Biomedical subjects

Jian-Rong Guo

Publications and source records attributed to Jian-Rong Guo.

4 recordsLinked to original sources

PubMed2006

Differences between the fingerprints generated from total RNA and poly-A RNA using a modified procedure of cDNA-AFLP and silver staining.

A modified procedure of cDNA-amplified fragment length polymorphism (cDNA-AFLP) combined with silver staining is described which generates clear band patterns from both fungal total RNA and poly-A RNA. The silver staining procedure takes only 25 min. Some 42-55 transcript-derived fragments (TDFs) were yielded from the total RNA of eight fungal pathogens. In comparison with the fingerprints generated from Mycosphaerella graminicola total RNA, those from poly-A RNA showed eight TDFs with an increased intensity and also seven additional TDFs. It suggests that poly-A RNA is preferable as starting material for ideal cDNA-AFLP analysis.

Comet Assay↗

PubMed2006

Presymptomatic and quantitative detection of Mycosphaerella graminicola development in wheat using a real-time PCR assay.

Presymptomatic and accurate diagnosis of Mycosphaerella graminicola leaf blotch is desirable for the disease prediction and the timely application of fungicides. To develop a sensitive PCR assay, four specific primer pairs were designed. They were more specific than three known specific primer pairs. Three of them could detect as little as 0.5 pg M. graminicola DNA in a conventional PCR. A real-time PCR assay was applied for monitoring the disease progression in both inoculated and naturally infected wheat plants using the primer pair ST-rRNA F/R. In inoculated plants, M. graminicola DNA could be detected immediately after inoculation and a steady increase was detected before visible symptoms appeared at 8 days. The rapid growth period took place between 6 and 16 days postinoculation. In the field, the disease progression in the top three leaf layers was followed during the epidemic period. The results were significantly correlated to the disease indices (R=0.8986) and also to the number of pycnidia per leaf (R=0.9227). These suggest that the real-time PCR assay is a reliable approach for the presymptomatic and accurate detection of M. graminicola development in the field.

Ascomycota↗

PubMed2005

Rapid and efficient extraction of genomic DNA from different phytopathogenic fungi using DNAzol reagent.

A modified procedure using the commercial DNAzol reagent was successfully applied to extract genomic DNA from 25 fungal species. The DNA yield varied from 306 to 1,927 microg g(-1) dry mycelia and the A(260)/A(280) ratio from 1.59 to 1.93. Compared with the method of J.L. Cenis (Nucleic Acids Res. 1992, 20: 2380) this procedure generated a higher DNA yield from 17 species and a higher A(260)/A(280) ratio from 23 species. But for four species, Cenis (1992) method was more suitable. No inhibitor of polymerase chain reaction was evident for the DNA extracted by the modified procedure, whereas some inhibitors remained in DNA of eight species extracted by the previous method.

Base Sequence↗

PubMed2004

Comparative assessment of genotyping methods for study genetic diversity of Fusarium oxysporum isolates.

In this study, we evaluated three PCR-based methods for the molecular typing of nonpathogenic Fusarium oxysporum isolates: random amplified polymorphic DNA (RAPD), polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) and amplified fragment length polymorphism (AFLP). The analyses were performed using 64 isolates of F. oxysporum collected from cotton-producing areas in Egypt. A number of polymorphic RAPD, PCR-RFLP and AFLP bands were scored in all isolates and the genetic similarity among them was assessed. Clustering analysis separated the isolates into two main groups, with similarities ranging from 87 to 100% for RAPD, 80 to 100% for PCR-RFLP and 88 to 97% for AFLP, respectively. The obtained data suggested that all three types of markers are equally informative, but the three assays differed in the amount of detected polymorphic bands. AFLP fingerprinting was also found to be more differentiating than other techniques for the typing of F. oxysporum populations.

DNA, Ribosomal Spacer↗