1 (1)

wide range of habitats including natural and agricultural
sites (Table 1). Steinernema anatoliense is reported for the
first in Jordan.
The highlands were the region with the most EPN-positive
sites. Within this region, oak woodlands had the highest
recovery of EPN. Steinernematids were more prevalent
that heterorhabditids. In one site, Bader (Amman), two
EPN species S. feltiae and S. carpocapsae were recovered.
Similarly, S. carpocapsae and H. bacteriophora were found
coexisting in the locality of Al-Balqa (Arida). Sampling in
the desert yielded only one EPN-positive sample (H. bacteriophora).
This nematode was recovered in a mixed grass
habitat. The Jordan Valley also yielded only 1 positive
sample that contained H. bacteriophora. This isolate was
found in a sandy loam beach habitat, associated to a palm
tree.
3.2. Soil characteristics of EPN-positive samples
Soil texture of EPN-positive samples in the Highlands
region varied from loamy to silt-clay-loam. Soils were
moderately alkaline, with pH ranging from 7.1 to 7.5. Soil
texture in the Jordan Valley and Desert samples was
loamy and sandy-loam, respectively. Soil samples in the
Jordan Valley were slightly alkaline (7.7), whereas the soil
in Desert region sample had a slightly acidic pH (6.7)
(Table 1).
4. Discussion
The present study recorded for the first time the occurrence
of indigenous EPN and their bacterial symbionts in
Jordan. Nematodes were recovered from all three geographic
regions sampled. In spite of the low recovery of
EPN, only 0.9% (10 of the 1080) of all samples taken, the
finding of one Heterorhabditis and three Steinernema species
clearly shows that EPN are present in Jordan and
may be considered for further research.
Oak and coniferous forest habitats yielded the greatest
diversity of EPN. Two of the oak forest sites sampled
yielded mixed population of EPN species. S. anatoliense
was originally isolated from natural pastures in East Anatolia,
Turkey. The current finding of this species in a mixed
coniferous forest expands the habitat range of this steinernematid.
These findings are in agreement with reports from
other surveys (Stock et al., 1999; Sturhan and Lišková,
1999; Stock and Gress, 2005), which also found the greatest
diversity of EPN in woodlands and forest habitats.
Several Heterorhabditis spp. and strains have also been
reported from neighboring regions with similar climatic
and geographic conditions (Glazer et al., 1991, 1993; Iraki
et al., 2000; Shamseldean et al., 1996). For example, H.
bacteriophora strains have been recovered from Israel (Glazer
et al., 1993) and Egypt (Shamseldean et al., 1996). .H.
indica isolates have also been isolated from Egypt (Sham-

S. Patricia Stock et al. / Journal of Invertebrate Pathology 98 (2008) 228–234 233
seldean et al., 1996). Heterorhabditis tayserae has also been
reported in Egypt (Glazer et al., 1996). Steinernematids
have also been recovered in Israel, Palestine, Emirate of
Oman and Egypt (Abbas et al., 2001; Ganguly and Singh,
2000; Sansour et al., 2003; Glazer et al., 1991; Shamseldean
et al., 1996).
Results from this study, indicate that Steinernema spp.
and/or strains are more dominant and diverse that Heterorhabditis
spp. These results may be in relation to our
sampling strategy, which considered desert and semi-desert
habitats as well as forest and agricultural areas. Moreover,
differences in nematode diversity and distribution are probably
related to differences in the distribution of suitable
insect hosts and to the species of nematode involved
(Bedding and Akhurst, 1986; Mráček and Bečvář, 2000).
Several of these indigenous EPN, particularly the ones
from desert and semi-desert habitats, may provide a more
suitable alternative for an inundative release approach
against a variety of native pests such as: Zeuzera pyrina
L. (Lepidoptera: Cossidae), Capnodis tenebrionis (L.)
(Coleoptera: Buprestidae), Rhynchophorus ferrugineus
(Oliv.) (Coleoptera: Curculionidae), Gryllotalpa gryllotalpa
(L.) (Orthoptera: Gryllotalpidae), and a number of unidentified
scarab beetle larvae (Coleoptera: Scarabaeidae),
among many other pests. Furthermore, consideration of
these native entomopathogens in biological control and/
or integrated pest management programs will contribute
to minimizing current excessive usage of chemical pesticides
in this country.
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