VIEW ARTICLE

Ecology and Epidemiology

Feeding Behavior of Criconemella xenoplax in Monoxenic Cultures. S. W. Westcott III, Visiting assistant professor, Department of Plant Pathology and Physiology, 120 Long Hall, Clemson University, Clemson, SC 29634-0377; R. S. Hussey, Professor, Department of Plant Pathology, University of Georgia, Athens 30602. Phytopathology 82:936-940. Accepted for publication 27 May 1992. Copyright 1992 The American Phytopathological Society. DOI: 10.1094/Phyto-82-936.

Criconemella xenoplax was grown in monoxenic cultures on crimson clover, carnation, tomato, and western sand cherry. Nematode population densities increased on crimson clover, and second-stage juveniles did not accumulate in cultures. Some second-stage juveniles did not feed or develop further on carnation and tomato, resulting in accumulation of this stage in cultures. All stages of the nematode fed on the western sand cherry, but roots remained viable for only 4–5 wk. Feeding behavior was studied in most detail on tomato, but it appeared to be similar on all hosts. Stylet penetration of root tissue was deliberate and lasted up to 80 min. After penetration, the stylet became stationary and a 1- to 3-h secretion phase followed. Secretion was accomplished by intermittent twitching of the posterior of the metacorpus and apparent slight opening of the pump chamber. Globular secretions accumulated around the stylet tip in parasitized cells. Ingestion was characterized by maximum dilation of the pump chamber and was continuous for up to 8 days. Ingestion ceased and the stylet was retracted when adults became gravid. Juveniles often molted after a single feeding episode. C. xenoplax fed as an ectoparasite for prolonged periods on a single-root cortical cell without destroying the cell.