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

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.

Distribution of parasitic nematodes in Kenyan rice fields and their relation to edaphic factors, rainfall and temperature

“…The same temperature provides optimum conditions for hatching and oviposition in Aphelenchoides besseyi (Huang et al 1972). Hatching (Pudasaini et al 2008) and vertical migration (Pudasaini et al 2007) of root lesion nematode Pratylenchus is also influenced by temperature. Vertical migration of A. besseyi increases with increasing relative humidity at 25-30°C (Sun et al 2009).…”

The dual effects of root-cap exudates on nematodes: from quiescence in plant-parasitic nematodes to frenzy in entomopathogenic nematodes

“…In addition to attracting nematodes, root exudates also trigger egg hatching in certain plant-parasitic nematode species (e.g. Perry and Clarke, 1981 ; Dennijs and Lock, 1992 ; Perry and Gaur, 1996 ; Gaur et al , 2000 ; Wesemael et al , 2006 ; Pudasaini et al , 2008 ; Khokon et al , 2009 ; Oka and Mizukubo, 2009 ). Yet root exudates can also protect roots against plant-parasitic nematodes.…”

A multiplex real-time PCR assay for the simultaneous quantification of the major plant-parasitic nematodes in Japan

“…Large differences in the density of M. incognita estimated by the Baermann and real-time PCR methods were already reported by Min et al (2011) and it was discussed that eggs or dormant forms of M. incognita may be detected only by the real-time PCR assay. Juveniles of P. penetrans need 20-30 days for hatching (Pudasaini et al, 2008) and more than 50% of second-stage juveniles of M. incognita did not hatch in distilled water within 72 h (Oka & Mizukubo, 2009). These results suggest that most eggs of P. penetrans and M. incognita are not counted after 2-3 days of incubation in the Baermann method, but counted by the real-time PCR assay.…”