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Antibacterial activities of essential oils (EOs) of three widely used herbal elements of cinnamon (Cinnamomum verum J.Presl), eucalyptus (Eucalyptus camaldulensis Dehnh.), and thyme (Zataria multiflora Boiss.), whose antimicrobial effects are indirectly described in the old literature of Persian medicine as antiseptic agents and treatments of diseases caused by Havaye Vabaee (e.g., air-borne infectious diseases), were investigated. Antibacterial activities of the EOs were evaluated against some important Zoonosis and medicine pathogenic gram-negative (Escherichia coli, Klebsiella pneumonia, Listeria monocytogenes, and Pseudomonas aeruginosa) and gram-positive (Staphylococcus aureus, S. epidermidis, and Streptococcus pyogenes) bacteria. These pathogens cause disease in animals and humans.To this end, minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), and double-diffusion assay (DDA) tests were utilized using a microdilution method. While MIC values for cinnamon, eucalyptus, and thyme ranged between 0.25-1, 8-64, and 0.5-16 μg mL-1, respectively, the range of MBC values were 1-4, 32-256, and 2-64 μg mL-1. In DDA tests, a concentration of 0.5 μg mL-1 of the three EOs induced inhibition zones ranging between 20-35, 9-25, and 0-35 mm in diameter in the culture media of the above bacteria. Antibacterial effects of double combinations of the EOs against E. coli and S. aureus were also investigated by checkerboard test and fractional inhibitory concentration (FIC) index. Combinations of the EOs resulted in FIC index values of 1.06-2, indicating no interaction between most of the compounds combined. Our study also suggested the use of thyme oil with caution in combination with cinnamon or eucalyptus oils against E. coli because of their possible antagonistic effects (FIC index = 4).

The development of reverse transcription-polymerase chain reaction using degenerate primers against conserved regions of most potyviral genomes enabled sampling of the potyvirome. However, these assays usually involve sampling potential host plants, but identifying infected plants when they are asymptomatic is challenging, and many plants, especially wild ones, contain inhibitors to DNA amplification. We used an alternative approach which utilized aphid vectors and indicator plants to identify potyviruses capable of infecting common bean (Phaseolus vulgaris). Aphids were collected from a range of asymptomatic leguminous weeds and trees in Iran, and transferred to bean seedlings under controlled conditions. Bean plants were tested serologically for potyvirus infections four-weeks post-inoculation. The serological assay and symptomatology together indicated the presence of one potyvirus, and symptomology alone implied the presence of an unidentified virus. The partial genome of the potyvirus, encompassing the complete coat protein gene, was amplified using generic potyvirus primers. Sequence analysis of the amplicon confirmed the presence of an isolate of Wisteria vein mosaic virus (WVMV), a virus species not previously identified from Western Asia. Phylogenetic analyses of available WVMV sequences categorized them into five groups: East Asian-1 to 3, North American and World. The Iranian isolate clustered with those in the World group. Multiple sequence alignment indicated the presence of some genogroup-specific amino acid substitutions among the isolates studied. Chinese isolates were sister groups of other isolates and showed higher nucleotide distances as compared with the others, suggesting a possible Eastern-Asian origin of WVMV, the main region where Wisteria might have originated.

Six provinces of Iran were surveyed during 2012–2014 to detect potyviruses infecting common bean crops. A total of 277 leaf samples were collected from bean plants and some other legumes as well as weeds and wild legumes showing virus-like symptoms. Enzyme-linked immunosorbent assay (ELISA) using broad-spectrum potyvirus antibodies gave a positive reaction with 63 samples (22.7%). Moreover, a mixed colony of aphids (Aphis craccivora and A. fabae), collected from a locust tree plant (Robinia sp.), transmitted a potyvirus to young healthy bean plants; the infection was confirmed through serological assays. Partial nuclear inclusion b (NIb) and coat protein (CP) regions of the genomes of 19 ELISA-positive samples were amplified by reverse-transcription polymerase chain reaction (RT-PCR) using NIb and NWCIEN (or WCIEN) universal primer sets, respectively. Potyvirus species identification was confirmed by BLASTN and phylogenetic analyses followed by ELISA tests using virus-specific antibodies or biological assays. The results clearly showed the presence of Bean common mosaic virus (BCMV), Bean common mosaic necrosis virus (BCMNV), Bean yellow mosaic virus (BYMV) and Wisteria vein mosaic virus (WVMV) in the samples tested. Non-specific amplification of a Cucumovirus genome by using NIb primers was also recorded. The results showed the natural occurrence of a new potyvirus species (WVMV), and a new host for BYMV (Trifolium repens) in the mid-Eurasian region of Iran. Our findings indicate the capacity of the universal detection systems for fast and accurate detection of legume potyviruses in the country and for use in routine diagnostic assays.