ART4 and cyst: Immunolabelling studies using a monoclonal antibody, Lpv-1, directed towards the high molecular weight glycoprotein, PcLpv, stored in the large peripheral vesicles in P. cinnamomi zoospores indicated that large peripheral vesicles do not undergo exocytosis during zoospore encystment but instead became dispersed throughout the cyst cytoplasm (Gubler & Hardham, 1988).