Fig Mosaic Virus Research Articles

First report of fig mosaic virus infecting common fig (Ficus carica) in Japan

For the first time, fig mosaic virus (FMV) was detected in common fig (Ficus carica) trees in Shimane, Japan. These trees exhibited mosaic, ringspots, or distortion, accompanied by chlorosis on leaves and yellow spots on fruits. Some of the symptomatic trees were infested with the eriophyid mite Aceria ficus. The virus was detected based on RT-PCR, followed by sequencing. The amplified 300 base-pair fragments shared 83.5–91.5% identity with the corresponding region of RNA-dependent RNA polymerase gene of FMV isolates previously reported in Turkey, Iran, and Italy.

Incidence of Fig Leaf Mottle-associated Virus and Fig Mosaic Virus in Eastern Province of Saudi Arabia

Incidence of Fig Leaf Mottle-associated Virus and Fig Mosaic Virus in Eastern Province of Saudi Arabia

Viruses infecting figs in Egypt

Fig production in Egypt is in continuous decline because many diseases, particularly those caused by viruses, are compromising this crop. RT-PCR assays were conducted on 60 fig samples collected from three Egyptian fig-growing provinces (Ismailia, Qena and North Sinai), from the three main fig varieties (cvs. Sultany, Abode and El-Adasy), to investigate the presence of Fig leaf mottle-associated virus 1 (FLMaV-1), Fig leaf mottle-associated virus 2 (FLMaV-2), Fig mild mottle-associated virus (FMMaV) and Fig mosaic virus (FMV). The overall average incidence of infection reached 90%, with a peak of 95% in Ismailia province. All four viruses were detected in tested samples, with infection rates of 68.3% for FLMaV-1, 35% for FLMaV-2, 28.3% for FMMaV and 46.7% for FMV. This is the first report of the presence of these viruses in Egypt and offers a preliminary insight on the unsatisfactory sanitary status of fig in this country.

SURVEY OF FIG VIRUSES IN THE CANARY ISLANDS

SUMMARY A survey for viruses was carried out in the main figgrowing areas of the Canary Islands in 2010. A total of 30 samples were collected and checked by RT-PCR for the presence of Fig mosaic virus (FMV), Fig leaf mottleassociated virus 1 (FLMaV-1), Fig leaf mottle-associated virus 2 (FLMaV-2), Fig mild mottling-associated virus (FMMaV) and Fig latent virus 1 (FLV-1) using virusspecific primers. Approximately 90% of the trees were infected by at least one virus, with mixed infections in ca. 67% of the samples. FLMaV-1 and FMV were the prevailing viruses as they were found in 53.3% and 50% of the samples, respectively. Equally significant was the infection rate of the other three viruses investigated. Mosaic symptoms were consistently observed in most FMV-infected fig trees (43%). Few trees with mosaic symptoms (17%), however, were RT-PCR negative for FMV. These trees were mix-infected with most of the other tested viruses.

Comparison by Sequence-Based and Electron Microscopic Analyses of Fig mosaic virus Isolates Obtained from Field and Experimentally Inoculated Fig Plants.

Fig mosaic disease (FMD) and the fig mite, Aceria ficus, are widespread in different fig growing provinces of Turkey. Fig trees (Ficus carica) cv. Bursa siyahı (D1) and an unknown seedling (D2) that showed typical FMD symptoms and was heavily infested by fig mites were used as donor plants for attempted mite transmissions to healthy fig seedlings. Transmission electron microscopy observations of donor plant samples prior to the transmission tests were performed and showed the presence of double membrane bodies (DMBs) in the palisade mesophyll cells. Electron microscopy of all experimentally inoculated fig seedlings showed the same bodies. This result reinforced the suggestion that an agent that elicits the production of DMBs in infected cells is involved in the etiology of FMD. Double-stranded (ds)RNA analyses were also performed from experimentally inoculated plants, and dsRNAs with sizes approximately 1.30 and 1.96 kb were obtained. Reverse transcription-polymerase chain reaction (RT-PCR) products of 468 and 298 bp specific to Fig mosaic virus (FMV) were amplified from both donor and experimentally inoculated plants. BLAST analyses of nucleotide sequences of these fragments showed 90% identity with FMV for the donor plant and 94 to 96% for experimentally inoculated plants. According to these results, FMV is present in both donor and experimentally inoculated plants in Turkey, and this virus is transmissible by A. ficus from fig plant to fig plant.

The Prevalence of Three Viruses Infecting Fig in Southern Turkey

In a survey of four fig-growing provinces of Turkey (Adana, Hatay, Sanliurfa and Mersin), 132 samples were tested by reverse transcription-polymerase chain reaction (RT-PCR) to assess the presence of Fig leaf mottle-associated virus 1 (FLMaV-1), Fig leaf mottle-associated virus 2 (FLMaV-2) and Fig mosaic virus (FMV). All samples were negative in PCR to FLMaV-1, whereas FLMaV-2 and FMV were detected in six (4.5%) and 10 (7.6%) of the samples, respectively. Both viruses were found in fig trees collected in the provinces of Adana, Hatay and Sanliurfa, but no infection was found in Mersin province. Sequence analysis of amplified DNA showed a level of nucleotides variability ranging from 1 to 10% for FLMaV-2 and from 6 to 17% for FMV isolates. Phylogenetic analysis grouped the Turkish FLMaV-2 isolates in one cluster together with other near-eastern FLMaV-2 isolates previously reported in GenBank.

Complete nucleotide sequence of four RNA segments of fig mosaic virus

The complete sequence of four viral RNA segments of fig mosaic virus (FMV) was determined. Each of the four RNAs comprises a single open reading frame (ORF) 7,093, 2,252, 1,490 and 1,472 nucleotides in size, respectively. These ORFs encode the following proteins in the order: RNA-dependent RNA polymerase (p1 264 kDa), a putative glycoprotein (p2 73 kDa), a putative nucleocapsid protein (p3 35 kDa) and a protein with unknown function (p4 40.5 kDa). All RNA segments possess untranslated regions containing at the 5' and 3' termini a 13-nt complementary sequence. A conserved motif denoted premotif A was found to be present in addition to the five RdRp motifs A-F in RNA-1. In phylogenetic trees constructed with the amino acid sequences of RNA-1 and RNA-2, FMV clustered consistently with European mountain ash ringspot-associated virus (EMARaV) in a clade close to those comprising members of the genera Hantavirus, Orthobunyavirus and Tospovirus. The amino acid sequence of the putative FMV nucleocapsid protein encoded by RNA-3 shared identity with comparable sequences of EMARaV and the unclassified viruses pigeonpea sterility mosaic virus (PPSMV) and maize red stripe virus (MRSV). The nucleocapsid sequences rooted the four viruses in a clade close to the genus Tospovirus. Based on molecular, morphological and epidemiological features, FMV appears to be very closely related to PPSMV and MRSV. All these viruses are phylogenetically related to EMARaV and therefore seem to be eligible for classification in the proposed genus Emaravirus, which, in turn, may find a taxonomic allocation in the family Bunyaviridae.

A multipartite single-stranded negative-sense RNA virus is the putative agent of fig mosaic disease

Several dsRNA bands (approx. 0.6-7 kbp in size) were recovered from tissues of mosaic-diseased fig seedlings which contained the enveloped round structures known as double membrane bodies (DMBs). blast analysis of a 4353 and a 1120 nt sequence from the two largest RNA segments showed homology with the polymerase and the putative glycoprotein precursor genes of negative-sense single-stranded RNA viruses of the family Bunyaviridae. Negative- and positive-sense riboprobes designed from both RNA segments hybridized to two bands of approximately 7 and 2.3 kbp in Northern blots of dsRNAs. Thus, these segments were identified as putative RNA-1 and RNA-2 of a novel virus for which the name fig mosaic virus (FMV) is proposed. Identity levels of predicted amino acids of the protein encoded by FMV RNA-1 with those of species of the family Bunyaviridae and European mountain ash ringspot-associated virus (EMERaV) were 28 and 54 %, respectively. RNA-2 showed 38 % identity at the amino acid level only with EMARaV. RNA-1 segment contained five conserved motifs (A-E) and an endonucleolytic centre of comparable genes of L RNA of bunyaviruses and EMARaV RNA-1. In a phylogenetic tree constructed with RdRp sequences, EMARaV grouped with FMV in a clade distinct from those of all bunyavirus genera. The consistent association of DMBs with mosaic symptoms and the results of molecular investigations strongly indicate that DMBs are particles of FMV, the aetiological agent of fig mosaic disease.

Meristem culture of two fig cultivars in Turkey

Meristem culture of two fig cultivars in Turkey. Abstract -- Introduction. Two Turkish fig cultivars, Alkuden and Bursa Siyahi, were propa- gated by meristem culture to eliminate the fig mosaic virus. The technique of dsRNA analysis was conducted on the in vitro propagated plants to test for virus-free status. Materials and methods. Four different Murashige and Skoog (MS) media complemented with different concentrations of growth hormones (GA3, BA and IBA) were compared to study the cultured meristems' survival rate, shoot formation and rooting. Short- and long-term thermotherapy treatments were also applied. Results. For survival rate, 0.2 mg GA3·L -1 + 0.5 mg BA·L -1 gave the most favorable results; for shoot formation, it was the medium with 0.2 mg GA3·L -1 + 2.0 mg BA·L -1 which was the best, while rooting rate was the highest for meristems cultured on MS medium with only 0.1 mg GA3·L -1 . Conclusion. Meristem culture, together with ther- motherapy treatment, is recommended to obtain virus-free fig plant material. Although cultu- red plants seemed to be very healthy, dsRNA virus tests are recommended for sensitive evaluation of the sanitary status of the plants obtained. Turkey / Ficus carica / micropropagation / meristem culture / plant growth substances / heat therapy / plant viruses

Micropropagation of Ficus carica L.

Abstract Many plant species now can be propagated successfully through tissue culture. In vitro work with figs has been restricted to attempts to enlongate single shoot tips to obtain plants free of fig mosaic virus (3). The present work was undertaken to develop a method for rapid propagation of Ficus carica L. ‘Kalamon’ to overcome supply problems for high density fig orchards.

In Vitro Propagation of Fig through Shoot Tip Culture1

Abstract Shoot tips excised from cultivars of Ficus carica L. with symptoms of fig mosaic virus, on Murashige and Skoog (MS) medium supplemented with 0.18 mg/liter naphthaleneacetic acid (NAA), 0.1 mg/liter 6-benzvlamino purine (BA) and 0.03 mg/liter gibberellic acid (G A) developed into shoots. These shoots were induced to root on MS containing 0.5 mg/liter NAA and 0.5 mg/liter indolebutyric acid (IBA) and subsequently transferred to soil, maintained in the green house, and were free of virus symptoms, even after 15 months.