Lily Symptomless Virus Research Articles

Extraction of total nucleic acid based on silica-coated magnetic particles for RT-qPCR detection of plant RNA virus/viroid

In this study, a nucleic acid extraction method based on silica-coated magnetic particles (SMPs) and RT-qPCR assay was developed to detect Arabis mosaic virus (ArMV), Lily symptomless virus (LSV), Hop stunt viroid (HSVd) and grape yellow speckle viroid 1 (GYSVd-1). The amplification sequences of RT-qPCR were reversely transcribed in vitro as RNA standard templates. The standard curves covered six or seven orders of magnitude with a detection limit of 100 copies per each assay. Extraction efficiency of the SMPs method was evaluated by recovering spiked ssRNAs from plant samples and compared to two commercial kits (TRIzol and RNeasy Plant mini kit). Results showed that the recovery rate of SMPs method was comparable to the commercial kits when spiked ssRNAs were extracted from lily leaves, whereas it was two or three times higher than commercial kits when spiked ssRNAs were extracted from grapevine leaves. SMPs method was also used to extract viral nucleic acid from15 ArMV-positive lily leaf samples and 15 LSV-positive lily leaf samples. SMPs method did not show statistically significant difference from other methods on detecting ArMV, but LSV. The SMPs method has the same level of virus load as the TRIzol, and its mean virus load of was 0.5log10 lower than the RNeasy Plant mini kit. Nucleic acid was extracted from 19 grapevine-leaf samples with SMPs and the two commercial kits and subsequently screened for HSVd and GYSVd-1 by RT-qPCR. Regardless of HSVd or GYSVd-1, SMPs method outperforms other methods on both positive rate and the viroid load. In conclusion, SMPs method was able to efficiently extract the nucleic acid of RNA viruses or viroids, especially grapevine viroids, from lily-leaf or grapevine-leaf samples for RT-qPCR detection.

Reverse Transcription Polymerase Chain Reaction-based System for Simultaneous Detection of Multiple Lily-infecting Viruses.

A detection system based on a multiplex reverse transcription (RT) polymerase chain reaction (PCR) was developed to simultaneously identify multiple viruses in the lily plant. The most common viruses infecting lily plants are the cucumber mosaic virus (CMV), lily mottle virus (LMoV), lily symptomless virus (LSV). Leaf samples were collected at lily-cultivation facilities located in the Kangwon province of Korea and used to evaluate the detection system. Simplex and multiplex RT-PCR were performed using virus-specific primers to detect single-or mixed viral infections in lily plants. Our results demonstrate the selective detection of 3 different viruses (CMV, LMoV and LSV) by using specific primers as well as the potential of simultaneously detecting 2 or 3 different viruses in lily plants with mixed infections. Three sets of primers for each target virus, and one set of internal control primers were used to evaluate the detection system for efficiency, reliability, and reproducibility.

Specific and Rapid Detection of Lily symptomless virus and Arabis mosaic virus in Lily by Dual IC-RT-PCR

Lily symptomless virus (LSV) and Arabis mosaic virus (ArMV) cause severe losses of quantity and quality of lily flower and bulb production. Specificity, sensitivity and speed of detection methods for viruses need to be improved greatly to prevent LSV and ArMV from spreading from infected lilies. A dual IC-RT-PCR procedure for detection was developed in which the antibodies of LSV and ArMV were mixed and the mixture used to coat the PCR tubes. The particles of the two viruses were captured by the respective antibodies. Interference by other RNA viruses in infected lily was eliminated in the RT-PCR. Also, an RNA extraction step was omitted. The dual IC-RT-PCR products of LSV and ArMV were 521 bp and 691 bp, respectively. The specificity of the method was validated; only LSV and ArMV of four viruses were detected by dual IC-RT-PCR. The sensitivity of the detection method is 1 mg leaf tissue and higher than DAS-ELISA due to enrichment by dual immunocapture.

The Occurrence of the Viruses in Tulip Crops in Poland

Abstract The viruses infecting tulips have a big influence on the yield and the quality of bulbs and forced flowers. Commercial bulb production is based on clonal propagation, which leads to the accumulation of viruses. Among 22 viruses occurring in tulips, the most common and the most dangerous are Tulip breaking virus, TBV; Tobacco necrosis virus, TNV; Lily symptomless virus, LSV; Cucumber mosaic virus, CMV and Tobacco rattle virus, TRV. The aim of the research was to check which viruses occur most often on Polish tulip plantations. The research was done on two tulip (Tulipa L.) cultivars ‘Strong Gold’ and ‘Leen van der Mark’ grown at 3 farms situated in different parts of Poland (Warsaw Region, Pomerania and Podlasie) during 2006-2007, and then at 2 farms located in Warsaw Region during 2008-2011. Five of the most important viruses infecting tulips (TBV, TNV, LSV, CMV, and TRV) were detected by double antibody sandwich enzyme-linked immunosorbent assay (DAS-ELISA) in leaves and in bulbs during the period 2006-2010. In the last year of the research two different strains of TRV were detected (TRV-J and TRV-F) and Tulip virus X (TVX) as well. Search for viruses showed that most often TBV virus was detected both in the leaves and the bulbs regardless of the year and plantations. Yellow flowering cultivar ‘Strong Gold’ was infected by viruses more often than in bi-coloured (with red) ‘Leen van der Mark’, because of the difficulties with effective roguing of infected plants due to inconspicuous symptoms of virus infections on yellow coloured flowers. Other viruses were detected sporadically, however increasing occurrence of LSV and TRV was noticed from year to year. In 2011, TVX virus was detected in a few plants of ‘Strong Gold’ and it was the first case of detection of this virus in tulip in Poland.

Identification of Lily symptomless virus Infecting Lilium martagon ‘Pink Taurade’ in Ohio

The results presented here represent the first confirmed report of Lily symptomless virus (LSV) infecting Lilium spp. in Ohio. Accepted for publication 21 June 2013. Published 14 August 2013.

Development of an Indirect ELISA and Immunocapture RT-PCR for Lily Virus Detection

Multiple viruses such as Lily symptomless virus (LSV), Lily mottle virus (LMoV), and cucumber mosaic virus (CMV) are the most prevalent viruses infecting lilies in Korea. Leaf samples and bulbs showing characteristic symptoms of virus infection were collected from Gangwon, Chungnam, and Jeju provinces of Korea in 2008-2011. Coat protein (CP) genes of LSV and LMoV were amplified from collected samples by reverse transcription-polymerase chain reaction (RT-PCR) and cloned into a pET21d(+) expression vector to generate recombinant CPs. The resulting carboxy-terminal His-tagged CPs were expressed in Escherichia coli strain BL21(DE3) by isopropyl-1-thio- beta-D-galactoside induction. The recombinant proteins were purified using Ni-NTA agarose beads, and the purified proteins were used as an immunogen to produce polyclonal antibodies in rabbits. The resulting polyclonal antisera recognized specifically LSV and LMoV from infected plant tissues in Western blotting assays. Indirect enzyme-linked immunosorbent assay and immunocapture RTPCR using these polyclonal antisera were developed for the sensitive, efficient, economic, and rapid detection of Lily viruses. These results suggest that large-scale bulb tests and economic detection of Lily viruses in epidemiological studies can be performed routinely using these polyclonal antisera.

Detection of five viruses infecting dormant bulbs by TaqMan-based real-time RT-PCR

Dormant bulbs may be infected by a number of viruses which are of potential economic importance for the horticultural industry. Five important viruses in bulbs were successfully detected by TaqMan-based real-time one-step RT-PCR assays: Arabis mosaic virus (ArMV), Cucumber mosaic virus (CMV), Lily symptomless virus (LSV), Tobacco rattle virus (TRV) and Tulip virus X (TVX). Nucleic acid of appropriate quality and quantity for RT-PCR was extracted from nine bulb species using the Qiagen RNeasy plant mini kit. Depending on the assay, the sensitivity of the real-time RT-PCRs varied from being the same sensitivity to 1,000 times more sensitive than the respective conventional RT-PCRs. The reliability of the TVX real-time RT-PCR was further assessed against conventional RT-PCR using leaves and bulbs of 24 Tulipa × hybrida plants. TVX was detected in twice the number of leaf samples than bulb samples for both conventional and real-time RT-PCRs.

RAPID DETECTION OF LILY SYMPTOMLESS VIRUS WITH CdTe QUANTUM DOTS BY FLOW CYTOMETRY

Lily symptomless virus (LSV) is the most common lily virus, being detected in many species and hybrids. We established a microsphere-based fluorescent immunoassay for the determination of LSV, using a polyclonal antibody against LSV covalently bound to carboxy-modified microspheres able to capture LSV antigen. A monoclonal antibody against LSV conjugated to quantum dots (QDs) was used as a fluorescent probe, enabling LSV to be fluorescently detected by a combination of encoded beads and QDs. This method was 16 times more sensitive than ELISA in the detection of LSV, and could potentially be applied to the simultaneous detection of inhomogeneous matter.

Sequence and structure prediction of RNA-dependent RNA polymerase of lily symptomless virus isolated from L. × ‘Casablanca’

The DNA sequence of the RNA-dependent RNA polymerase (RdRp) gene of lily symptomless virus (LSV), a lily-infecting member of the genus Carlavirus, was determined from nine overlapping cDNA fragments of different sizes. The complete sequence of this RdRp gene (HM070294) consisted of 5,847 nucleotides coding for a protein of 220 kDa. It had 97-98% sequence identity with RdRps of other known isolates at both the DNA and the amino acid level. Phylogenetic analysis indicated that this RdRp (designated as RdRp-DL) was closely related to the RdRp of the Korean isolate (AM516059), as well as to the RdRps from Passiflora latent virus (PLV) and Kalanchoe latent virus (KLV) of the genus Carlavirus. Hydrophobic analysis of RdRp-DL revealed a hydrophobic N-terminus and a hydrophilic C-terminus. Helices and Loops were the major secondary structures of RdRp-DL. In addition, RdRp-DL also had three coil structures. Four conserved domains were identified: typoviral methyltransferase, RNA-dependent RNA polymerase, P-loop-containing nucleoside triphosphate hydrolases and carlavirus endopeptidase. A model of the tertiary structure predicted by I-TASSER was obtained for each of these conserved domains. This is the first report of a detailed phylogenetic analysis of LSV RdRp with those of other members of the genus Carlavirus, and the first to predict the domain structures of LSV RdRp.

Production of Virus-free Bulblets by Meristematic Tip Culture with Antiviral Chemical in Lilium brownii var. colchesteri

Lilium brownii var. colchesteri has unique and ornamental floral characteristics in graceful harmony with flower and anther colors, flower shape, elegant fragrance, and flower color change from yellowish cream to white during anthesis. There are, however, few accessions conserved in Japan up to the present, and they often show abnormally shaped flowers and mosaic leaves seemingly due to virus infection. Virus-free bulblets were established by combining meristematic tip culture and chemotherapy. At initial diagnosis with RT-PCR, Cucumber mosaic virus (CMV), Lily mottle virus (LMoV) and Lily symptomless virus (LSV) were detected from leaf tissues of the mother plants. All regenerated bulblets obtained by meristematic tip culture of the mother plants were still infected by at least one of the viruses. The meristematic tip of the bulblets infected with either LSV or LMoV was selected for subsequent culture with 2,4-dioxohexahydro-1,3,5-triazine (DHT), an antiviral chemical. LSV was eliminated successfully in mericlones from bulblets with LSV, whereas LMoV was not from those with LMoV. The virus-free bulblets were transferred to new medium without DHT, and multiplied by in vitro scaling. They were then acclimated in a phytotron glass room at 20°C. The plants were confirmed to be virus-free after 18-months’ acclimation. It was concluded that the combination of meristem tip culture and chemotherapy is practical for producing virus-free plants of L. brownii var. colchesteri.

Detection and Frequency of Lily Viruses in Argentina.

In a survey of lily growing fields in various regions of Argentina, three viruses, Lily symptomless virus (LSV), Lily mottle virus (LMoV), and Cucumber mosaic virus (CMV), were found in Longiflorum, Asiatic, Oriental, Longiflorum × Asiatic (LA), and Oriental × Trumpet (OT) hybrids. The areas surveyed were between latitude 26° 56' S and 43° 03' S, and longitude 65° 21' W and 71° 29' W. Virus detection was performed by double-antibody sandwich enzyme-linked immunosorbent assay (DAS-ELISA) using polyclonal antiserum. In infected samples, viruses detected in decreasing order were LSV (60.5%), LMoV (51.0%), and CMV (28.7%) present in single or mixed infections. Virus infection varied among tested hybrids from 36.0% (Oriental Montecristo) to 94.7% (Lilium longiflorum Avita) in 2006 and from 38.9% (OT Yelloween) to 82.1% (LO Triumphator) in 2007, with an overall incidence of 64.1 and 70.7% in 2006 and 2007, respectively. A variation in virus incidence among localities was also observed. The highest virus incidence (89.6 and 87.6% in 2006 and 2007, respectively) was observed in Bahía Blanca (38° 44' S, 62° 16' W). The lowest virus incidences, detected in Trevellin (43° 03' S, 71° 29' W) and in Malargüe (35° 28' S, 69° 35' W), were 47.4 and 48.6% in 2006 and 2007, respectively. Moreover, a different distribution of each virus was observed between localities. The high occurrence of viruses infecting lily crops in Argentina could be due to both the use of infected bulbs for propagation and the lack of preventive virus vector control measures.

Expression, purification and characterization of the Lily symptomless virus coat protein from Lanzhou Isolate

BackgroundLily symptomless virus (LSV) is widespread in many countries where lily are grown or planted, and causes severe economic losses in terms of quantity and quality of flower and bulb production. To study the structure-function relationship of coat protein (CP) of LSV, to investigate antigenic relationships between coat protein subunits or intact virons, and to prepare specific antibodies against LSV, substantial amounts of CP protein are needed.ResultsThus, full-length cDNA of LSV coat protein was synthesized and amplified by RT-PCR from RNA isolated from LSV Lanzhou isolate. The extended 33.6 kDa CP was cloned and expressed prokaryoticly and then purified by Ni-ion affinity chromatography. Its identity and antigenicity of recombinant CP were identified on Western-blotting by using the prepared anti-LSV antibodies.ConclusionsThe results indicate that fusion CP maintains its native antigenicity and specificity, providing a good source of antigen in preparation of LSV related antibodies. Detailed structural analysis of a pure recombinant CP should allow a better understanding of its role in cell attachment and LSV tropism. This investigation to LSV should provide some specific antibodies and aid to development a detection system for LSV diagnostics and epidemiologic surveys.

Production of Lily Symptomless Virus-free Plants by Shoot Meristem Tip Culture and In Vitro Thermotherapy

To produce virus-free plants, a simple and original protocol was established by combining several techniques: repeated shoot meristem excision before and during in vitro culture and thermotherapy applied to bulblets in vitro. Lily symptomless virus (LSV) is a major virus that decreases plant growth vigor and the quality of cut flowers, yet infected plants show no distinct symptoms. Stock bulbs of pollenless Asiatic hybrid lily (L. × elegans Thunb) lines (‘409’ and ‘599’) were used as explant. Shoot meristems were excised and micropropagated. Thermotherapy (42 days at 35 °C) was applied to in vitro growing bulblets and a second meristem cut was then made from heat-treated material. Leaf tissues from bulblets formed before or postheat treatments were analyzed either by enzyme-linked immunosorbent assay or by reverse transcriptase–polymerase chain reaction. Line ‘499’ produced LSV-free plants without heat treatment, but line ‘599’ produced LSV-free plants only after heat treatment. The virus-free lily bulblets grew vigorously in vitro and acclimatized promptly. It is suggested that thermotherapy given to in vitro growing bulblets effectively eliminated the virus and induced a fast and efficient micropropagation technique for virus-free mother plant stock.

Recombination and phylogeographical analysis of Lily symptomless virus

The complete genomic nucleotide sequence of an Indian isolate of Lily symptomless virus (LSV) was determined by sequencing 11 overlapping cDNA fragments of different sizes. The genome consisted of 8,394 nucleotides, excluding the poly (A) tail and contained six open reading frames (ORFs) coding protein for ORF1 220 kDa [1,948 amino acid (aa)], ORF2 25 kDa (228 aa), ORF3 12 kDa (106 aa), ORF4 7 kDa (64 aa), ORF5 32 kDa (291 aa) and ORF6 16 kDa (140 aa) from 5' to 3' end. Sequence was analyzed with other previously characterized full genomes of LSV. Phylogenetic analysis on the basis of RNA-dependent RNA polymerase (RdRp), Triple gene block proteins (TGB's), Coat protein (CP), and ORF6 (16 kDa protein) amino acid sequence revealed that Indian isolate is closely related to The Netherlands Isolate (AJ564638). The overall genome of the present LSV isolate shares 97-98% nucleotide sequence homology with the previously characterized isolates. The phylogenetic analysis, sequence alignment studies, and recombination detection program (RDP3) analysis provided evidence for the occurrence of recombination between the present isolate (AM422452) as major parent and The Netherlands Isolate (AJ564638) and Chinese isolate (AM263208) as minor parents in two different independent recombination events. Based on the recombination analysis, it is suggested that the 3' end of the present isolate is involved in recombination with Chinese isolate (AM263208) and gave rise to the Korean isolate. To the best of our knowledge, this is the first report of complete nucleotide sequence from India and also the first evidence of homologous recombination in LSV.

沖永良部島のテッポウユリ「ひのもと」の茎に発生した赤すじ症状の発生実態調査と血清学的検討

In 2001, a new symptom was observed on the stem of Japanese Easter lily (Lilium longiflorum Thunb. “ Hinomoto” ), which was characterized by reddish-brown streaks (“ aka-suji” in Japanese) in Okinoerabu Island, Kagoshima Prefecture, Japan. It seemed that first chlorotic stripes (“ shiro- suji” in Japanese) appeared and these later turned reddish-brown when the lily approached the flowering stage in the seasonal cycle. Double-antibody sandwich enzyme-linked immunosorbent assay (DAS-ELISA) detected Cucumber mosaic virus (CMV) and Lily symptomless virus (LSV) in lily with reddish-brown streaks. However, these 2 viruses were also detected in symptomless lily plants, indicating that additional factors might exist that induce the symptom. Further, we determined that the reddish-brown streaks were transmitted by the vegetative propagation of lilies. Taken together, these results suggested a viral etiology of the reddish-brown streaks.

Comparison of two gel filtration chromatographic methods for the purification of Lily symptomless virus

Lily symptomless virus (LSV) occurs frequently in many Lilium species worldwide and often causes developmental abnormalities such as a smaller flower and lower bulb yield. In this study, two moderate and efficient gel filtration chromatography (GFC) methods was compared, these two techniques were, respectively, based on Superdex-200 HR and Sephacryl S-1000 SF. The products purified by the two methods were then characterized by measurements with UV-spectrophotometer, reverse transcriptase (RT)-PCR, transmission electron microscope (TEM), polycrylamide gel electrophoresis (PAGE), Western blotting and matrix assisted laser desorption-ionisation/time-of-flight mass spectrometry (MALDI-TOF-MS). The final yield of purified LSV by the Superdex-200 HR GFC was 9.4 mg from 50 g of fresh infected tissues of Lanzhou lily. However, from the same amount tissues, only 5.6 mg of LSV were obtained by using Sephacryl S-1000 SF GFC. The Superdex-200 HR method was thus shown to be more suitable for the purification of LSV than the Sephacryl S-1000 SF GFC. The Superdex-200 HR method does not require costly equipment for density centrifugation and ultracentrifugation. Furthermore, it can provide an economical and efficient way to obtain purified products for the preparation of antibodies for serological diagnosis or LSV infection and related investigations.

Clonal Variability among Grower Bulb Lots of Easter Lily ‘Nellie White’

Potted Easter lily (Lilium longiflorum Thunb.) ranks among the top five potted flowering plants in the United States in economic value. One clone (‘Nellie White’) dominates the North American market. It is grown by less than 10 bulb producers, each maintaining their own propagation stock and practicing intraclonal strain selection. Greenhouse forcers attest to forcing differences depending on the bulb grower. The objective of this study was to determine the extent and sources of morphological variability among bulb growers. Bulb lots were obtained in 2002 (S1) and 2003 (S2) (n = 11 and n = 12 lots respectively) with 12 or 15 bulbs/lot. Grower's identification was confidential but kept consistent across shipment years. Bulbs were obtained as the 20.3 to 22.9-cm circumference commercial class, and S1 and S2 shipments were control temperature forced over two forcing cycles (FC1, FC2). Data collection included initial bulb weight and circumference; days to stem emergence (SEM), visible flower bud (VFB), and anthesis (AN); plant and inflorescence height; number of stems, leaves, flowers, and ovules per first flower/stem reaching AN; percentage of ovules forming viable seeds; leaf length and width; major lily viruses (presence/absence, relative optical density); leaf length-to-width ratios; AN-SEM, AN-VFB, and VFB-SEM. Significant differences were found among bulb lots for every trait except AN-VFB. Variability among bulb lots can be attributed to variation in initial bulb size, previous forcing cycle environment, variable lily symptomless virus (LSV) titer, and underlying genetic/epigenetic differences. Bulb circumference had the highest standardized canonical coefficient for canonical variable one in S2-FC1 and was a significant covariate in analysis of covariance; larger bulbs tended to produce larger plants. Forcing over two cycles allowed for less phenotypic variability among bulb lots in FC2 because of a common FC1 environment. All lilies were positive for LSV and negative for four other viruses tested. Significant negative correlations in S2 between relative optical density and plant height (FC1), initial bulb weight (FC2), and initial bulb circumference (FC2) indicate an effect of relative LSV titer on plant morphology. The role of LSV titer and genetic/epigenetic intergrower variability in ‘Nellie White’ warrants further investigation. Likewise, a lack of breeder/producer companies and the corollary independent grower strain selection has significant genetic consequences and complicates identification of superior ‘Nellie White’ clones.

Localization of lily symptomless virus and cucumber mosaic virus in anther- and filament-derived calluses and effect of callus culture duration on virus-free bulblet production in Lilium × ‘Enchantment’

Lily symptomless virus (LSV) and cucumber mosaic virus (CMV) were investigated in cultured explants of anther and filament, induced calluses, and regenerated bulblets by the enzyme-immunohistochemical method or indirect enzyme-linked immunosorbent assay (ELISA). The viruses were detected frequently in the vascular tissues of explants, anther-derived friable calluses (33% LSV; 20% CMV), filament-derived calluses (80% LSV; 60% CMV) and their regenerants but rarely in anther wall tissues, nodular calluses (10% LSV; 3% CMV) induced from anther wall tissues, and bulblets regenerated from the nodular calluses. The anther-derived nodular calluses yielded a great virus-free bulblet by 74%, as compared to 47% for anther-derived friable calluses and 35% for filament-derived calluses. Generally, the percentages of virus-free bulblets increased as the culture duration of these calluses was extended from 90–150 days. The best production of virus-free bulblets (57–100%) was achieved in 150 day-old anther-derived nodular calluses. Efficiency of virus-free bulblet production by anther culture is related to the origin and culture duration of callus in Lilium × ‘Enchantment’.

Variability in the coat protein of Lily symptomless virus isolates infecting various lily species

The coat protein sequences were characterized of Lily symptomless virus (LSV) isolates infecting Lilium longiflorum, Lilium tigrinum, Hymenocalis littoralis (spider lily) and Asiatic and Oriental hybrid lilies in India. The Indian isolates showed 78–96% homology with each other. With LSV isolates from elsewhere in the world, the Indian isolates showed 83–98% homology. The LSV‐L (L. longiflorum) and LSV‐A (Asiatic hybrid) isolates had unique stretches in the middle portion of the protein not found in other LSV isolates, even the Indian ones. The LSV gene sequence from the spider lily isolate (LSV‐S) was reported for the first time outside the Liliaceae. LSV‐S was 84–96% similar to the other Indian isolates at the protein level. The isolate infecting tiger lily (LSV‐T) was found to be different from the characterized isolates from elsewhere in the world (78–84% homology at the protein level). At the same time, LSV‐T showed much variability in the C‐terminal of the protein. A stretch of 41 amino acids in the C‐terminal was unique to this isolate. LSV‐T is proposed as a distinct isolate of LSV infecting L. tigrinum indigenous to India.

Natural occurrence of Lily symptomless virus on spider lily

During a disease survey of spider lily ( Hymenocallis littoralis, family Amaryllidaceae), in and around Palampur, Kangra Valley of Himachal Pradesh, India, plants were found with leaves that showed curling, chlorotic striping and yellowing. These symptoms were similar to those caused by Lily symptomless virus (LSV) in Lilium longiflorum (Brunt et al., 1996). To confirm the identity of the virus, plants were tested by DAS-ELISA using LSV-specific antibodies (Agdia, USA) and six out of 27 plants with symptoms tested positive. LSV infection was confirmed by RT-PCR using a primer pair specific to the 3′ terminal of the virus (Takamatsu et al., 1994). An amplicon of the expected size (approximately 900 bp) was obtained. The amplicon was cloned, sequenced (accession no. AJ780923) and sequence analysis carried out using BLAST package, version 2.2.9. Based on this partial sequence, the isolate of LSV from spider lily was found to be closely related (97% amino acid homology) to an LSV isolate in lily from the Netherlands (accession no. X15343). Lower amino acid homologies (85%) were found with a Lily latent virus isolate from Korea (accession no. AJ131812) and a LSV isolate from lily found in India (89%, unpublished, sequence submitted as accession no. AJ585052). Spider lily samples were also tested by dot-blotting (Garger et al., 1983), using the cloned LSV PCR product as a probe. Using this method, the virus was detected in nine out of 27 plants tested; with some ELISA-negative plants testing positive by dot-blot hybridization. This is the first report of the occurrence of LSV in spider lily ( Hymenocallis spp.) and in any host outside the family Liliaceae.