deflexus) and tall khakibos (Tagetes minuta; Phillips, 1992). These plants serve as alternative hosts, they are not required for the completion of the pathogens life-cycle. However, they do contribute to the persistence of the pathogen during the season and provide ‘shelter’ for the pathogen at the end of the growing season. Therefore, integrating weed management strategies into your production system will also serve as a manner in which to reduce the risk of diseases caused by S. sclerotiorum .
Author: Lisa Rothmann
Universtiy of the Free State UFS
Department of Plant Science, Plant Pathology