Stereological Study of Isolates of the Genus Phytomonas
Abstract
The cytoplasmic organelles of different isolates of the genus Phytomonas were comparatively analyzed in relation to their relative volume in the cell. Isolates from Euphorbia hyssopifolia, E. charadas and E. pinea, P. francai from Manihot esculenta, and P. davidi were employed. Data were obtained for mitochondria, lipid inclusions, glycosomes (a peroxisome - like organelle), multivesicular bodies, nucleus, kinetoplast, vacuoles, dense bodies and other inclusions. Lipid inclusions were more frequent in biphasic médium grown isolates, while glycosomes were more conspicuous in the E. charadas isolate. Kinetoplastic DNA was more diffuse in the E. pinea and E. charadas isolates. The mean cellular volume was measured in a ZBÍ Coulter-counter coupled to a channelizer; biphasic medium-grown cells were smaller than monophasic medium-grown ones. These observations, in association with others, previously reported, indícate that each isolate has unique characteristics and could be considered distinct species.