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

Removal of viruses from Lebanese fig varieties using tissue culture and thermotherapy

Two Lebanese fig accessions of local varieties (Biadi and Aswad), infected by Fig leaf mottle-associated virus 1 (FLMaV-1), Fig leaf mottle-associated virus 2 (FLMaV-2) and Fig mosaic virus (FMV), were subjected to tissue culture and thermotherapy for producing virus-free plant material. The virus status of all progeny explants was assayed by RT-PCR using viruses-specific primers. The shoot tip culture technique was reliable for elimination of from 60 to 100% of fig viruses. However, stem cutting culture coupled with thermotherapy was the most effective for shoot regeneration (40% of reactive explants), while elimination of the three viruses was possible even though with lower rates of removal (from zero to 81%) were achieved. This study has indicated that FLMaV-2 is more susceptible to thermotherapy than FLMaV-1 and FMV

Four viruses infecting figs in Western Saudi Arabia

Many diseases are compromising fig production in Saudi Arabia and in particular those caused by viruses. RT-PCR assays were conducted on 80 samples collected from four fig-growing provinces in the West Mecca region of Saudi Arabia, including the Fatima, Khulais, Rabigh and Alshifa valleys. Samples consisted of leaf tissues taken from caprifig and common fig trees. The presence of Fig mosaic virus (FMV), Fig leaf mottle-associated virus 1 (FLMaV-1), Fig leaf mottle-associated virus 2 (FLMaV-2) and Fig mild mottle-associated virus (FMMaV) was assessed from the samples. RT-PCR results showed that all four viruses were present in the surveyed areas with different proportions of infection. Incidence was 69% of samples, with a peak of 80%, from the Alshifa and Fatima valleys, 60% from Rabigh and 55% from Khulais valley. FLMaV-1 was the prevailing virus (55% of samples), followed by FMV (34%), whereas FLMaV-2 (11% of samples) and FMMaV (6%) were less common. Most of the mosaic symptoms observed in surveyed fig orchards occurred with the presence of FMV. However, many other symptoms remained unexplained because of the arduous task of determining the involvement of other fig-infecting viruses with mosaic disease. This is the first report of FMMaV and FLMaV-2 in Saudi Arabia, and of FMV and FLMaV-1 in western Saudi Arabia. The virus status of this crop is probably compromised and a sanitation programme is required to produce healthy plant material in Saudi Arabia

Detection and phylogenetic analyses of fig-infecting viruses in Bosnia and Herzegovina and Montenegro

During spring 2016, a survey was carried out in Bosnian-Herzegovinian (BiH) and Montenegrin (MNE) fig orchards, germplasm collection plots and outdoor gardens, to investigate the presence of unreported fig viruses possibly present in both countries, i.e. Fig leaf mottle-associated virus 2 (FLMaV-2), Fig latent virus 1 (FLV-1), Fig cryptic virus 1 (FCV-1), Fig fleck-associated virus (FFkaV) and Fig badnavirus 1 (FBV-1); as well as those previously reported, i.e. Fig leaf mottle-associated virus 1 (FLMaV-1), Fig mild mottle-associated virus (FMMaV) and Fig mosaic emaravirus (FMV). A total of 84 fig samples (49 from BIH and 35 from MNE) were collected and tested by PCR/RT-PCR using sets of virus-specific primers. Results showed that FBV-1 was the prevailing virus with all samples (100%) infected, followed by FLMaV-1 (54%), FMV (35%), FMMaV (7%), FFkaV (6%) and FLMaV-2 (1%); whereas FLV-1 and FCV-1 were not detected. Excluding the FBV-1 detection, 35% of tested trees were infected with at least one other virus. Sequence analyses of PCR/RT-PCR fragments obtained from different viruses showed that FBV-1 was the least variable (0.9% of nucleotides divergent) compared with FLMaV-1 (15.7% sequence variation), FLMaV-2 (17.4%), FMMaV (14.9%), FMV (16.9%) and FFkaV (14.3%). Phylogenetic trees constructed with obtained sequences, together with their homologues retrieved from the Genbank database, showed distinct separation of the BiH and MNE isolates from those of different origins, in particular for FFkaV and FMV; whereas for closteroviruses (FLMaV-1, FLMaV-2 and FMMaV), there was no distinction between the isolates. This is the first report on sequence analyses of fig viruses in this geographical region, and of the presence of FBV-1 in BiH and MNE, and of FLMaV-2 and FFkaV

Viruses infecting periwinkle (Catharanthus roseus L.) in Western Saudi Arabia

Periwinkle (Catharanthus roseus L.) is an ornamental plant widely grown in the Mecca region in the Kingdom of Saudi Arabia (KSA). Different symptoms similar to those induced by viruses (mosaic, vein clearing, mottling, yellowing, flower variegation) prompted surveys in eight different regions of KSA to assess the presence of periwinkle-infecting viruses, i.e. Tomato spotted wilt virus (TSWV), Cucumber mosaic virus (CMV), Lettuce mosaic virus (LMV), Catharanthus mosaic virus (CatMV) and Catharanthus yellow mosaic virus (CYMV). Two hundred and forty leaf samples were collected from naturally infected nurseries, gardens and landscape plantings, and tested by DAS-ELISA, RT-PCR and PCR assays. Results showed that all five viruses were present in the surveyed areas, with incidence of infection reaching 58%. TSWV was the most widespread, found in 44% of samples, followed by CYMV (35%), whereas CatMV (15%), CMV (11%) and LMV (6%) were present to lesser extents. The virus incidence ranged between 43% in Rabigh to 77% in Taif. This is the first report of CYMV and CatMV in KSA, and of TSWV, LMV and CMV in periwinkle in western Saudi Arabia. The high incidence of viruses and of multiple infections in periwinkle plants endangers this crop in KSA, so a sanitation programme for eliminating virus infections is desirable

Identification of three potential insect vectors of Xylella fastidiosa in southern Italy

6openInternationalInternational coauthor/editorIn order to identify potential vectors of Xylella fastidiosa in olive orchards in Puglia (southern Italy), Hemiptera insects were collected from October to December, 2013, in olive orchards with high incidences of X. fastidiosa associated with “rapid decline” symptoms. The study focused on species in the Auchenorrhyncha (sharpshooter leafhoppers and froghoppers or spittlebugs), a group that includes known vectors of X. fastidiosa. Adults of three species, i.e. Philaenus spumarius L. (Aphrophoridae), Neophilaenus campestris Fallén (Aphrophoridae) and Euscelis lineolatus Brullé (Cicadellidae) were captured, from which total DNA was extracted and assayed by PCR using three sets of specific primers designed for X. fastidiosa detection. Results of PCR showed that 38 out of a total of 84 tested insects were positive for X. fastidiosa, i.e. eight (of 20) P. spumarius, 14 (of 18) N. campestris and 16 (of 46) E. lineolatus. PCR amplicons of the RNA polymerase sigma-70 factor gene from six specimens (two of each insect species) were sequenced. The sequences obtained were 99.3‒99.4% identical. BlastN analyses demonstrated these sequences to be similar to those of X. fastidiosa isolates from olive OL-X and OL-G reported from Puglia, whereas they displayed distant molecular identity (always less than 98%) with X. fastidiosa subspecies from other countries. The detection of X. fastidiosa in P. spumarius and, for the first time, in N. campestris and E. lineolatus (which, unlike the others, is a phloem feeder), indicates potential vectoring roles of these insects for the spread of the bacterium in Puglia. Further investigations and specific infectivity trials are required to definitively determine the roles of these insects as effective vectors of this pathogen.openElbeaino, T.; Yaseen, T.; Valentini, F.; Moussa, I.E.B.; Mazzoni, V.; D'Onghia, A.M.Elbeaino, T.; Yaseen, T.; Valentini, F.; Moussa, I.E.B.; Mazzoni, V.; D'Onghia, A.M

Taxonomy of the order Bunyavirales : second update 2018

In October 2018, the order Bunyavirales was amended by inclusion of the family Arenaviridae, abolishment of three families, creation of three new families, 19 new genera, and 14 new species, and renaming of three genera and 22 species. This article presents the updated taxonomy of the order Bunyavirales as now accepted by the International Committee on Taxonomy of Viruses (ICTV).Non peer reviewe