Journal of Pest Science (2018) 91:799–813
Increasing entomopathogenic nematode biodiversity reduces ecacy
against the Caribbean fruit y Anastrepha suspensa: interaction
with the parasitoid Diachasmimorpha longicaudata
William K. Heve
· Fahiem E. El‑Borai
· Daniel Carrillo
· Larry W. Duncan
Received: 17 August 2017 / Revised: 22 November 2017 / Accepted: 1 December 2017 / Published online: 8 December 2017
© Springer-Verlag GmbH Germany, part of Springer Nature 2017
Entomopathogenic nematode (EPN) species richness merits studies towards making rational decisions for eﬀective manage-
ment of Caribﬂy, Anastrepha suspensa (Loew) in southern Florida. Competition for Caribﬂy and eﬃcacies of EPN biodi-
versity were examined under laboratory conditions. Similar EPN species treatments to Caribﬂy-infested fruits, periodically
obtained from the ground in groves which were also infested by the parasitoid Diachasmimorpha longicaudata Ashmead
(Braconidae), were studied in a series of ﬁeld trials. Treatments with individual EPN species and their mixtures caused
similar mortalities of Caribﬂy larvae, though the various EPN species competed for larvae in multiple-species treatments.
Laboratory trials showed that mortalities of EPN-treated Caribﬂy pupae were mostly inversely related to EPN diversity. In
the ﬁeld, population densities of emerging adult Caribﬂy increased with increasing number of EPN species combined in
treatments. Thus, single-EPN species treatments proved to be more eﬀective for the management of fruit-to-soil stages of
Caribﬂy. Relative to controls, the proportions of surviving adult Caribﬂy observed in EPN treatments with Heterorhabditis
bacteriophora (exotic in Florida), Steinernema feltiae (exotic EPN) and Heterorhabditis indica (the endemic species) in ﬁeld
plots were 22.5 ± 6, 45 ± 13 and 47 ± 13%, respectively. Number of emerging D. longicaudata in each of EPN species treat-
ments was similar to that observed in control, suggesting that none of the EPN species signiﬁcantly aﬀected the emergence
of D. longicaudata, a parasitoid of Caribﬂy. Heterorhabditis bacteriophora will be more promising, with insigniﬁcant side
eﬀects on D. longicaudata in Caribﬂy-integrated pest management.
Keywords Entomopathogenic nematode species richness · Heterorhabditis bacteriophora · Steinernema feltiae ·
Heterorhabditis indica · Antagonistic eﬀects · Psidium guajava
The use of entomopathogenic nematode (EPN) species
richness to manage Caribﬂy in south Florida, where the
parasitoid Diachasmimorpha longicaudata is endemic,
has not been investigated.
In both laboratory and ﬁeld trials, single-EPN species
treatments were more eﬃcacious than their multiple-
In the ﬁeld, no EPN treatments signiﬁcantly reduced den-
sities of D. longicaudata, a parasitoid of Caribﬂy.
Heterorhabditis bacteriophora was more eﬀective than
Heterorhabditis indica or Steinernema feltiae in the ﬁeld
and will be more useful in Caribﬂy IPM.
Communicated by M. Traugott.
* Larry W. Duncan
Citrus Research and Education Centre, Institute of Food
and Agricultural Sciences, University of Florida, 700
Experiment Station Road, Lake Alfred, FL 33850, USA
Department of Plant Protection, Faculty of Agriculture,
Zagazig University, Zagazig, Egypt
Tropical Research and Education Centre, Institute of Food
and Agricultural Sciences, University of Florida, 18905 SW
280th Street, Homestead, FL 33031, USA