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

Abstract

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.

Molecular Detection and Comparative Sequence Analysis of Viruses Infecting Fig Trees in Turkey

“…Several new viruses were recently reported such as FLMaV1‐2, FMV, FLV‐1, FMMaV, AFCV1‐2, FBV‐1, FCV, but only FMV was shown to be one of the main incitants agent of FMD (Elbeaino et al. 2009a,b); its transmission by eriophyde mites was confirmed by electron microscope and molecular analyses (Çağlayan et al. 2010).…”

“…This is the first report of FCV, FBV‐1, FMMaV, AFCV‐1, AFCV‐2 and FLV‐1 occurring in fig plantations in Turkey. FMV was efficiently transmitted from diseased to healthy fig seedlings by A. ficus (Çağlayan et al. 2010) and, therefore, it can be regarded as the only causal agent of fig mosaic disease.…”

“…However, as it is well known that FMD is caused by a complex of viruses, its aetiology is still being investigated by different research groups. Although FMV was already reported in both fig plantations and experimentally inoculated fig seedlings in Turkey (Çağlayan et al. 2009a,b, 2010), new viruses associated with FMD have never been tested.…”

Rapid detection of fig mosaic virus using reverse transcription loop-mediated isothermal amplification

“…4). Compared with RT-PCR, the only method used to detect FMV so far (Ç aglayan et al 2010;Walia et al 2009), this RT-LAMP method is more practical in that reaction time can be shortened and electrophoresis can be omitted. Furthermore, a toothpick sampling method permits faster and easier detection of FMV without RNA extraction.…”

“…FMV is transmitted by the eriophyid mite Aceria ficus (Ç aglayan et al 2010;Flock and Wallace 1955), and infected fig trees exhibit mosaic, ringspot, and chlorosis and deformation of leaves (Blodgett and Gomec 1967;Ishikawa et al 2012a). Yellow spots often appear on the fruits and directly diminish the yield and quality of the fig fruits.…”