Characterisation of Pythium paroecandrum and its antagonism towards Botrytis cinerea, the causative agent of grey mould disease of grape.

Pythium paroecandrum (B-30), an oomycete, was isolated from soil samples taken from a wheat field in Genlis in the Burgundy region of France and was found to check the growth and development of Botrytis cinerea, a serious grapevine pathogen. The oomycete is a fast-growing organism, living on vegetable debris, and can be recognised by its catenulate hyphal swellings, catenulate oogonia, and monoclinous antheridia. When grown together with B. cinerea, the causal agent of the grey mould disease of the grapevine, P. paroecandrum shows a pronounced antagonism and suppresses its growth and its aptitude to provoke the grey mould symptoms. Morphological features of this oomycete, its antagonism to …