A simple in-vitro 'wet-plate' method for mass production of Phytophthora nicotianae zoospores and factors influencing zoospore production

A simple in-vitro 'wet-plate' method for mass-producing Phytophthora nicotianae zoospores at >= 1.0 x 10(6) zoospores/ml is described. Temperature critically affected zoospore production; 22 degrees C was optimum, while 36 degrees C was completely inhibitory. Zoospores being the most important propagule of P. nicotianae, temperature of recycled irrigation water may be manipulated to reduce diseases in irrigated nursery crops. (C) 2007 Elsevier B.V. All rights reserved.