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Rhizoctonia root rot disease of common bean (Phaseolus vulgaris L.), caused by Rhizoctonia solani AG4, is one of the most important bean diseases worldwide. The use of biological and non-biological prime agents has become a promising and environmentally friendly alternative to the management of soil-borne pathogens. Therefore, the present study aimed to compare the effect of Bacillus subtilis isolate A4 (biological prime) and beta-aminobutyric acid (BABA) (non-biological prime) on the management of Rhizoctonia root rot disease in Talash and Sadri cultivars of common bean plants. The seeds were coated with the mentioned priming agents and after drying, they were planted and kept in the greenhouse at a temperature of 20±2 °C. Plants at the cotyledon stage were inoculated by R. solani AG4 inoculum. The induction of resistance in plants was evaluated by measuring disease severity, morphological, and physiological factors three weeks after inoculation. The priming factors increased almost all morphological and physiological measured traits, compared to the control. The plants treated with prime agents had a lower disease severity index (DSI) compared to the control plants and the Talash cultivar treated with B. subtilis had the lowest DSI, with a 59% reduction. The phenol content, catalase and peroxidase enzyme activities under bio-priming and chemo-priming treatments in the presence of the pathogen showed a significant increase compared to the control plants.

Micropropagation is one of the most important applications of plant tissue culture. Using the micropropagation for strawberry propagation, in addition to producing many plants, can meet the growing need for healthy and disease-free plants. In this study, the in vitro propagation of two strawberry cultivars (cvs. Paros and Pajaro) was investigated using Murashige and Skoog (MS) culture medium. In each cultivar, the effects of hormonal composition of the culture medium (1 mg l-1 BAP and 0.5 mg l-1 NAA + 0.2 mg l-1 BAP) and explant type (nodal bud and terminal bud (big and small) of runners) were studied. All explants provided from the glass greenhouse-grown plants. The in vitro cultures were subcultured three times at an interval of 30 d. The results of analysis of variance showed that the effect of explant type was significant for three studied traits (the number of plantlets per explant, the average height of plantlets per explant and the number of roots per explant). The best results for all three traits were obtained using nodal buds. Subculturing significantly increased the number of regenerated plantlets, so that in the third subculture, seven plantlets were obtained from each explant. In general, the results of the present study showed the good efficiency of in vitro culture of nodal buds for the micropropagation of two commercial strawberry cultivars, Pajaro and Paros.

Today, electrochemical biosensors are highly regarded due to their high sensitivity and accuracy in tracking target nucleic acids. On the other hand, due to the economic importance of fig trees, rapid and accurate diagnosis of its diseases, including Fig Mosaic Disease (FMD), which is one of the most important and destructive viral diseases of fig trees plays an effective role in the management and control of this disease. In this study, a novel label free electrochemical DNA-based biosensor was optimized to qualitatively and quantitatively identify the presence of FMV in the infected samples. In this regard, in order to optimize and improve the performance of the designed biosensor, the concentration parameters of the DNA probe to form self-assembled monolayers and the time required to perform the hybridization process in the biological range with the greatest impact on the DNA biosensor were investigated. According to the data of the calibration curve, the first linear range at -3 μM to 3 μM was obtained with the equation of the line y= 4.81x+34.58 and the detection coefficient (R2= 0.9967). In this research, the omtimized biosensor to detect a stable, high selective, easy and fast FMV-DNA, promises a diagnostic method with high efficiency and accuracy.

In an in silico investigation, genome sequences of three RNA viruses were identified in the crown imperial Fritillaria imperialis L. transcriptome dataset. Sequence comparison and phylogenetic analyses revealed that these three novel viruses belong to the genus Amalgavirus. They were tentatively named Crown imperial amalgavirus (CIAV), Iranian amalgavirus (IrAV), and Koohrang amalgavirus (KAV). The RNA-dependent RNA polymerases (RdRps) of CIAV, IrAV, and KAV showed 69.53%, 42.26%, and 37.46% amino acid sequence identities with the homologous RdRp of the most closely related virus, respectively, suggesting that they are novel viruses. Also, the conserved motifs of RdRp were detected in the RdRp of each CIAV, IrAV, and KAV. Genomes of both CIAV and IrAV were complete and contained two overlapping Open Reading Frames (ORFs). A + 1 programmed ribosomal frameshifting (PRF) motif, which matches the conserved amalgaviruses consensus sequence UUU_CGN was found at the ORF1/ORF2 boundary of CIAV and IrAV. The current study reports three novel viruses for the first time from crown imperial, and these findings enrich our understanding of new plant dsRNA virus species, which may also be helpful for the study of amalgaviruses.

Iris yellow spot virus (IYSV) is a member of the Eurasian phylogenetic group of the genus Orthotospovirus. Similar to other species in the genus, the viral particles contain three genomic fragments: small (S), medium (M), and large (L) RNAs. In the present study, the complete nucleotide sequence of the small fragment (S) RNA of two IYSV isolates from leek (Allium ampeloprasum ) (IYSV-Le1M) and onion (A. cepa) (IYSV-O2K) and the non-structural gene of the M RNA of the IYSV-Le1M isolate were determined. The results showed that based on nucleocapsid (N), small (NSs), and medium (NSm) RNA fragment non-structural genes, the isolates of Markazi Province are more closely related to each other than other IYSV isolates. However, the intergenic region (IGR) of the two isolates showed significant structural differences compared to other sequenced IYSV isolates. The IGR of the IYSV-Le1M isolate was longer than those of other IYSV isolates studied, while, for IYSV-O2K isolate, it was 440 nucleotides shorter. It was also found that for Indian and Dutch IYSV isolates, the IGR was 31 and 22 nucleotides shorter than that in the IYSV-Le1M isolate. These findings provide new information about the genetic diversity and phylogeny of IYSV isolates.

Green basil (Ocimum basilicum L.) is a medicinal plant widely used in the food, cosmetics, and perfumery industries. Cucumber mosaic virus is one of the most common plant pathogens worldwide. In the present study, the effect of cucumber mosaic virus (strain Fny) infection on the phytochemical and physiological properties of three green basil cultivars under growth chamber conditions (21 ± 2 ° C and 16-hour light/8 hour dark period) was investigated. The plants were mechanically-inoculated in the true two-leaf stage with the virus. Mean comparison of the studied traits showed that the virus significantly reduced photosynthesis, the content of chlorophyll a and b, total chlorophyll, and total carbohydrates in the infected plants. In contrast, the content of total protein, amino acid proline, total phenol, flavonoids, and the percentage of essential oils (w/v) in infected plants was increased. The results of essential oil analysis of three basil cultivars by Gas chromatography and Gas chromatography-mass showed a significant difference in essential oil compounds between control and viral treatments of each cultivar. The compounds Camphor, Carvone, Estragole, Methyl Eugenol, Beta-caryophyllene Alpha bisabolene, and Caryophyllene oxide make up more than 70% of the essential oil content. Results of the present study indicated that viral infection causes physiological and phytochemical changes in virus-infected plants. Increasing and/or decreasing the phytochemical content and some essential oil compounds depends on the interaction of the virus and the basil cultivar and may be in line with the susceptibility or resistance of the cultivars to the virus infection.

Plant infections to several pathogens at a same time are expected in nature. In most cases, plant mixed infections with viruses and fungi could result in increased susceptibility in plant host. In the present study, the interaction between turnip mosaic virus or cauliflower mosaic virus with Phoma lingam in canola (Brassica napus L.) was investigated. Experiments were carried out using a completely randomized design. Plants were mechanically inoculated with virus-infected turnip leave saps and by medium plug of fungal causal agent. To evaluate the interactions, in addition to recording the type and severity of symptoms, enzymatic (catalase and guaiacol peroxidase) and non-enzymatic (carotenoids and flavonoids) defense responses of treated plants were measured. The results showed that the severity of Phoma symptoms significantly increased in primary infection with turnip mosaic virus and then phoma inoculation, but no significant changes of Phoma symptoms were observed in initial infection with cauliflower mosaic virus. All treatments infected with case studied pathogens compared to the control treatment (no pathogen infection) showed a significant decrease in chlorophyll content, quantity of carotenoids, and flavonoids. While, catalase and guaiacol peroxidase content in the treatments infected with case studied pathogens showed a significant increase compared to the control treatment. Due to the synergistic effect of Phoma lingam and turnip mosaic virus in mixed infection of canola and reporting the incidence of both causal agents in canola cultivated areas in Iran, it is recommended to select canola cultivars that are resistant to both pathogens.

Mixed infections of plants with viruses is a common phenomenon occurring in nature. In the present study, interactions between Beet curly top virus (BCTV-Svr), Beet curly top Iran virus (BCTIV) and Cucumber mosaic virus (CMV) were investigated in resistant cultivar (BST853) of sugar beet (Beta vulgaris) to curly top disease at 20°C and 26 °C; pepper (California Wander cultivar) and bean (Akhtar and Goli cultivars) at 26 °C. Experiments were performed in a completely randomized design. Plants were inoculated with infectious clones of BCTV-Svr and BCTIV and also mechanically with the sap of the Fars isolate of CMV infected Cucumis sp. leaves. The intensity of the bands of PCR products was evaluated by Totallab software. The viruses did not induce any symptoms at 20 ± 1 °C on sugar beet plants, except vein clearing observed in some treatments. In the case of BCTV-Svr + CMV and BCTV-Svr + BCTIV treatments, plants showed symptoms one week earlier than single infection treatments at 26 ± 1 °C. Similar results were obtained in treatments using pepper and bean plants. Analysis of PCR data showed that BCTV-Svr accumulation in BCTV-Svr + CMV and BCTIV + BCTV-Svr treatments increased compared to single treatment of the virus. Results of this study showed that co-infection of BCTV-Svr and BCTIV with CMV leads to breakdown of resistance and induction of severe symptoms in sugar beet, pepper and bean plants. Hence, it seems that the host plant, does not affect interaction of these viruses.

Curly top is one of the most important viral diseases of sugar beet. Use of resistance sources is a promising strategy for control of this disease. In the present study, the efficiency of four gene silencing constructs (OUT-hp، IN-hp، sense and antisense) against two major causes of curly top disease in Iran, beet curly top virus-Svr (BCTV) and beet curly top Iran virus (BCTIV), were evaluated in transgenic plants. Selection of transgenic plant seeds was carried out on selective medium 1/2MS containing glufosinate-ammonium (Basta) and the results showed that the pBCTV-IN-hp construct resulted in the highest germinated seeds. Selected plants were transferred to greenhouse and evaluated for resistance to basta and detection of silencing constructs in the transgenic plants. Afterwards, resistance of the selected transgenic plants to beet curly top viruses and resistance stability against cucumber mosaic virus (CMV) was evaluated in a completely randomized design with six treatments in a factorial experiment. The results showed that the transformed lines with each of four constructs were significantly different in severity of symptoms, plant height and number of flowering stems compared to their respective controls. Although these transgenic plants were resistant to BCTV-Svr and BCTIV, in their challenge inoculation experiments it was shown that this resistance was suppressed by CMV infection. 

To assess the variability of Macrophomina phaseolina (Tassi) Goid, the causal agent of charcoal rot of Sesame, sixty isolates recovered from ten geographic regions, were analyzed using inter simple sequence repeat (ISSR) and universal rice primer (URP) markers. Isolates were grouped into eight clusters at 78% genetic similarity level. Our results showed that the five ISSR primers produced 105 bands of which 77.11% were polymorphic and eight URP-PCR primers generated 135 bands of which 66.84% were polymorphic. These methods showed a considerable genetic diversity among Iranian isolates, but no correlation was found between genetic diversity and geographical origins of the isolates. Analysis of molecular variance revealed that a large proportion of genetic variability resulted from the differences among isolates within regions. The findings of this study demonstrated that the low-genetic differentiation (GST) and high gene flow (Nm) among populations had a significant effect on the emergence and evolutionary development of M. phaseolina.

 High level expression of recombinant protein in Escherichia coli often results in aggregation of the expressed protein molecules into inclusion bodies. Cysteines in the protein contribute to this process. Intermolecular and intramolecular disulfide bonds formation in Grapevine fanleaf virus (GFLV)-coat protein (CP), a cysteine-rich protein, and lead to aggregation when the recombinant protein was overexpressed in E. coli. Hence, aggregated proteins should be solubilized and allowed to refold to obtain native- or correctly- folded recombinant proteins.   In this paper, SDS/MPD method used as a unique approach to refold the structure some protein in the presence of the denaturing agent, Sodium Dodecyl Sulfate (SDS). This was made possible by addition of the amphipathic solvent 2,4-Methyl-2-PentaneDiol (MPD), used as protecting but also as refolding agent for these proteins. For this purpose, the inclusion bodies containing insoluble proteins of GFLV CP were solubilized by denaturing with SDS, then the soluble proteins were purified by the size exclusion chromatography, and finally, the purified proteins were refolded using SDS/MPD method.   Transmission electron microscopy images confirmed the reassembly GFLV VLPs using SDS/MPD method.   MPD modulate the denaturing properties of SDS, therefore, for the first time, a simple and effective method to refolded GFLV VLP from the SDS-denatured state.

Turnip mosaic virus (TuMV) has frequently been reported from canola fields. Cultivation of resistant varieties is the best method to control viral diseases. However, plants that are resistant to a virus may lose their resistance in co-infection with other viruses. Therefore, in the present study the effect of mixed infection of TuMV with Cucumber mosaic virus (CMV) and Cauliflower mosaic virus (CaMV) on the resistance of a tolerant canola cultivar (Karaj 3) and a transgenic canola of RGS003spring variety with hairpin construct and high resistance to TuMV was investigated under greenhouse conditions. Canola plants were inoculated mechanically and then, relative TuMV content was assayed by semi-quantitative RT-PCR. Results demonstrated that mixed infection of TuMV and CaMV did not affect the resistance of transgenic canola plants against TuMV. Also, there was not any significant difference in TuMV content in the presence of CaMV. However, synergistic interaction between TuMV and CMV could overcome the resistance of canola plants to TuMV. The result of semi-quantitative RT-PCR indicated that TuMV accumulation was enhanced in the presence of CMV in transgenic plants, whereas TuMV levels were not affected by co-infection with CMV in Karaj 3. Therefore, it is concluded that for the introduction of TuMV-resistant transgenic plants, it is necessary to design a construct that the resulting transgenic plants would also be resistant to CMVsimultaneously.

Molecular responses of susceptible (Marfona) and tolerant (Els) cultivars of Solanum tuberosum, and a resistant genotype of S. phureja were comparatively studied using a cDNA-AFLP technique to identify candidate genes involved in defense mechanisms against Ralstonia solanacearum. Transcriptional changes were studied at 0, 2, 4 and 7 days post inoculation of the plants by R. solanacearum through root inoculation under in vitro conditions. Of the 2820 transcript derived fragments (TDFs) detected, 206 TDFs showed variable patterns. In total 20 TDFs with stronger differential induction were sequenced. These TDFs showed significant homologies with the genes involved in physiological processes, stress responses, cell structure, defense, transcription and protein synthesis/folding. Approximately 5% of the sequenced TDFs were identified with unknown function. Induction of a higher number of genes was altered in response to R. solanacearum in S. phureja compared to S. tuberosum.

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.

Crown gall is one of the most destructive bacterial diseases of plants. Nowadays, special attention has been focused on the biological control of plant diseases as an alternative to chemical control. This study was conducted to better understanding the molecular mechanism of Surfactin on Agrobacterium tumefaciens as a prerequisite for the use of Bacillus as a biocontrol agent of this pathogen. In this study, Tobacco plants (Nicotiana tabacum), IBRC-M10701 strains of A. tumefaciens, and pure commercial Surfactin (25 µm) were used. miRNAs and lox genes have an important effect in the auxin signalling pathway. Using Real-time PCR, the expression level of miR167 and lox gene measured 1, 3, and 6 days after inoculations in the interaction of A. tumifaciens IBRC-M10701 and Surfactin. The expression level of lox gene in Agrobacterium treatment showed 0.47, 22.9, and 61.8 increased. In Surfactin treatment it was 4.6, 3.6 and, 11.6 fold and in Surfactin-Agrobacterium treatment this amount was 4.2, 38.8, and 20.3 fold. In addition, the expression level of nta-miRNA167 in Agrobacterium treatment indicated an increase of 3.4 and 214.4 fold (in the first and third day after inoculation), then decreased to 2.5 fold (in the sixth day), in treatment with Surfactin the amount of expression level was detected as 3.2, 13.2 and 4.5 fold and in Surfactin-Agrobacterium treatment this amount was 1.6, 2.2 and 9.6 fold compared with the control. All of the results indicated the positive effect of Surfactin in suppression the strain IBRC-M10701 of Agrobacterium. The results indicated the key role of Surfactin in biocontrol which reflected the possible use of Bacillus strains producing Surfactin in biological control.

Fig mosaic disease which is known as one of the most important impacting viral diseases of fig, is caused by several DNA and RNA viruses belonging to the different genera and families. The objective of the present study was to evaluate the presence of the most important RNA viral agents causing the disease including: Fig mosaic virus (FMV), Fig latent virus-1 (FLV-1), Fig cryptic virus (FCV), Fig fleck-associated virus (FFKaV), Fig leaf mottle associated virus-1 (FLMaV-1), Fig leaf mottle associated virus-2 (FLMaV-2), Fig leaf mottle associated virus-3 (FLMaV-3) and Fig mild mottle associated virus (FMMaV) in different fig cultivations of the country. Sample collection was done from 14 provinces and 611 symptomatic fig leaves. The cDNA of the samples was synthesized using the isolated dsRNAs with cellulose column and random primer. The molecular identification was performed using PCR and specific primers for each virus. After characterization of the infected regions, the results of identification of mixed infections by different viruses showed that the FMV. The results indicated that all of the studied provinces and more than half of the collected samples are infected with at least one of the viruses. Some of the viruses such as FMV were not detected in certain visited regions such as Fars province. The FMV and FFKaV with infection rates of 34.7% and 14.2% and FMMaV with 4.4% showed the highest and lowest infection rates, respectively. The highest level of the mixed infection was observed for FMV and the members of the Closteroviridae family.

Members of the genus Orthotospovirus cause serious diseases in a variety of economically important crops, including ornamentals and vegetables, worldwide. To detect the orthotospoviruses infecting different crops and ornamental plants in Markazi province, Iran, about 160 suspected samples with viral-like symptoms were collected. Totally 106 of the specimens showed positive reaction in DAS-LEISA test using polyclonal antibodies raised against N proteins of Tomato yellow ring virus (TYRV), Iris yellow spot virus (IYSV) and Groundnut bud necrosis virus (GBNV). Sequence analysis of the obtained fragments from RT-PCR using generic primers of Asian and Eurasian clades of tospoviruses and nucleocapsid gene specific primers confirmed the occurrence of TYRV on alstroemeria, tobacco, tomato and nasturtium; IYSV on onion and leek and Capsicum chlorosis virus (CaCV) on black-eyed susan (Rudbeckia sp.). Biological analysis of selected isolates of orthotospoviruses on Nicotiana benthamiana, Capsicum annuum and Vigna unguiculata showed that TYRV isolates were differentiated from each other. Phylogenetic analysis based on amino acid sequences of nucleocapsid protein indicated that TYRV isolates belong to TYRV-t strain and IYSV isolates belong to Eurasia-IYSV cluster. In addition, CaCV isolates were grouped into Watermelon silver mottle virus (WSMoV) clade with close relationship with the United State CaCV isolate.

Due to the wide applications of gold nanoparticles, there have been great demands for their synthesis recently. Chemical methods produce pure and Non-dispersive nanoparticles, but these are quite expensive and potentially toxic to the environment. It has been suggested that the use of biological organisms and their components could be a suitable alternative for the production of nanoparticle in an eco-friendly manner (green synthesis). Using plant extracts for nanoparticle synthesis can be advantageous over other biological processes because it eliminates the elaborate process of maintaining cell cultures and can also be suitably scaled up for large-scale synthesis. In this study leaf extracts of Water cress, were used for green synthesis of gold nanoparticles. Gold nanoparticles were formed by treating an aqueous HAuCl4 solution by different amount of plant leaf extract as reducing agent at different temperatures. UV–visible spectroscopy was used for monitoring of the reaction progress. The synthesized gold nanoparticles were characterized with Dynamic light scattering (DLS) size analyzer, Transmission electron microscopy (TEM) and Fourier-transform infrared spectroscopy (FTIR). The results show that only a few minutes were required for the synthesis of gold nanoparticles at 60 °C and 80 °C by 1000 μl of plant extract, suggesting appropriate reaction rates in comparable to those of nanoparticle synthesis by chemical methods. TEM images showed that spherical nanoparticles (size, 10–50 nm) were obtained at higher temperatures and leaf broth concentrations. The analysis of FTIR bands show that the Polysaccharides and proteins are probably involved in the bio reduction and synthesis of nanoparticles.

Fig mosaic disease is considered as the most common fig viral disease, which occurs worldwide. Fig badnavirus-1 (FBV-1) is one of the most important viruses involved in this viral disease. In the present research, phylogenetic relationship between the Iranian and other detected FBV-1 isolates was studied. A genomic fragment with an expected size about 1090 bp was amplified from the movement protein coding region of twelve virus isolates using specific primers. Amplified fragments were cloned in plasmid pTZ57R/T, and sequenced. Obtained sequences were phylogenetically compared with the corresponding isolates available in the GenBank after multiple alignments. The phylogenetic tree was drawn for the FBV-1 isolates based on the movement protein gene sequence. The studied isolates were categorized into two distinct phylogroups in which Iranian isolates were separated into two different subgroups in group I with 99% identity at the nucleotide level. Phylogeny on the basis of the amino acid sequences categorized isolates with 98-99٪ identity into three different groups. According to the results of this study, it could be concluded that genetic variation between Iranian isolates is less than that of American isolates, and additionally the genetic variation between the isolates is affected by the geographical condition.

In this study incidence of Beet mosaic virus (BtMV) was assessed in sugar beet fields in Razavi Khorasan, North Khorasan and Alborz provinces and to perform phylogenetic analysis of Iranian BtMV isolates and to study the phylogenetic relationship among them with other reported BtMV isolates, a part of the viral genome consists of NIb and coat protein genes was sequenced. To do this, RNA was extracted from ELISA positive samples and Reverse Transcriptase Polymerase Chain Reaction (RT-PCR) was performed by specific designed primers and amplified DNA fragments were cloned in PTZ57R / T plasmid and sequenced. The NIb and coat protein (CP) were aligned with other sequences available in GenBank. Then, percent equity matrix and evolutionary parameters were obtained. Phylogenetic tree was drawn and recombination analyses were performed. Based on the phylogenetic tree, BtMV isolates were divided into two groups, China, Slovakia and Australia (Euroasia) isolates were placed in a same group and American isolate was located in another group. Results showed that the Iranian isolates were placed in a separate cluster in the Euroasia group. This is the first report of partial sequence of Iranian BtMV genome.

Over the past 40 years, there has been a re-orientation of virology studies toward the beneficial use of viruses, and several plant viruses have been employed as expression vectors. The use of plant virus vectors for production of recombinant proteins has advantages such as speed of expression, high yield, reduced cost and duration of studies, and an extremely high throughput of recombinant proteins. Thus with such vectors large scale production of recombinant proteins required for pharmaceutical and industrial applications is accessible. Plant viruses can also also be used for improved vaccine efficacy. Such vaccines can be made by ligand conjugation of a non-immunogenic peptide to the outer surface of the virus coat protein. Finally, plant virus vectors can be employed as library construction tools for discovery of gene function in genomics studies. Here, we review the use of plant viruses in expression of recombinant proteins.

The expanding cultivation of canola (Brassica napus L.) in the world indicates the importance of this plant. Out of 12 reported viruses in canola, Cauliflower mosaic virus (CaMV) and Turnip mosaic virus (TuMV) are of particular importance. Use of resistant cultivars would be the best approach to control losses caused by viral diseases. So far, the reaction of commercial canola cultivars in Iran to CaMV has not been assessed. In this study, 13 commercial varieties of canola were evaluated against a CaMV isolate under greenhouse condition. Analysis of symptom severity index and enzyme-linked immunosorbent assay (ELISA) of inoculated plants showed that Karaj3 cultivar was tolerant to this virus. In addition, due to co-infection of canola fields with CaMV and TuMV, the reaction of commercial canola cultivars to mixed infections with both viruses was evaluated. The obtained results showed that commercial canola cultivars in Iran were susceptible to both CaMV and TuMV. However, Karaj3 cultivar was considered to be moderately susceptible to CaMV and TuMV co-infection compared to other tested cultivars.

Fig badnavirus-1, a species of the genus Badnavirus in the family Caulimoviridae, is one the most prevalent viruses associated with the fig mosaic disease through in fig plantations worldwide. During the growing seasons of the year 2012-2013, a total of 392 asymptomatic and symptomatic leaf samples were collected from different fig orchards located in 9 provinces of Iran. Using the DIBA serological test and universal serum, samples were tested for the presence of fig mosaic disease. Following total DNA extraction from infected samples, an amplicon with a size about 1055bp was amplified using specific primer for FBV-1 protease gene. RFLP test was conducted with the PCR products of the FBV-1 infected samples and EcoRI enzyme to assess the genetic variation of infected isolates. Protease gene of nine representative FBV-1 samples from different provinces were sequenced and submitted in GenBank under the accession numbers KU314932-40. Blast analysis showed 98-99% identity between the Iranian isolates at the nucleotide and amino acid levels. Phylogenetic analysis on the basis of the nucleotide sequences of studied isolates categorized them into two different groups in which Iranian isolates grouped together in a separate group distinct from American isolate. Phylogeny on the basis of the amino acid sequence revealed a different phylogenetic tree. Totally, results of this study indicated the presence of different FBV-1 populations in Iran.

Quality of DNA is usually determined by multiple factors such as pollution especially caused by RNA, protein, lipid and other structures that inhibit Taq polymerase enzyme in polymerase chain reaction (PCR) and inhibit the cutting enzymes. The existence of phenolic compounds and other secondary metabolites has many effects on the quantity and quality of the purified DNA. At this investigation, in terms of quality and quantity with an efficient method for purification of DNA from S. marianum L. plant leaves, taking into account existing limitations to be provided.
Subjects and

In this study quantitative and qualitative comparison between two DNA extraction methods namely sodium dodecyl sulfate (SDS) and a modified cetyl trimethylammonium bromide (CTAB), were undertaken. The quantity of extracted DNA was determined by measurement of the absorption rate in wavelengths of 260 and 280 nm and their ratios by spectrophotometer. For investigate DNA quality the existence of RNA fracture was evaluated by agarose gel.

In terms of quantity and quality, for DNA extraction from S. marianum Populations, CTAB method had low performance While, SDS method showed appropriate performance in terms of quantity, quality and purity of extracted DNA.

ANOVA of samples revealed that the purification method, races and their interaction is very significant and showed that the purification of the races and their interaction had an impact on the quality of purified DNA. The 280A/260A ratio that is more than 2 indicates the presence of RNA and DNA degradation. Also if this ratio is less than 1.8 Indicating the presence of protein contamination in DNA. In genetic engineering researches and genetic studies, the suitable methods for DNA purifying are those that get higher quantity and quality of net DNA. Many studies carried out on medicinal plants and plants which contain high level of polyphenol and polysaccharide compounds showed that CTAB method and other methods that are technically same to CTAB have better efficiency. CTAB as a detergent can form complex with the DNA and can separate it from carbohydrates and proteins. The remaining polysaccharides are removed by concentrated NaCl. Keywords: DNA extraction, DNA quantity and quality, CTAB method, SDS method, Medicinal plant, Silybum marianum, PCR. ►Please cite this paper as: Hoseini SA, Shams Bakhsh M, Alami Saeed Kh, Hedayat Manesh Z, Heidari A. Quantitative and Qualitative Comparison of CTAB and SDS Method for DNA Extraction from the Herb Milk Thistle (Silybum marianum L.).