Hatching of the root-lesion nematode, Pratylenchus penetrans, under the influence of temperature and host

Abstract

Abstract The influence of temperature and root diffusates from different plants on the hatching behaviour of Pratylenchus penetrans was studied. Diffusates were obtained from maize (cv. Husar), carrot (cv. Masei), black salsify (cv. Omega), pea (cv. Alouette), bean (cv. Polder) and marigold (cv. Single Gold) at different plant ages. Soil leachate was used as a control treatment. Hatching was also examined in 10% dilutions of the root diffusates and the soil leachate. Hatching was monitored at 5-day intervals until 60 days at most. Test solutions were refreshed at the same intervals. Pratylenchus penetrans hatched more at 20°C than at 10, 15 or 25°C. Hatching was stimulated by all host diffusates, as well as marigold; it was highest in maize and bean diffusates (ca 50%). Except for carrot diffusate and soil leachate, hatching activity decreased with increasing plant age. It also decreased in 10% diluted root diffusates, except for pea, black salsify and soil leachate. There was no evidence for the presence of hatching inhibitors in the diffusate of any host.