Potato viruses and their diagnostic techniques: An overview

Potato (Solanum tuberosum L.) is a vulnerable host of several plants viruses and viroid resulted severe yield losses. The viruses and viroid cannot be controlled therapeutically as there is no direct chemical available globally. Hence, in the first instant their control relies on inhibit the establishment, evolution and dispersal of the causal viruses, and to prevent them, the effective detection technique is much important. The development of reliable and specific detection methods is a compulsion and strong virus indexing is the only way to produce healthy seed potato. Detection of potato viruses is becoming more crucial because of globalization of trade by free trade agreement and therefore, a concern for national quarantine services to ensure the safe movement of potato germplasm across the border. The identification and detection of viruses is not an easy task as in case of fungi and bacteria, they can be seen only in a transmission electron microscope. Potato viruses are host specific and for accurate identification, appropriate detection method from sampling to final step must be deployed. In this review, several methods for virus and viroid detection are discussed with more emphasis on recently developed molecular diagnostic techniques. Molecular diagnostic techniques may be the choice for disease free seed potato production but for epidemiological and aetiological studies, biological indexing, serological and electron microscopy techniques are essential. This exercise will be helpful in sustainable agriculture and reliable health monitoring of potato as well as added knowledge to the researchers for adequate utilization of these techniques.