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A new mosaic disease of Amazon lily in Taiwan
W.-C. Wu and Y.-C. Chang*
Department of Plant Pathology and Microbiology, National Taiwan
University, Taipei, Taiwan 10617, Republic of China.
*ycchang@ntu.edu.tw
Accepted for publication 15/12/03
Mosaic symptoms were observed in leaves of Amazon lily (Eucharis
grandiflora) grown commercially in Taiwan (Fig. 1). Leaf extracts
caused necrotic local lesions when mechanically inoculated onto leaves
of Chenopodium amaranticolor, Chenopodium quinoa and
Gomphrena globosa, whereas seedlings of Nicotiana
benthamiana showed a systemic mild mosaic (Fig. 2). Transmission
electron microscopy showed flexuous rods, approximately 700-780 nm long,
in leaf extracts. In indirect ELISA, symptomatic plants tested positive
using a monoclonal antibody specific to the potyvirus group (Agdia Inc.,
Elkhart, IN, USA). Two potyviruses have been reported to infect Amazon
lily: Amazon lily mosaic virus (ALiMV) (Terami et al., 1993) and Hippeastrum
mosaic virus (HiMV) (Jayasinghe & Dijkstra, 1979). Based on
symptomatology, the virus isolate resembled ALiMV, as this causes a
systemic mosaic in N. benthamiana, whereas HiMV does not infect
this host (Brunt et al., 1996). Therefore, we tentatively
identified the virus as ALiMV, although the presence of previously
uncharacterised potyviruses cannot be excluded.
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Figure 1: The leaves of Amazon lily (Eucharis
grandiflora) infected by ALiMV showing mosaic and chlorotic streaks
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Figure 2: Inoculated Nicotiana benthamiana producing
mild mosaic on systemic leaves after 14 days
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The 3'-terminal region of ALiMV was amplified by RT-PCR from a total
RNA extract from diseased plants using a potyvirus-specific degenerate
forward primer (5’-GGBAAYAATAGTGGNCAACC-3’) and an oligo-dT reverse
primer. A 1.6-kb amplicon was cloned into pGEM-T® Easy
Vector (Promega, WI, USA), sequenced, and then analyzed using the GCG
program of Wisconsin Package Version 10.3 (Accelrys Inc., San Diego, CA,
USA). When compared to twenty-two potyviruses, the deduced amino acid
sequence of the coat protein, showed 40% identity to Dasheen mosaic
virus (DsMV) and 55% identity to Ornithogalum mosaic virus (OrMV).
References
Brunt AA, Crabtree K, Dallwitz MJ, Gibbs AJ, Watson L, Zurcher EJ,
1996. Plant Viruses Online: Descriptions and Lists from the VIDE
Database. Version: 20th August 1996.
[http://biology.anu.edu.au/Groups/MES/vide/]
Jayasinghe U, Dijkstra J, 1979. Hippeastrum mosaic virus and another
filamentous virus in Eucharis grandiflora. Netherlands Journal
of Plant Pathology 85, 47-65.
Terami F, Honda Y, Fukumoto F, 1993. A new potyvirus isolated from Eucharis
grandiflora, Amazon lily mosaic virus. Annals of the
Phytopathological Society of Japan 59, 334.
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