~ 45 ~
Journal of Entomology and Zoology Studies 2015; 3(4): 45-49
E-ISSN: 2320-7078
P-ISSN: 2349-6800
JEZS 2015; 3(4): 45-49
© 2015 JEZS
Received: 21-06-2015
Accepted: 24-07-2015
Hayat Badshah
Department of Plant Protection,
the University of Agriculture
Peshawar-Pakistan
Farman Ullah
Department of Plant Protection,
the University of Agriculture
Peshawar-Pakistan
Abid Farid
Department of Agriculture,
University of Haripur, Haripur-
Pakistan
Paul Andre Calatayud
IRD c/o ICIPE - African Insect
Science for Food and Health
NSBB (Noctuid Stem Borer
Biodiversity) team P.O. Box
30772-00100 Nairobi Kenya
Neil Crickmore
Department of Biochemistry
School of Life Sciences,
University of Sussex, Brighton
UK
Correspondence:
Hayat Badshah
Entomology Section,
Agricultural Research Institute
Tarnab Peshawar-Pakistan
Toxicity of Neem seed Azadirachta indica Juss
(Meliaceae) different solvents extracts against cotton
mealybug Phenacoccus solenopsis Tinsley
(Sternorrhyncha: Pseudococcidae) under
Laboratory conditions
Hayat Badshah, Farman Ullah, Abid Farid, Paul Andre Calatayud, Neil
Crickmore
Abstract
This study investigated the toxicity of neem treatments in comparison with Confidor 20% SL against
cotton mealybug Phenacoccus solenopsis Tinsley. The experiments were laid out under completely
randomized design (CRD) with six main treatments including untreated check under laboratory
conditions at Agricultural research Institute Tarnab, Peshawar-Pakistan during 2012/2013. Results
indicated that Confidor 20% SL and neem seed extracts (acetone and n-hexane extracts) caused 100 %
mortality of P. solenopsis after 48 hrs and one week duration respectively. Over all after a week
exposure, mortality trend was recorded as 100%, 97%, 88% and 67% by Neem seed n-Hexane extracts,
Neem seed Acetone extracts, Neem oil and Neem seed water extracts respectively for 3% concentration.
Similarly for 2% concentration it was recorded as 87%, 84%, 74% and 46% and for 1% concentration the
mortality trend was noted as 68%, 62%, 56% and 29% in n-Hexane, Acetone, Neem oil and Neem seed
water extracts respectively. The neem extracts and oil bioassay revealed that % mortality of P. solenopsis
was dose and time dependent. These findings provide clear indication that n-Hexane and Acetone are
good solvents for neem seed extracts preparation to be used against cotton mealybug in Pakistan.
However further study needs to be conducted to know the compatibility of these extracts against the
natural enemies in field as well as in laboratory conditions.
Keywords: Cotton mealybug, Neem seed extracts, organic solvents, toxicity
Introduction
Cotton mealybug Phenacoccus solenopsis Tinsley (Sternorrhyncha: Pseudococcidae) is a
polyphagous insect feeding on a large variety of plant species including fruits, vegetables,
crops and a few ornamentals belonging to Malvaceae, Solanaceae and Leguminaceae families
[1]
. In Pakistan, it was detected for the first time in 2005 on cotton and other cultivated plants in
Punjab and Sindh provinces
[2]
. In addition to the direct losses by sucking the phloem sap, its
feeding secretions (honeydew) cause additional losses to the plants by disturbing the
photosynthesis activity and inducing fungal contaminations
[3, 4]
.
Farmers mostly rely on insecticides for the control of insect pests including mealybug
[5]
.
However, the frequent use of these fast-acting chemicals against the insects has generated a
number of biological and environmental hazards including phytotoxicity, toxicity to non-target
organisms, environmental degradation, health hazards to farmers and they also may accelerate
development of the pest biotypes resistant to specific pesticidal chemicals
[6, 7]
. There is
therefore a need to search for new materials and innovative approaches for effective and
biodegradable pesticides for insect pest control.
This awareness has created worldwide interest in the development of alternative strategies,
including the re-examination of using plant derivatives against agriculturally important insect-
pests. Plant-derived materials are more readily biodegradable
[8]
. More than 2,400 plant species
have been tested for pest-control properties
[9, 10]
Neem tree, Azadirachta indica Juss (Meliaceae) is commonly known as neem or Dharak found
in Indo-Pak subcontinent. In Pakistan, neem tree is mostly found in southern areas i.e. Sindh
and Punjab regions. The tree contains bioactive ingredients and more than 100 chemical
compounds have been identified so far, but the most effective bio active compounds are