Vol.18_No.2 - Pesticide Alternatives Lab - Michigan State University

Spring 2009 Resistant Pest Management Newsletter Vol. 18, No. 2
resistant to pyrethroids. Populations in other parts of
North America have been shown to exhibit resistance
to pyrethroids as well as organophosphates (Kanga et
al. 2003; Kanga et al. 1997). Recent increased losses
to OFM threaten the viability of apple and peach
production in southern and southwestern IL and the
lower Midwest.
The focus of an ongoing project at the
University of Illinois is to describe baseline
susceptibility for larvae of two OFM colonies to key
insecticides, including newly available reduced-risk
insecticides and insecticides approved by OMRI
(Organic Materials Review Institute).
Initial efforts have focused on
chlorantraniliprole, spinetoram, and acetamiprid. To
assess concentration-response relationships for these
insecticides neonates were placed on diet blocks
containing a range of concentrations (approximately
200 larvae per dose). Mortality was assessed after 96
hours. Two colonies are being tested separately, a longterm
lab colony from Rutgers University and a colony
established from a southwestern Illinois field
population (Calhoun County) in the summer of 2007.
The LC50s expressed as ppm in diet, for Rutgers and
Calhoun colonies respectively were 0.077, 0.078 for
chlorantraniliprole; 0.040, 0.057 for spinetoram; and
0.300, 0.402 for acetamiprid. The LC90s expressed as
ppm in diet for Rutgers and Calhoun colonies
respectively were 0.281, 0.382 for chlorantraniliprole;
0.136, 0.207 for spinetoram; and 0.470, 0.667 for
acetamiprid.
Acknowledgements
The authors thank Jackie Robertson (LeOra Software)
for her analytical assistance.
Literature Cited
Kanga, L., Pree, D., van Lier, J., and Walker, G. 2003. Management
of insecticide resistance in oriental fruit moth (Grapholita
molesta; Lepidoptera: Tortricidae) populations from Ontario.
Pest Management Science. 59:921-927.
Kanga, L., Pree, D., van Lier, J., and Whitty, J. 1997. Mechanisms of
resistance to organophosphorus and carbamate insecticides in
oriental fruit moth populations (Grapholita molesta Busck)
Pestic. Biochem. Physiol. 59:11-23.
Robertson, J.L., Russell, R.M., Haiganoush, P.K., and Savin, N.E.
2007. Bioassays with arthropods. 2nd ed. CRC pp224.
Moneen M. Jones and Richard Weinzierl
University of Illinois, Urbana, IL
Spatial Analyzed Region of Risk to Dengue Hemorrhagic Fever (DHF) and
Aedes aegypti Linn Resistance to Temefos in Padang
The objective of this research is to investigate
the Aedes aegypti resistance to temefos in sub-district
and also know the region of risk to occurrence of DHF.
The research is observing the larvae density based on
the Breteau Index (BI), and quasi experimental 3 th and
4 th larvae of Aedes aegypti with ovitrap, which were
colonized for biochemical tests with colour eye score
and Elisa reader l 450 nm.
The resistance was detected from esterase
enzyme activity (a-acetat napthyl and β-acetat napthyl)
showing a change of colour as a reaction to the
homogenate micro-plate and filter paper spot
technique. The results went from uncoloured to deep
blue, as according to resistance level from sensitive
(SS), tolerant (RS) to resistance (RR). Region of risk
based distribution data contained water.
The results of the research for esterase
enzyme activity a-acetat napthyl is tolerant (RS) by a
colour eye score mean of 2, with ELISA reader (SS),
AV 0.900 = 3.67 %. While that
β-acetat napthyl is sensitive (SS) by a colour eye score
mean of 2.05 and with ELISA reader (SS) = 82.34 %,
(RS) = 14.67 % and (RR) = 2.99 %.
The results analyzed by Oneway ANOVA
significantly indicated that there was statistically
significant Aedes aegypti resistance to temefos, and a
multi comparison test of Post Hoc by Turkey's HSD
got results of a resistance difference between subdistricts
Andalas, Jati, and Teluk Bayur with other subdistricts.
Spatial analyzed the results of the region of risk
occurrence of DHF based on Breteau Index (BI). The
distribution data obtained by the results were 42.86 %
of sub-districts at medium risk and 21.43 % in danger.
For the Padang city (BI), the mean was 35 which is a
high risk.
Keywords: Aedes aegypti – Resistance – Temefos –
Spatial - Breteau Index
AIDIL ONASIS, SKM, M. Kes.
Lecturer Environmental health Department
Health Politechnic Padang
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