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Occurrence and distribution of citrus leprosis virus (CiLV-C) in Honduras, Central America
First report of Tomato leaf curl Joydebpur virus infecting chilli in
India
S.L. Shih1, W.S. Tsai1,
S.K. Green1* and D.
Singh2
1
AVRDC-The World Vegetable Center, Shanhua,
Tainan, Taiwan 74199, Republic of China
2
Punjab Agricultural University, Ludhiana 141004, Punjab, India
*skg@avrdc.org
Accepted for publication 08/09/06 Symptoms of mild
yellowing, severe leaf curling, leaf
distortion, stunting and blistering (Fig. 1) were observed in June, 2004 in
chilli (Capsicum annuum) fields in Ludhiana, Punjab State, India. DNA
was extracted from 3 such symptomatic plants and tested for the presence of
begomoviral DNA-A, DNA-B and associated satellite DNA by polymerase chain
reaction (PCR) using previously described primer pairs (Shih et al.,
2003). In all 3 samples, the expected 1.4kb DNA-A fragment for begomovirus was
obtained and DNA-beta of 1.3 kb was detected using the Beta01/Beta02 primers
(Briddon et al., 2002). DNA-B was not detected.

Figure 1: Mild yellowing, severe leaf curling, leaf distortion, stunting and
blistering symptoms on chilli
Based on the sequence of the 1.4 kb DNA-A
product, specific primers were designed to complete the DNA-A sequence. The
DNA-A consisted of 2767 nucleotides (DQ673859) and was found to contain the
geminiviral conserved nanosequence TAATATTAC in the intergenic region. BLAST
analysis was conducted with geminivirus sequences available in the GenBank
database and MegAlign software (DNASTAR, Madison, WI) was used for further
comparisons. Highest full length DNA-A sequence identity of 90.8% was found
with a recently described tomato begomovirus from India (DQ629103). However,
the genome organization of the chilli begomovirus from Punjab is similar to that
of Tomato leaf curl Joydebpur virus (ToLCJV, AJ875159) from Bangladesh
(Maruthi et al., 2006), with which it shares 90.3% sequence identity.
Both of these viruses contain the V1, V2, C1, C2, C3 and C4 predicted opening
reading frames (ORFs), and an additional predicted ORF C5 of 849 nt (282 amino
acids) on the complementary strand which is absent in DQ629103. Only low
sequence identities (ranging from 73-80%) were obtained with other incompletely
sequenced (771-1087 nt) Indian chilli begomoviruses reported from Lucknow,
Bahraich and Kanpur (DQ119573, AY883570, DQ431845, DQ431846, DQ431844 and
DQ141676), which are all tentative strains of Tomato leaf curl New Delhi
virus(ToLCNDV).
On the basis of DNA-A sequence analysis, the
ICTV species demarcation of 89% sequence identity and genome organization, the
Punjab chilli begomovirus is a provisional strain of ToLCJV described from
tomato in Bangladesh. To our knowledge, this is the first report of ToLCJV
naturally occurring on chilli in India. Besides the two chilli infecting
begomoviruses mentioned above, there seems to be at least one more distinct
begomovirus in India. This partially-sequenced (995 nt, DQ445255) begomovirus
(Senanayake et al., 2006) is considered a tentative strain of the
Chilli leaf curl virus from Pakistan (AF336806) and shares only 82% sequence
identity with chilli begomovirus from Punjab. The presence of 3 distinct chilli
begomoviruses needs to be considered for developing stable begomovirus virus
resistant chilli cultivars for India.
References
Briddon RW, Bull SE, Mansoor S,
Amin I, Markham PG, 2002. Universal primers for the PCR-mediated amplification
of DNA-ß: a molecule associated with monopartite begomoviruses. Molecular
Biotechnology 20, 315-318.
Maruthi MN, Rekha AR, Alam SN,
Kader, KA, Cork A, Colvin, J, 2006. A novel begomovirus with distinct genomic
and phenotypic features infects tomato in Bangladesh. Plant Pathology
55, 290. (First published online:
New Disease Reports 11, http://www.bspp.org.uk/ndr/
july2005/2005-46.asp)
Senanayake DMJB, Mandal B, Lodha
S, Varma A, 2006. First report of Chilli leaf curl virus affecting chilli
in India. New Disease Reports 13
[http://www.bspp.org.uk/ndr/july2006/2006-35.asp]
Shih SL, Tsai WS, Green SK, Khalid
S, Ahmad I, Rezaian MA, 2003. Molecular characterisation of tomato and chilli
leaf curl begomoviruses from Pakistan. Plant Disease 87, 200.
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