LIBRO-CONGRESO-CITRUS

was uniform under the non-UV-blocking films. Our results show that UV-blocking films can effectively limit
the spread of ACP in citrus grown in enclosed environments.
S16O11
Ontogenic variation in citrus flush shoots and its relation with host plant finding and acceptance
by Asian Citrus Psyllid (Hemiptera: Psyllidae)
Setamou M. 1 , and Patt J. M. 2
1 Texas A & M University-Kingsville Citrus Center (TAMUK-CC), Agriculture, Agribusiness and Environmental Sciences, USA; and 2 U.S.
Horticultural Research Laboratory (USDA-USHRL), Horticulture and Breeding Research, USA. mamoudou.setamou@tamuk.edu
The Asian citrus psyllid, Diaphorina citri (Hemiptera: Psyllidae) is a destructive insect mainly because it
vectors the bacterial pathogens that cause the deadly and incurable citrus greening disease. Diaphorina citri
adult females lay eggs and immature development occurs exclusively on new flush shoots of their Rutaceae
host plants. Although citrus trees are evergreen vegetation that holds green foliage all year round, D. citri
is particularly abundant in citrus groves when new flush shoots are present. Thus, population dynamics of
this pest are strongly determined by flush cycles of citrus trees. New flush shoots have distinctive physical
and chemical characteristics that may facilitate host finding by adult psyllids and their suitability for psyllid
oviposition and immature development. Consistent with this hypothesis, D. citri adults preferentially selected
younger flush shoots over mature ones for feeding and oviposition. Appearance of young flush shoots as
measured by their spectral reflectance, their softness and volatile composition provided evidence of their
roles in nutritional ecology of D. citri.
S16O12
Targeting juvenile hormone metabolic genes in the Asian citrus psyllid (Diaphorina citri) as a
strategy to reduce the spread of citrus greening disease.
Van Ekert E. 1 , Borovsky D. 2 , Powell C. A. 3 , Cave R. D. 1 , Alessandro R. T. 4 , and Shatters R. G. 4
1 Indian River Research and Education Center, University of Florida, Entomology and Nematology, USA; 2 Borovsky consulting, Vero
Beach, FL, USA; 3 Indian River Research and Education Center, University of Florida, Plant Pathology, USA; and 4 US Horticultural
Research Laboratory, USDA - ARS, USA. belgica@ufl.edu
Diaphorina citri Kuwayama, the Asian Citrus Psyllid (ACP), is a devastating citrus pest due to its transmission
of a phloem-limited bacterial pathogen, Candidatus Liberibacter asiaticus Jagoueix that causes citrus
greening. Psyllid control is a major part of effective greening disease management, and our research targets
perturbation of insect juvenile hormone metabolism as a new psyllid control strategy. Previous studies have
shown that application of a juvenile hormone (JH) analogue, pyriproxyfen, produces ovicidal/nymphicidal
effects, morphological abnormalities, and reduced fecundity in ACP adults. These observations prompted
us to identify JH biosynthetic and degradative pathways as targets for biologically-based control strategies,
including RNA interference, as alternatives to heavy reliance on broad-spectrum pesticides. First, candidate
genes/cDNAs encoding the JH metabolic enzymes, juvenile hormone acid methyl transferase (JHAMT) and
juvenile hormone esterase, were identified through computational analysis of the ACP genome. Second,
JHAMT cDNA was cloned, expressed in E. coli and a functional protein was purified. This JHAMT had a high
affinity for substrates leading to JHI and JHIII synthesis, making it plausible that both juvenoids are present
in the ACP. Results are discussed with respect to mechanism(s) of JH biosynthesis/catabolism in the ACP and
targeting this process as an interdiction point for a biorational ACP control strategy.
S16O13
Biological control of red scale on citrus on the central coast of New South Wales.
Dao H.T. 1 , Beattie G.A.C. 2 , Holford P. 2 , Spooner-Hart R. 2 , Meats A. 3 , and Burgess L. 3
1 Plant Protection Research Institute (PPRI), Vietnam; 2 University of Western Sydney (UWS), Australia; and 3 University of Sydney,
Australia. daothihang@hotmail.com
Most studies on the ecology and biological control of California Red Scale (Aonidiella aurantii) in citrus orchards
have been undertaken in warm dry regions where species of Aphytis, particularly A. melinus, are viewed as the
XII INTERNATIONAL CITRUS CONGRESS 2012 - 279
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