papilla: nipple-like projection; used to describe the tip of some sporangia and the localized wall thickenings on the inner surface of plant cell walls at sites penetrated by fungi (papillate sporangium of Phytophthora cactorum)
Plasmopara viticola (Downy Mildew) and Uncinula necator (Powdery Mildew) on Vitis vinifera leaves
zoosporangium: sporangium, or spore case, that bears zoospores (Phytophthora gonapodyides)
oospore: thick-walled, sexually-derived resting spore of Oomycetes (Phytophthora cinnamomi)
oogonium (pl. oogonia): female gametangium of Oomycetes, containing one or more gametes (Phytophthora cinnamomi)
Plasmopara viticola Disease Cycle
Downy mildew (Plasmopara viticola) shown on the upper and lower surface of a grape leaf.