The Potential Use of Entomopathogenic Nematodes to Control Planococcus ficus (Signoret) (Hemiptera: Pseudococcidae)

  • P.D. le Vieux Department of Conservation Ecology and Entomology, Stellenbosch University, Stellenbosch, South Africa
  • A.P. Malan Department of Conservation Ecology and Entomology, Stellenbosch University, Stellenbosch, South Africa

Abstract

Laboratory bioassays were conducted to establish the potential of entomopathogenic nematodes (EPNs) as
biocontrol agents of Planococcus ficus (Signoret). Six indigenous and two commercially available nematode
species were screened for their efficacy in killing adult female P. ficus. The two indigenous species with
the most promising results were Heterorhabditis zealandica and Steinernema yirgalemense, which were
responsible for 96% and 65% mortality respectively. Tests were conducted to compare the efficacy of
H. bacteriophora and S. feltiae produced in vivo and in vitro. Heterorhabditis bacteriophora showed no
significant difference in efficacy between the two production methods, but in vivo-cultured S. feltiae
produced a significantly higher mean mortality of 40%, in contrast to a 19% mean mortality with in vitroproduced
infective juveniles (IJs). The capability of both H. zealandica and S. yirgalemense to complete
their life cycles in the host and to produce a new cohort of IJs was demonstrated. Bioassays indicated
a concentration-dependent susceptibility of P. ficus to H. zealandica, S. yirgalemense and commercially
produced H. bacteriophora, with LC50 and LC90 values of 19, 82; 13, 80; and 36, 555 respectively. Both H.
zealandica and S. yirgalemense were able to move 15 cm vertically downward and infect P. ficus with a
respective mortality of 82% and 95%. This study showed P. ficus to be a suitable host for H. zealandica
and S. yirgalemense, with both nematode species showing considerable potential for future use in the field
control of P. ficus.
Published
2013-08-23
Section
Articles