TABLE CONTENTS

significantly from the fosthiazate treatments in terms of Pf/Pi in spite of the increased control
observed, particularly in 2006 (90% and 59% respectively), demonstrating that the biological
control agent was as effective as fosthiazate at reducing nematode multiplication. The
combined treatment did not provide any additional reduction in Pf/Pi but demonstrated that
P. chlamydosporia was compatible with fosthiazate. Over the different developmental stages
of the juveniles there was evidence of parasitisation of J5 females on the plant root by P.
chlamydosporia. Root colonization by P. chlamydosporia tended to be higher in the P.
chlamydosporia treatment due to increased levels of juvenile nematodes in roots. Results
from both experiments demonstrated the efficacy of P. chlamydosporia as a biological
control agent of potato cyst nematodes and indicate its potential for use as part of an
integrated pest management strategy.
In vitro Pasteuria spp. Endospores Rate of Germination and Infection on
Belonolaimus longicaudatus
Hewlett, T.E., S.T. Griswold, J.P. Waters & K.S. Smith
Pasteuria Bioscience Inc., 12085 Research Drive Suite 132, Alachua Florida 32643
The majority of earlier studies of rate of germination and infection of Pasteuria spp. on
nematodes involve Meloidogyne species. Spore-filled females produce relatively large
numbers of spores and the majority of the life stages can be easily extracted from roots. Also
the existence of a unicellular cell stage in the life cycle of Pasteuria was unknown until
recently. Ectoparasitic nematodes are much more difficult to study since they produce much
lower numbers of spores and must be extracted from the soil. The development of an artificial
growth media for Pasteuria spp. allows for detection of Pasteuria cells and other growth
structures present in the nematode body. Belonolaimus longicaudatus and the Pasteuria spp.
that parasitizes it were used in a study to determine the rate of germination and infection of in
vitro- grown Pasteuria spores. In vitro produced spores were attached with a centrifuge
technique. Approximately 200 spore-encumbered nematodes were placed in clean moist sand,
in small petri plates. Nematodes were extracted from plates at 1, 2, 3 and 7 days and crushed
in wells with growth medium. Plates were observed immediately and after 24 hrs and
presence of cells, mycelial balls, thalli and spores were recorded. Spore germination and cell
growth had begun by 24 hrs. Cells, mycelial balls and thalli were present by 48 hrs and
spores were present at the 7-day sample. Spore germination is much more rapid than
reported for P. penetrans parsitizing root-knot nematodes, but germination was determined
by the presence of mycelial balls. Sporulation also occurred at a much higher rate, within 7
days, as compared to about 20 days for root-knot nematode.
5 th International Congress of Nematology, 2008 295