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Journal of Entomology and Zoology Studies 2017; 5(3): 159-162
E-ISSN: 2320-7078
P-ISSN: 2349-6800
JEZS 2017; 5(3): 159-162
© 2017 JEZS
Received: 21-03-2017
Accepted: 22-04-2017
B Chiranjeevi
Department of Entomology, Sri
Krishnadevaraya College of
Agricultural Sciences,
Anantapur-515001 (ANGRAU,
Bapatla), Andhra Pradesh,
India.
SV Sarnaik
PG Entomology Student,
Department of Entomology,
College of Agriculture,
Badnapur-431202 (VNMKV,
Parbhani), Maharashtra, India
Correspondence
B Chiranjeevi
Department of Entomology, Sri
Krishnadevaraya College of
Agricultural Sciences,
Anantapur-515001 (ANGRAU,
Bapatla), Andhra Pradesh,
India.
Bioefficacy of promising insecticides against
maggot population of pigeonpea pod fly,
Melanagromyza obtusa (Malloch)
B Chiranjeevi and SV Sarnaik
Abstract
The present studies revealed the treatment with chlorantriniliprole 18.5 SC @ 30 g a.i. per ha was found
best with minimum maggot population of M. obtusa at first and second spray i.e. 34.33, 16.33, 11.67,
10.67 and 18.00; and 30.33, 34.33, 12.00, 9.33 and 19.33 maggots per 100 pods on one, three, seven, ten
and fourteen days after first and second spray and it was followed by neem oil @ 3%. The least effective
treatment was Eucalyptus oil @ 5% with maximum population at first and second spray i.e. 44.67, 42.67,
38.67, 39.33 and 46.33; and 40.33, 44.67, 38.00, 35.00 and 46.00 pod fly maggots per 100 pods at one,
three, seven, ten and fourteen days after first and second spray. The result revealed that
chlorantriniliprole 18.5 SC @ 30 g a.i. per ha was found best treatment in respect of minimum maggot
population after the both insecticidal spray.
Keywords: Bioefficacy, Insecticides, Maggots, Melanagromyza obtusa, Pigeonpea and Pod fly
Introduction
Pigeonpea [Cajanus cajan (L.) Millsp.] is the second important pulse crop grown in India and
commonly known as red gram or tur or arhar
[1, 2]
. Pigeonpea is one of the most important
pulse crop, widely grown by small farmers in the semi-arid tropics as a backyard subsistence
crop being cultivated in more than 25 countries of the world
[3]
. More than 300 species of
insect species have been reported infesting pigeonpea crop
[4]
of which pod fly,
Melanagromyza obtusa (Malloch) is of regular occurrence, causing 10-80% damage
[5, 6]
and
estimated to cause a loss of US$ 256 million annually
[7]
. The pod fly lays eggs in immature
pods and feeds on developing seeds. The infested immature pods do not show external
evidence of damage until the fully grown larvae chew exit holes in the pod walls
[8]
. Till date,
chemicals are the only available efficient strategy against M. obtusa yet it involves several
limitations like no promising management of the pest even after two or three applications of
insecticides, the crop still undergo considerable losses and also the insecticides are mostly
unsafe to natural enemies and also cause hazards to mankind. The insecticides which have
ovicidal and translaminar action to create the lethal concentration in host at infestation points
may be effectual.
[6, 9, 10]
conducted several field studies to determine the efficacy of several
insecticides applied alone for the control of pod fly. However, these findings did not find
acceptability and led to partial success. Insecticides that should leave lesser residues and pose
lesser environmental threat have become imperative
[11]
. Exploring new insecticides with lesser
residues, lower environmental threat, novel mode of action and more remunerative has become
imperative. Keeping this in view, therefore the present studies were carried out to evaluate the
bioefficacy of promising insecticides against maggot population of pigeonpea pod fly,
Melanagromyza obtusa (Malloch).
2. Materials and Methods
The field experiment was conducted at Research Farm, Agricultural Entomology Unit,
Agricultural Research Station, Badnapur (VNMKV, Parbhani), Maharashtra, India during
Kharif season of 2015-16 to determine the bioefficacy of promising insecticides against
maggot population of pigeonpea pod fly, Melanagromyza obtusa (Malloch). The experiment
was laid out in randomized block design (RBD) with three replications. Total 33 plots of 5.4 m
X 4.8 m size were sown with 30 cm X 60 cm spacing by using Cv. BDN-711. Eleven
treatments including untreated control were imposed in all three replication randomly.