Intl. J. of Molecular Zoology, 2013, Vol.3, No.4, 14
-
16
http://ijmz.sophiapublisher.com
14
Research Report Open Access
Effect of Pesticides on the Metamorphosis of Silkworm
Bombyx mori
Kumutha P.
1
,
Padmalatha C.
2
,
Chairman K.
3
,
Ranjit Singh A. J. A.
3
1
Department of Zoology, Govindammal Aditanar College for Women, Tiruchendur, Tamilnadu, India
2
Department of Zoology, M. V. M. Govt. Arts and Science College for Women, Dindugal, Tamilnadu, India
3
Department of Zoology, Sri Paramakalyani College, Alwarkuchi, Tirunelveli, Tamilnaudu, India
Corresponding authors email:
journalpublish2012@gmail.com
;
Authors
International Journal of Molecular Zoology, 2013, Vol.3, No.3 doi: 10.5376/ijmz.2013.03.0004
Received: 30 Jan., 2013
Accepted: 16 Feb., 2013
Published: 4 Mar., 2013
Copyright © 2013, Kumutha et al. 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:
Kumutha et al., 2013, Effect of Pesticides on the Metamorphosis of Silkworm
Bombyx mori
,
Intl. J. of Molecular Zoology, Vol.3, No.3, 14
-
16
(
doi: 10.5376/
ijmz.2013.03.0004)
Abstract
The silk worm
Bombyx mori
fed will the mulberry leaves sprayed with pesticides to control pests influenced with
development. L.C 50 doses for an organophospharous pesticide, Dichlorovos and plant based pesticide Neem oil was estimated and
the Neem pesticide was found to inhibit the developmental stages of
Bombyx mori
at a high level when compared to Dichlorovos.
The larval and pupal abnormalities noticed in pesticide treated worms which depend on the concentrations of the pesticides.
Keywords
Bombyx mori
;
Silk worm; Neem oil; Biopesticides; Dichlorovos
Introduction
Mulberry (
Morus
spp) is infested by several pests. The
insecticides applied for the control of mulberry pests
have greater impact on silkworm. Pesticides leave
residues in mulberry leaves which inturn affect the
sensitive silk worm. Perusal of literature in this aspect
reveals that the loss of body weight was noticed in silk
worm, when exposed to pesticides (Pant and Katiyar, 1983;
Venkata et al., 1989; Surendranath, 1993). Subacute
exposure to pesticides is reported to affect the
reproduction (Kuribayashi, 1980, 1981; Yamonoi,
1980).
Pesticide residues were also thought to be
transmitted to the silk worm eggs, embryos and pupae
affectd later generation (Watanabe and Takano, 1966a;
Kuwana et al., 1968). Along with chemical pesticides
neem based insecticides are known to possess several
adverse biological effects on insects like repellency,
antifecundity and inhibitory activity (Schmutterer,
1990;
Jothi et al., 1999; Medina et al., 2004; Tiwari et al.,
2006;
Kodandaram et al., 2008). Azadirachtin affect food
intake by exerting strong antifeedant effects against a
wide range of insect species (Meisner et al., 1981 a, b;
Ley et al., 1989; Warthen, 1989; Blaney et al., 1990;
Mordueluntz and Blackwell, 1993). Biological effects on
insects like repellency, antifecundity and inhibitory
activity (Schmutterer, 1990; Jothi et al., 1999; Medina et
al., 2004; Tiwari et al., 2006; Kodandaram et al., 2008).
Azadirachtin affect food intake by exerting strong
antifeedant effects against a wide range of insect
species (Meisner et al., 1981a, b; Ley et al., 1989;
Warthen, 1989; Blaney et al., 1990; Mordueluntz and
Blackwell, 1993).
Since Dichlorovos is widely used against a variety of
agricultural pests, particularly mulberry pests which
may attack silkmoth through their feeding on pesticide
sprayed leaves during development. Neem pesticide
also caused more than 80% larval mortality in many
insects. Hence in the present investigation an attempt
has been made to study the effect of Vijay neem and
Dichlorovos on the metamorphosis of mulberry silk
worm,
Bombyx mori. L.
1
Results and Discussion
Silkworm larvae fed with pesticide treated foliage
resulted in persistent growth inhibition at different
levels during metamorphosis. The silkworm larvae fed
with pesticides treated foliage caused growth
disruption in pupal and adult morphogenesis in a dose
dependent manner. When compared to Dichlorovos,
Vijay neem showed much morphogenetic inhibition
effect (Table 1). The present findings showed that
pesticide is effective in inhibiting larval growth and
inducing pupal and adult deformities in silk worm
(
Table 1). Such growth inhibitory effect of pesticide
ranging from delay in moulting with the production of
deformed insects, to the complete inhibition of growth
at high doses had been reported in various insect
species (Schmutterer, 1990).