Recent advances in plant virus detection

Abstract

From the past 15-20 years, enzyme-linked immunosorbent assays (ELISA), involving polyclonal antibodies, are still the widely used method for practical plant virus detection. Many commercial plant virus detection kits are designed based on that principle. When monoclonal antibodies are introduced, they become extremely useful for detecting specific virus strains or viruses that are present in low concentrations in infected plant tissues. However, due to the high cost of producing them, they are not as widely used as the polyclonal antibodies. After the polymerase chain reaction (PCR) was invented, the technique rapidly extended its application to plant virus detection. At first many reports appeared in the literature reporting the unprecedented sensitivity in detecting individual plant viruses. Subsequently, immuno-capture PCR method and group-specific PCR primers for virus detection are available. More recently, the use of one pair of PCR primers to detect two different viruses simultaneously in the same plant tissue has been reported. Competitive and quantitative real-time PCR are being developed to detect minute differences in the amount of viruses from a mixed infection. Other recent advances in molecular techniques and instrumentation, including the molecular beacons, capillary zone electrophoresis, liquid chromatography (LC)-and matrix-assisted desorption-ionization (MALDI)-mass spectrometry, quartz crystal microbalance-based nucleic acid biosensor and nucleic acid sequence based amplification (NASBA), have lead to even wider choices for plant virus detection. While some of these new methods are still in the research phase, the potential power of these methods for plant virus detection is enormous.