Brassica napus (Canola) with mosaic symptoms from Varamin (Khaveh), was fixed on B. rapa in green house. The samples were collected and tested against TUMV by D.A.Sandwich ELISA using specific antibody (DSMZ, Braunschwieg, Germany). Mechanical inoculation of ELISA positive samples caused necrotic local lesions on Nicotiana tabacum L cv. White Burley and Chenopodium amaranticolor Coste & Reyn, systemic mosaic on- Petunia hybridia Vilm , Nicotiana glutinosa L., Brassica pepo L., Brassica rapa L., Zinnia elegans L. Purified sample of virus revealed in the sucrose density gradient. Using spectrophotometery at wave lengths of 260 nm and 280 nm the purified virus Varamin of isolate had an absorbance ratio of 1.4. Antiserum was produced by injection of purified virus to New Zealand white rabbit. Electron micrographs of negatively stained row suspension of infected plants and purified virus preparations revealed flexuous, filamentous particles. Iranian isolate virus was transmitted from TUMV– infected plants to healthy plants by Brevicorye brassica in a non– persistant manner.

Turnip mosaic virus(TUMV) is one of the most prevalent viruses of canola fields in Iran. Use of resistant varieties is the best recommended manner to control losses caused by TUMV. In this research, the reaction of 11 commercial varieties and two lines of canola (Brassica napus L.) was investigated against a Netherland TUMV isolate under greenhouse condition. The seedlings were inoculated using TUMV-infected tobacco (Nicotiana benthamiana) sap at 3-5 leaf stage and their reaction was evaluated based on symptom severity index and ELISA OD405 values at four and the mean values of fresh and dry weights of plants at seven weeks after inoculation. This study was performed in a factorial experiment and randomized complete block design with three replications and each repeat involved four experimental units for each group of inoculated and uninoculated plants. Virus-infection was confirmed by RT-PCR. In accordance with evaluated parameters, reaction of varieties to the virus was significantly different. At probability level of 5%, Karaj3 was tolerant while Karaj2 was the most susceptible, RGS003 and Karaj1 were susceptible and the rest of canola varieties/lines were moderately susceptible to TUMV. Difference of OD405 values in ELISA was meaningless among inoculated plants of canola varieties/lines. Among canola varieties/lines, only fresh and dry weights of Karaj2 line was reduced significantly in virus-infected plants. The scoring system (0 to 8) for the symptoms severity of TUMV in canola was introduced for the first time in this research.

Turnip mosaic virus (TUMV) a species of the genus Potyvirus in the family Potyviridae, is one of the most prevalent viruses of canola fields in Iran. So far, commercial resistant lines or varieties against TUMV have not been known in Iran. In this research, the possibility of inducing resistant to TUMV in transgenic canola lines carrying a short fragment of the coat protein gene of the virus was evaluated. Therefore, a 130 nucleotide fragment of TUMV coat protein gene, as sense or antisense orientations, were cloned in the pFGC5941 vector independently and then were transformed to canola cotyledonary (Hayola R-Line 401 variety) explants using Agrobacterium tumefaciens strain LBA4404. Selection and confirmation of transgenic T0 and T1 lines were carried out via PCR and glufosinate ammonium herbicide (selective marker) resistance assay under greenhouse conditions. After virus inoculation to T1 lines, resistance assay was done by the scoring system. The obtained results confirmed that transgenic lines with sense construction did not show any resistant. However, several transgenic lines with antisense construction showed a different level of resistant to TUMV including delay in symptoms appearance and a decrease in symptoms severity (0-30% of T1 progeny) or symptoms recovery (10-66% of T1 progeny). This is the first report of increased resistant against TUMV via transformation of a short viral fragment sequence with the antisense orientation in canola.

Turnip mosaic virus (TUMV), Cauliflower mosaic virus (CaMV) and Beet western yellow virus (BWYV) are considered as the most important viruses of canola, worldwide. In order to determine the distribution of these viruses in Golestan province, samples from three important canola growing areas of the province were collected during 2008 and 2009. The randomly collected samples were tested for the presence of TUMV, CaMV and BWYV through DAS-ELISA. The results revealed that canola field infection levels in 2008 with TUMV, CaMV and BWYV were at 4.5%, 2.5% and 6%, respectively. Canola field infection in 2009 with TUMV, CaMV and BWYV was at the levels of 8.33%, 1.66% and 6.33%, respectively. Data analysis showed that virus factor was significant for 2008 whereas region was the factor significant for year 2009. Furthermore, BWYV infection was confirmed through RT-PCR. It is to be mentioned that this is the first report of TUMV, CaMV and BWYV on canola in Golestan province.

Turnip mosaic virus is a member of the genus Potyvirus in the family Potyviridae and has the broadest host range in the family. In order to detect and characterize local isolates of TUMV, 175 saffron samples were collected from Birjand, Khosf and Ghaen in South Khorasan between October and November 2016. Infections with TUMV were detected by ELISA in 10. 85 percent of samples. Total RNA was extracted and subjected to RT-PCR with the virus coat protein (CP) specific primers. As a result, full-length CP gene (980 bp) was amplified from nine samples and sequenced. Phylogenetic analysis of these isolates and 30 GenBank TUMV isolates showed that six Iranian isolates fell in Asian BR group with other isolates from Iran, China and Turkey. Three Iranian isolates fell in World B group with the isolates from Canada and new Zealand. Homology matrix showed the highest similarity between SKK10 and IRNTT3 and the lowest between SKK10and AB093598 from Italy (98. 96 and 87. 2%, respectively). The phylogenetic analysis showed that TUMV isolates from saffron plant in Iran were classified in different groups; therefore, they may have derived from different ancestors. This is the first investigation of TUMV on saffron in Iran.

Background and Aims: Turnip mosaic virus (TUMV) has a wide host range and no resistant commercial canola variety to this virus has been reported in Iran. The RNA silencing mechanism was applied to consider the possibility of improvement in resistance to TUMV in spring canola, RGS003 variety. Materials and Methods: To obtain an effective construct for silencing, based on the bioinformatics analysis, a fragment containing 130 conserved nucleotide sequences of the TUMV coat protein gene was gained as targeting candidate to produce sense, antisense and hairpin constructs and assessed for resistance efficiency in a transient expression system in Nicotiana benthamiana by agroinfiltration. The development of symptoms after virus inoculation revealed that the highest efficiency can be obtained by hairpin construct. Therefore, the hairpin construct was applied for the transformation of canola RGS003 via cotyledonary explants using Agrobacterium tumefaciens LBA4404. In transgenic and nontransgenic canola plants, the infection and virus titer were assessed by ratio of detection via ELISA and real-time PCR. In addition, severity of disease symptoms was scored four weeks after inoculation with a TUMV isolate. Results: The results indicated 5-12 days delay in appearance of symptoms in transgenic plants and there was a decrease in severity of symptoms in contrast to non-transgenic plants. The increased virus concentration ratio in non-transgenic compared to transgenic plants was confirmed by qRT-PCR. The ELISA results confirmed the absence of infection on five out of six transformed plants 15 dpi. Conclusions: These preliminary results proved that transgenic canola plants containing hairpin of 130 nucleotide sequences of TUMV CP gene could resist against TUMV.

It is possible to use transgenic plants, as bioreactors, for the production of recombinant inexpensive chemicals and drug components. Transient gene expression is an appropriate alternative to stable transformation because it allows an inexpensive and rapid method for expression of recombinant proteins in plant tissues. In recent years, plant viral vectors have been increasingly developed as successful biotechnological tools for the expression of a wide range of foreign proteins in plants. Plant viruses-based vectors are useful because of the autonomous replication and the high level of gene expression in a short time. Here, we have used a vector derived from an infectious turnip mosaic virus (TUMV) for transient expression of the jellyfish green fluorescent protein (GFP), as a model heterologous protein, in radish plant. The GFP ORF was inserted between NIb and CP sites under control of CAMV35S promoter. The leaves were inoculated using surface scratch by carborundum and harvested 14 days after inoculation for analysis. The visualization of GFP fluorescence in leaf disks from inoculated plants using fluorescence microscopy demonstrated gene transformation and systemic infection. Expression of the desired protein were confirmed by RT-PCR, SDS-PAGE and Dot blotting analysis. The quantitative values of GFP in different inoculated leaves were compared by ELISA assay using an anti-GFP antibody. The results showed high level of expression of GFP protein in leaves of inoculated plants compared with wild type. The results demonstrated that the TUMV-based vector has high efficiency for the expression of the foreign protein in the radish plant. This is the first examination of TUMV-based vector in radish.