International Journal of Horticulture 2015, Vol. 5, No.16, 1-6
1
Research Report
Open Access
Lethal and Parasitism Effects of Fipronil on
Trichogramma chilonis
(Ishii)
(Hymenoptera: Trichogrammatidae)
Muhammad Ashraf Khan , Adnan Khan
Department of Environmental Sciences, University of Peshawar, Pakistan
Corresponding author email
International Journal of Horticulture, 2015, Vol.5, No.16 doi: 10.5376/ijh.2015.05.0016
Received: 29 Aug., 2015
Accepted: 10 Sep., 2015
Published: 14 Dec., 2015
Copyright
© 2015 Khan and Khan., This is an open access article published under the terms of the Creative Commons Attribution License, which permits
unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Preferred citation for this article
:
Khan M.A., and Khan A., 2015, Lethal and parasitism effects of fipronil on
Trichogramma chilonis
(Ishii) (Hymenoptera: Trichogrammatidae), International
Journal of Horticulture, 2015, Vol.5, No.16 1-6 (doi
Abstract
The effects of lower doses including 0.4x, 0.2x, 0.08x, 0.04x, and 0.02x field recommended dose (x) of insecticide fipronil on the
emergence of
Trichogramma chilonis
(Ishii) from the treated larval and pupal stages of parasitoid within the host eggs of
Sitotroga cerealella
Olivier, and parasitism of the previously treated host eggs (
S. cerealella
) by females T.
chilonis
were assessed under laboratory conditions. Both
0.4x and 0.2x doses of fipronil led to complete failure of emergence, while the remaining three doses demonstrated ≤ 25.61% emergence in the
larval treatment. However, pupal treatment indicated comparatively less toxicity to the parasitoids, i.e., the 0.4x dose showed 3.40%, while 0.2x
and 0.08% doses revealed emergence 29.05 and 39.65%, respectively. The lowermost doses including 0.04x and 0.02x showed emergence 61.81
and 73.51%, respectively when host eggs were treated at pupal stage of parasitoid. Fipronil also affected parasitism of the previously treated host
eggs of
S. cerealella
, and led to increase in parasitism capacity when dose shifted from high rate toward lower rate: demonstrated increase in
mean parasitism ranging from 5 to 10.7.
Keywords
Fipronil; Treatment; Parasitism; Emergence;
Sitotroga cerealella
; Olivie
1 Introduction
Egg parasitoids effectively manage a number of crop
pests (Moura et al., 2006), and thus regulate natural
populations of other insects (Delpuech and Delahaye,
2013). The parasitic wasps belonging to the genus
Trichogramma
are widely distributed and perform key
role in the control of the pests belonging to the order
Lepidoptera on a wide range of agro-ecosystem
(Hassan and Abdelgader, 2001). Pesticides use
adversely affects the beneficial performance of
Trichogramma
(King et al., 1986; Khan et al., 2015b).
Therefore, it is required to evaluate pesticides adverse
impacts on
Trichogramma
to effectively integrate
both chemical and biological controls (Khan et al.,
2015a).
Trichogramma chilonis
(Ishii) have wide distribution
throughout the Indian subcontinent and has been used
to effectively control caterpillar pests in various
agro-ecosystems (Manjunath et al., 1985; Khan et al.,
2014). They control pests including
Chilo
spp. in
sugarcane, maize, and
Helicoverpa armigera
in cotton,
tomato, and lady’s finger in India (Singh, 2001). It is
an important egg parasitoid of lepidopteran pests in
Pakistan (Sattar et al., 2011; Khan et al., 2014), and
control pests including sugarcaneborer (
Chilo
sacchariphagus
) in sugar cane, diamondback moth
(
Plutella xylostella
) in cabbage and other vegetables,
and cotton bollworms (
Helicoverpa armigera
) in
cotton and corn (Rasool et al., 2002), and rice leaf
folder
Canphalocrocis medinalis
(Guenée)
(Sagheer et al., 2008) in Pakistan
.
The current study aimed to evaluate the adverse
effects of lower doses of fipronil (≤ 0.4x while “x”
show field dose) in the field on the larval and pupal
mortalities of
T. chilonis
within the host eggs
(
Sitotroga cerealella
), and effectson parasitism of
previously treated eggs of
Sitotroga cerealella
by the
minute parasitoid in order to determine the rate of the
chemical most compatible with
T. chilonis
.
2 Materials and Methods
2.1 Rearing of
Sitotroga cerealella
olivier on wheat
grain
Eggs of grain moth
S. cerealella
were sprinkled on the
wheat grain in metal/plastic tray (20x30 cm), and the
young larvae hatched within 4-6 days. The infested
