Sugarcane yellow leaf virus in Mauritius: (I) Recent progress in the application of real-time PCR for its diagnosis; (II) Genotypes observed in variety collections
| MSI08P4320 | |
| Joomun, N Dookun-Saumtally, A | |
| Sugarcane yellow leaf virus in Mauritius: (I) Recent progress in the application of real-time PCR for its diagnosis; (II) Genotypes observed in variety collections | |
| Programme and Abstracts: Advances and Challenges in Sugarcane Biotechnology and Plant Pathology - ISSCT IX Plant Pathology and VI Molecular Biology Workshop, Cali, Colombia, 23 - 27 June 2008 | |
| book chapter | |
| 2008 | |
| p. 21 | |
| Abstract only | |
| En | |
| En | |
| Sugarcane yellow leaf virus (SCYLV), the causal agent of yellow leaf disease in sugarcane, is widely encountered in most commercial varieties in Mauritius. At the Mauritius Sugar INdustry Research Institute (MSIRI), virus detection methods in routine use include the Tissue Blot Immunoassay (TBIA) and Reverse Transcriptase-PCR (RT-PCR). Although TBIA allows a large number of samples to be processed at a low cost, RT-PCR is the method of choice due to its high sensitivity and it is used to test varieties in quarantine as well as to ensure freedom of the virus in tissue culture plantlets. Recently, the real-time fluorescent Taqman RT-PCR assay, as described by Korimbocus et al (2002), has been introduced. This method allows the simultaneaous detection of the virus and a sugar cane internal control and was found to be 100-fold more sensitive than conventional RT-PCR. Total nucleic acids extracted from sugar primers CPR (for virus) and 570R (for plant internal control). The fluorescent Taqman probes (SCYLV and O-met) were then added in the PCR mix together with forward primers CPF and 501F. Thermal cycling and fluorescent detection were performed in a Chromo 4 (TM) Four-Color Real-Time System from Bio-Rad. The O-met internal positive control increases the reliability of the test by eliminating false negatives. Genetic diversity studies were performed using a two-step RT-PCR with primers developed by Abu Ahmad et al (2006) using total nucleic acids extracted using the CTAB method as template. Thirteen sugar cane varieties with yellowing symptoms from a foreign variety collection plot were screened with genotype-specific primers CUB-F/CUB-R, REU-F/B-REV, and PER-F/PEr-R. All 13 varieties were infected by SCYLV. The REU genotype, which is widespread in Reunion Island, was observed in ten of them. Two of these ten varieties also showed mixed infection with either the CUB or BRA-PER genotype. The BRA-PER genotype was also observed in three varieties. Only REU has so far been observed in Mauritian commercial varieties. The presence of the CUB and BRA-PER genotypes in the germplasm collection suggest that these genotypes could have been introduced from other countries a long time back while varieties with the REU genotype could have been infected in Mauritius. As variation in infection capacity and virulence amongst the different genotypes exist, genotype identification is crucial and studies along this line have been initiated. | |
| sugarcane sugarcane yellow leaf virus yellow leaf disease diseases PCR disease diagnosis real-time PCR RT-PCR diagnostic techniques virus detection variation genetic diversity genotypes | |
| Mauritius | |
| Sugarcane: Diseases and disease management | |
| Virus diseases: Sugarcane yellow leaf virus | |
| 2008-12-18 | |
| En | |
| BIOTECH | |
| CAT | |
| BIOTECH |