Keywords : PCR
Biological, serological and molecular characterization of Potato virus S isolated from potato (Solanum tuberosum L.)
journal of kerbala university,
Volume 10, Issue 1, Pages 239-249
This study was conducted to serologically, biologically and molecularly characterize the ordinary strain of Potato virus S (PVSO) isolated from different potato fields located at the James Hutton Institute (JHI), Dundee City, Scotland, U.K. Fifteen potato leaf samples with one or more disease symptoms of leaf mosaic, distortion, mottling and yellowing were collected during the 2010-2011 growing season and serologically tested by double-antibody sandwich enzyme-linked immunosorbent assay (DAS-ELISA) for six plant viruses, including Potato virus Y (PVY), Potato virus A (PVA), Potato virus V (PVV), Potato virus X (PVX), Potato leafroll virus (PLRV) and Potato virus S (PVS). ELISA results showed that 10 samples among the 15 collected samples were found to be infected with PVS.
Mechanical inoculation of Chenopodium amaranticolor plants with PVS isolates induced typical symptoms of chlorotic local lesions which later developed to necrotic lesions. No obvious symptoms were observed on the non-inoculated upper leaves of C. amaranticolor. However, the presence of the virus was confirmed, by DAS-ELISA and polymerase chain reaction (PCR), in the inoculated leaves of C. amaranticolor and no virus was detected in the non-inoculated leaves of the same plants.
Examination of the virus particles by electron microscopy (EM) showed the presence of only straight filamentous particles with a length of 650 nm and a width of 12 nm, which were similar to the reported dimensions of PVS particles. However, no other virus particles related with any other plant virus with the exception of PVS particles were observed, in the examined test samples. The results also showed that all PVS isolates obtained in this study was not transmissible by Myzus persicae and Aphis nasturtii aphids.
PCR amplification, cloning and sequencing of the coat protein (CP) and 11KDa genes of PVS isolates showed 100% pairwise nucleotide identity. Based on maximum nucleotide identity, results proposed that all of these isolates were found to be belonged to the ordinary strain of PVS (PVSO).
Effect of Dimethylsulfoxide and Betaine on duplex polymerase chain reaction of human beta-globin gene amplification
journal of kerbala university,
Volume 8, Issue 0, Pages 171-177
A variety of additives and enhancing agents can be included in PCR amplifications to increase yield, specificity and consistency of PCR products. Blood samples were collected from (35) apparently healthy individual for DNA extraction and duplex PCR amplification according to the four different PCR component set up include: 1- standard set up (without PCR additives), 2- standard PCR set up plus 5% DMSO, 3- standard PCR set up plus 1M betaine, and 4- standard PCR set up plus 5% DMSO and 1M betaine. The results revealed that the standard optimization condition of duplex PCR amplification is enough to reveal a good PCR amplification of human beta-globin gene, and the studied PCR additives are useful in improvement of amplification in combination of 5 % DMSO and 1 M betaine.