SAMPLING BIOAEROSOLS IN PLANT PATHOLOGY

Bioaerosols of interest in plant pathology are comprised principally o f the air-borne or splash-borne fungal spores or bacterial cells which disperse many plant diseases. Plant pathogen inoculum is mostly sampl ed out of doors, imposing environmental constraints on sampling method s arising for the need to sample in fluctuating winds and to protect s amples from rain. The choice or method of sampling can be affected by biological considerations, such as when and where inoculum is released and the size and shape of the propagules. These considerations are di scussed in relation to choice of sampling methods for use in plant pat hology studies. Passive deposition samplers, bait plants and volumetri c samplers (suction and rotating-arm) are described and their advantag es and disadvantages are discussed. Current samplers rely almost exclu sively on optical microscopy or culture methods for identifying and en umerating air-borne plant patho en inoculum. Recently, developed immun ological techniques for the detection of air-borne plant pathogens are briefly considered. (C) 1997 Elsevier Science Ltd.