New Technologies for Assay and Management of Plant Viruses and Virus-Like Agents: 1- Assay

Effective assay of the disease agents is a prerequisite for successful management of plant diseases caused by viruses and virus-like pathogens. The assays may be biological (i.e., based on infectivity), morphological (shape and size, e.g., based on electron microscopy), or based on the properties of the pathogen proteins and nucleic acids. Methods based on the properties of the pathogen proteins include various serological techniques such as enzyme-linked immunosorbent assay (ELISA), microarray, electrophoresis and certain types of biosensing. Methods based on the properties of the pathogen genome include hybridization tests, microarray chips, polymerase chain reaction (PCR) and next generation sequencing (NGS) technologies. Combinations of these methods such as immuno-electron microscopy, immuno-electrophoresis and immunocapture PCR may also be used. In this article feasibility, sensitivity, specificity and uses of these techniques are pointed out. At the present the most commonly used methods for targeted detection of plant pathogens are various modifications of ELISA, LAMP and PCR. Types of NGS technologies are the methods of choice for non-target assay of plants for these pathogens. Bioinformatics tools have played an unparalleled role in the advancement of new technologies. All technologies are eco-compatible and can be used or adapted in the country.