Cohn, E., Agricultural Research Organization, The Volcani Center, Bet Dagan, Israel

The histopathology of Rotylenchulus reniformis and R. macrodoratus was studied on different hosts by light microscopy. A multinucleate condition of some hypertrophied pericycle cells in the R. reniformis feeding zone in mint was observed, and some cell wall breakdown in this zone was observed in mint and upland cotton. Syncytium formation by R. macrodoratus in oak and soybean roots is described. In contrast to R. reniformis, plant cell response to R. macrodoratus was not restricted to the pericycle tissue. R. macrodoratus induced a single, large and well-defined syncytium, extending deep into the stele, and bordered by a thickened wall which clearly isolated it from normal tissues. © 1976, Brill. All rights reserved.