LIBRO-CONGRESO-CITRUS

S12
S12O03
A new insect vector of Candidatus Liberibacter asiaticus, Cacopsylla (Psylla) citrisuga (Hemiptera:
Psyllidae)
Cen Y. 1 , Gao J. 2 , Deng X. 3 , Xia Y. 4 , Chen J. 5 , Zhang L. 1 , Guo J. 2 , Gao W. 1 , Zhou W. 3 , and Wang Z. 2
1 Lab. of Insect Ecology, South China Agricultural University, China; 2 Institute of Tropical and Subtropical Cash Crops, Yunnan Academy
of Agricultural Science, China; 3 Citrus Huanglongbing Research Laboratory, South China Agricultural University, China; 4 Center for
Integrated Pest Management, North Carolina State University, USA; and 5 Crop Diseases, Pests and Genetics Research, San Joaquin
Valley Agricultural Sciences Center, United States Department of Agriculture, USA. cenyj@scau.edu.cn
Nymphs and adults of the pomelo psyllid (Cacopsylla (Psylla) citrisuga Yang & Li) were collected from Huanglongbing
(HLB) symptomatic and Candidatus Liberibacter asiaticus (Las)-positive lemon trees (Citrus limon (L.) Burm.F.)
in Yunnan Province, China. DNA was extracted from groups of psyllid nymphs, individual late-stage nymphs and
groups of adults, and the samples were analyzed with nested-PCR (primers:1500R/27F, OI1/OI2c). The results
showed that 10 out of 24 group-nymphs samples, 12 out of 29 individual-late-stage nymph samples, 2 out of 3
group-adult samples were Las-positive. DNA was also extracted from group-nymph of the 1st, 2nd, 3rd, 4th and
5th instar, then subjected to nested-PCR detections. One out of 4 1st instar, 2 out of 4 2nd instar, 1 out of 3 3rd
instar, 1 out of 2 4th instar, and all 3 5th instar nymph samples were Las-positive. The amplified DNA fragment
was sequenced and was 99% similar to the 16S rRNA gene of Las strain psy62 in GenBank. Transmission study
showed that 12 out of 60 healthy lemon young plants were Las-positive after being fed by psyllid nymphs and
adults collected from infected trees for about 1 month. These results demonstrate that in addition to Asian
citrus psyllid (Diaphorina citri Kuwayama), C. (P.) citrisuga is another insect vector of Las.
S12O04
On the identity of orange jasmine and its relevance to Huanglongbing and Diaphorina citri.
Holford P. 1 , Nguyen C.H. 1 , Beattie G.A.C. 1 , Haigh A.M. 1 , Hasick N.J. 1 , Mabberley D.J. 2 , and Weston P.H. 2
1 Univeristy of Western Sydney, School of Science and Health, Australia; and 2 Royal Botanical Gardens, Sydney, Australia.
p.holford @ uws.edu.au
Orange jasmine, a common ornamental, is a favoured host of Diaphorina citri Kuwayama, the principal vector
of Candidatus Liberibacter asiaticus, the most widespread of three liberibacters that cause Huanglongbing.
Orange jasmine is also a transient host of the disease, but its identity has been subject to conjecture since
1747. It is widely regarded as Murraya paniculata (L.) Jack, but also as Murraya exotica L. Our morphological
(mostly leaves and leaflets) and molecular studies (6 chloroplast and the ITS rRNA operon regions) of the genus
indicated that it is Murraya exotica, probably from Southern China/Northern Vietnam, and that Murraya
paniculata represents a species that occurs in the Indonesian archipelago. The study also determined that
a species, Murraya asiatica ineditus, previously regarded as Murraya paniculata, occurs in mainland Asia
and that a fourth species, Murraya ovatifoliolata (Engl.) Domin., includes taxa formerly regarded as varieties
of Murraya paniculata: Murraya ovatifoliolata var. ovatifoliolata ineditus (small and large leaflet forms in
Australia) and Murraya ovatifoliolata var. zollingeri ineditus (from the eastern Indonesian archipelago). Two
possible hybrids, Murraya × omphalocarpa ineditus from Orchid Island, Taiwan and Murraya × cycloopensis
ineditus from Papua were identified. Murraya exotica is naturally associated with low altitude maritime and
riparian acid red soils, and Murraya asiatica with limestone hills. Of the four identified species, Murraya
exotica is the only one known to have been introduced to the Americas. There are no records of Murraya
paniculata or Murraya asiatica as hosts of liberibacters, nor of Murraya asiatica as a host of Diaphorina citri.
S12O05
Effect of HLB on the expression of calcium signals related genes
Parra C.C. 1 , Kunta M. 2 , and Louzada E.S. 1
1 Texas A&M University-Kingsville (TAMUK), Citrus Center, USA; and 2 Texas A&M University- Kingsville (TAMUK), Citrus Center, USA.
eliezer.louzada @ tamuk.edu
Citrus has been challenged for a long time by innumerable biotic and abiotic threats, and it has so far survived.
However, the introduction of the bacterium Ca. Liberibacter asiaticus (CLas), causal agent of citrus greening
194 - VALENCIA CONFERENCE CENTER, 18th-23rd NOVEMBER 2012