LIBRO-CONGRESO-CITRUS

(SIT) application. Both mass-trapping and the SIT are dependent on the availability of efficient species-specific
attractants. For the SIT the availability of attractants is critical for monitoring the size and composition of the
target and the sterile populations. The efficiency of an artificial attractant depends on its ability to deceive
the exquisite sensitivity and selectivity of an insect’s chemosensory system. Little is known about the genes,
receptors and the processes that mediate chemosensory behaviours in the medfly. We are characterizing
the medfly chemosensory system using functional molecular, protein, behavioral and electrophysiological
approaches.
The study of the molecular basis of the perception of odours and pheromones in C. capitata, apart from
providing new information on the reproductive biology of this invasive species, also represents the basis for
future developments. The identification of the specific odours that bind to proteins involved in chemoreception
could lead to the development of new attractants and repellents that could have an important role in
environmentally friendly biological control methods. This would form the basis for the extension of such
biotechnological approaches to other species of agricultural and medical importance. As such this represents
yet another example of the key role of the medfly as a model organism for innovative control programmes.
S13O06
Field infestation and suppression of the invasive fruit flies Bactrocera invadens on citrus in
Kenya.
Ekesi S.
International Centre of Insect Physiology and Ecology (ICIPE), Plant Health, Nairobi, Kenya. sekesi@icipe.org
Field infestation rates of the invasive fruit fly species, Bactrocera invadens on Citrus spp. was determined at
different localities in Kenya. The level of infestation varied with location ranging from 3.0 to 36%. At some of the
locations and especially at high elevations, B. invadens frequently shared the same fruit with the indigenous
fruit fly species Ceratitis capitata but often occurred at higher numbers than C. capitata. Among the five
Citrus species sampled, sweet oranges (Citrus sinensis) recorded the highest level of infestation compared
with the other species. There was a significant inverse relationship between numbers of flies per kg of fruits
and elevation at which citrus fruits were collected. Field trail were conducted on sweet oranges to compare
catches of B. invadens in Multilure trap baited with 4 commercial food-based attractants namely Mazoferm®,
Torula® yeast, Hymlure®, and Nulure®. Mazoferm and Torula yeast were the most effective attractants and
captured between 2.4-2.8 times and 3.2-4.1 times more flies, respectively than the standard Nulure. In field
suppression trials using Mazoferm-Spinosad bait spray, % reduction in B. invadens population relative to
the control was 82% at 4-weeks after bait spray and 94% at 8-weeks after treatment application. At harvest,
percentage fruit infestation was significantly lower in the treated orchards (5%) compared with the control
orchards (39%) and demonstrates the efficacy of bait spray for the management of B. invadens on citrus.
S13O07
Quarantine mitigation for Tephritid fruit fly pests in citrus.
Liquido N. J. 1 , and Griffin R. L. 2
1United States Department of Agriculture (USDA-APHIS-PPQ-CPHST), Plant Epidemiology and Risk Analysis Laboratory, USA; and
2United States Department of Agriculture (USDA-APHIS-PPQ-CPHST), Plant Epidemiology and Risk Analysis Laboratory, USA.
Nicanor.J.Liquido@aphis.usda.gov
The fruit flies of the family Tephritidae impose enormous constraints on the diversification of agricultural
production and expansion of agricultural trade around the world. Their polyphagous feeding habits and
persistent ecological adaptiveness distinguish them among the worst invasive pest species requiring vigilant
detection, effective suppression, and regimented area-wide eradication. Among the suitable host plants of
quarantine-significant fruit flies belonging to genera Anastrepha, Bactrocera, and Ceratitis are Citrus spp.
Rigorous quarantine procedures and regulatory safeguards are required and enforced to prevent the spread
of these fruit flies through legitimate international and domestic movement of citrus.
XII INTERNATIONAL CITRUS CONGRESS 2012 - 223
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