Fourth International Bemisia Workshop International Whitefly ...

Journal of Insect Science | www.insectscience.org ISSN: 1536-2442
Novel Technique for the Control of Insect
Growth Regulator Resistant B-Biotype
Bemisia Tabaci in Australia
Robin Gunning 1 , Emma Cottage 2 , and Valerio
Borzatta 2
1 New South Wales Department of Primary Industries, Tamworth,
Australia.
Correspondence: robin.gunning@dpi.nsw.gov.au
2 Endura, SpA, Bologne, Italy
B-biotype Bemisia tabaci (the silverleaf whitefly), is a
serious pest on cotton, grain, legume and horticultural
crops in Australia. The silverleaf whitefly entered
Australia resistant to most organophosphates,
carbamates and pyrethroids and has since developed
resistance to most other insecticides used for control,
including insect growth regulators (IGRs), buprofezin
and pyriproxyfen. There is cross-resistance between
the two IGRs. IGR-resistance in the silverleaf whitefly
is a major threat to the economic production of cotton
in Australia and field control problems have occurred.
IGR-resistance in Australian populations of B-biotype
B. tabaci appears largely to be due to overproduced
esterase isoenzymes, which apparently sequester the
IGR insecticides. In this work, we investigated
synergism with an esterase inhibitor, as a means to
overcome IGR resistance in B-biotype B. tabaci.
Esterase inhibitors such as organophosphates and
piperonyl butoxide are commercially available, as they
are used on cotton in Australia, in tank mixes with
pyrethroids. Pyriproxyfen-resistant B-biotype B. tabaci
nymphs were bioassayed with pyriproxyfen after
exposure (by leaf dip) to a non-toxic dose of
formulated piperonyl butoxide (PBO). Data indicated
that PBO completely synergised pyriproxyfen and
suppressed resistance. The use of synergists to control
IGR-resistance could give effective control of
B-biotype B. tabaci on cotton in Australia.
Performances of Three Types of Insect
Screens as a Physical Barrier Against
Bemisia tabaci and their Impact on
TYLCV Incidence in Greenhouse Tomato
in the Souss Valley of Morocco
A. Hanafi
IAV Hassan II, Complexe Horticole d’Agadir, Department of Plant
Protection, IPP Unit, Agadir Morocco.
Correspondence: hanafi@iavcha.ac.ma
Tomato yellow leaf curl virus (TYLCV) was
introduced to Morocco in 1998. Since then it has
become the major challenge for tomato farmers in
Morocco. The only way to seriously control the disease
is by effectively controlling the vector. Although
pesticides will remain an important tool for pest
management in greenhouse crops, non chemical
methods must be introduced to reduce damage to the
environment and to delay build up of insecticide
resistance. Screens have been found to be an efficient
method for reducing the entry of pests into the
greenhouse, and hence for reducing the number of
insecticide applications targeting the insect pests and
vectors. In this study we report on observations that
were conducted in three greenhouses belonging to
private farmers and which are equipped with three
different types of insect screens 10*14, 10*20 and
10*22. We report on whitefly captures in sticky traps
as well as TYLCV incidence in the tomato crop. The
results indicate that the insect-net 10*22 gave the best
exclusion of whiteflies followed by the insect net
10*20, whereas the screen 10*14 showed very poor
performances. TYLCV incidence at the end of the crop
cycle was estimated at 4%, 16% and 76% in the
greenhouses equipped wit the screen 10*22, 10*20 and
10*14, respectively.
Looking for Bemisia tabaci biotype Q in
Florida: Results of biotype sampling from
2005–2006.
Greg S. Hodges 1 and Cindy L. McKenzie 2
1 Florida Department of Agriculture and Consumer Services,
Division of Plant Industry, Gainesville, Florida, USA.
Correspondence: hodgesg@doacs.state.fl.us
2 USDA, U.S. Horticultural Research Lab, Fort Pierce, Florida, USA
In March 2005, Arizona scientists identified the Q
biotype of Bemisia tabaci from Poinsettia plants that
originated from California. Soon after, Florida began
forming a plan for surveying, identifying and dealing
with the Q biotype. Efforts for surveying began
immediately in March 2005 and have continued
through present day. Pest alerts and educational efforts
from the FDACS-DPI and the University of Florida
have played a key role in getting involvement from
growers, extension agents and agricultural inspectors.
As of November 1, 2006 there have been a total of five
Counties in Florida in which the Q biotype has been
detected.
The Biotypes B and Q of Bemisia tabaci in
Israel – Distribution, Resistance to
Insecticides and Implications for Pest
Management
R. Horowitz 1 , Svetlana Kontsedalov 2 , V. Khasdan 1 , H.
Breslauer 1 , and I. Ishaaya 2
1 Dept. of Entomology, ARO, Gilat Research Center, Israel.
Correspondence: hrami@volcani.agri.gov.il
2 Dept. of Entomology, ARO, The Volcani Center, Bet Dagan, Israel
Two biotypes of the whitefly, Bemisia tabaci
(Gennadius) (Hemiptera: Aleyrodidae), have been
documented from Israel. Biotype B was recognized in
Journal of Insect Science: Vol. 8 | Article 4 23