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Chickpea (Cicer arietinum L.) is an important legume crop and widely cultivated in northwestern provinces of Iran. During a survey in the 2015 growing season a total of 170 selected chickpea plants with general yellowing symptoms including stunting and leaf bronzing were collected. Serological Elisa and tissue blot immunoassay (TIBA) tests revealed the presence of Bean leaf roll virus (BLRV) and Chickpea chlorotic stunt virus (CpCSV) as the predominant viruses in the region. Some serologically positive samples of BLRV and CpCSV were selected and rechecked by RT-PCR. The results of amplified PCR products using a specific pair of primers towards the Cp gene region of the viruses were approximately 413 bp for CpCSV and 391 bp for BLRV. Results obtained from sequence comparison of BLRV (IR-F-Lor-5) isolate form two subgroups with eight other BLRV isolates from GeneBank indicating a high homology of 96% with isolates from Argentina, Germany, Tunisia, USA, Spain, and Colombia. An isolate from Norabad (Iran) (IR-Nor) had 98% homology with HQ840727 Libyan isolate. CpCSV sequence comparison with six other GeneBank isolates indicated 98% homology with isolates from Tunisia and Azerbaijan. The overall results of this research revealed the CpCSV and BLRV (luteoviruses) associated with the yellowing disease syndrome of chickpea crops in the surveyed region.

Cauliflower mosaic virus (CaMV) causes yield losses in plants of Brassicaceae family including canola (Brassica napus). In order to detect CaMV in canola, a total of 684 leaf samples showing various virus-like symptoms were collected in several provinces of Iran including Tehran, Ghazvin, Chaharmahal-Bakhtiari, Mazandaran, Ardabil, West Azarbayejan and Fars provinces. Using a polyclonal antiserum and DAS-ELISA method, samples were tested for the presence of CaMV. ELISA positive isolates from 7 provinces, were used for further studies. Biological diversity of CaMV isolates was evaluated by their ability to infect turnip, kohlrabi and datura. All isolates under study infected turnip, producing local lesions of different sizes and timing, whereas, no symptom was obsereved on kohlrabi and datura. Specific primers amplified an 840 bp fragment of ORF V. Phylogenetic analysis grouped all Iranian isolates and two GenBank isolates (Cabb-D/H, M10376, Xinjiang, AF140604) in one cluster, while all other CaMV isolates from GenBank formed a separate cluster. [ABSTRACT FROM AUTHOR]

Soybean mosaic virus (SMV) is an important disease in soybean and is widely distributed in northern of Iran. SMV transmitted by soybean seed and detection of it is very important for disease management. In this study, several detection methods including DAS-ELISA, indirect-ELISA, tissue-print immunoassay (TPIA) and Dot immunobinding assay (DIBA) were optimized and compared with each other to identify the virus, using polyclonal antibody. For TPIA, nitrocellulose membrane was used to imprint fresh sections of healthy and infected plant materials, and for DIBA 10 microl of extracts was doted onto nitrocellulose membranes. Both membranes were incubated 1 hour in blocking buffer, and then incubated 2 h in 1:1000 dilution of IgG-conjugate. After incubation the membranes were washed three times with PBS-T buffer for 15 min. Then the membranes were incubated in substrate solution containing NBT/BCIP. After some minutes prints or blots of infected tissues turned dark violet, whereas prints or blots of healthy ones did not show any color changes. In some cases, substrate solution was Fast red, containing 0.2M Tris-HCl buffer and 2mM MgCl2, pH = 7.8, producing red color in infected prints or blots. Both methods are simple and TPIA is rapidly and easily applicable in the field. However, TPIA had some advantages over the others. TPIA is time-saving as there is no need for conventional sap extraction and also nitrocellulose membranes used for printing can be used in the field and stored for a long time or transported to another laboratory for process. These two methods can be used routinely for detection of SMV in many samples.