Presented at the Fourth Annual Statewide CSTEP Conference, November 1995
DANIEL ESCALERA, THE EFFECT OF HOST STATUS ON VIRULENCE IN POTATO CYST NEMATODES., EDWARD J. CATAPANE, MEDGAR EVERS COLLEGE AND BILL B. BRODIE, CORNELL UNIVERSITY, SPONSORS.
When both resistant and susceptible plants are inoculated with equal numbers of potato cyst nematodes, significantly higher numbers of nematodes egress from the resistant plants than the susceptible plants. Recent studies have shown that there are certain chemicals which are in higher concentrations in these resistant plants than in susceptible plants. These chemicals called phytoalexins were tested to determine if they had any repellent effects on the nematode and to see if they were responsible for egression. Our attempts to demonstrate direct stimulatory effects of these phytoalexins on the nematodes were unsuccessful in our in vitro studies. Our in vivo studies using plants with varying concentrations of solavitevone , a phytoalexin found in higher concentrations in resistant plants that in susceptible plants, also failed to demonstrate any stimulatory effect on the Golden nematode. Although only preliminary, the data suggests that these phytoalexins are not individually responsible for the egression of second stage juveniles from resistant potato roots.
This project was supported in part by grant 0516-95-0063 from the New York Education Department and by the NSF and Cornell Environmental Science Undergraduate Research Experience (CESURE) Program.