Plant Virology Laboratory Department of Mycology and Plant Pathology, Dr. Y S Parmar University of Horticulture and Forestry, Nauni, Solan – 173230
National Symposium on Strategic Issues in Plant Pathological Research held at Department of Plant Pathology, CSK HP Krishi Vishvavidayalaya, Palampur on November 24–25, 2011
Apple stem grooving capillovirus (ASGV) is one of the most important and widespread virus infecting apple in the world. Of late, the virus has been found to be invariably associated with most of the apple crop of Shimla district of Himachal Pradesh. Sero-diagnostic investigations have revealed that the virus concentration in the infected trees fluctuates round the year thereby, making it difficult to ascertain the virus- free status of such plants. Since optical density (O.D.) value in the sero-positive sample is also an indicator of virus concentration, microplate reader MS 5605A was used to work out the virus concentration based on O.D. values at 405 nm. Therefore, suitability of double antibody sandwich (DAS) form of enzyme linked immuno-sorbent assay (ELISA) on O.D. value basis in the detection of ASGV in different plant parts throughout the year has been checked in the present studies. ASGV was found in detectable limits in leaf samples drawn from infected trees during March to June and in August months; in bark tissues from February to September and from petals and fruits in April and June months, respectively. However, maximum concentration on O.D value basis of the virus was found in petals followed by leaves and bark samples taken during the month of April. Therefore, these parts could be used for serological detection of the virus during different growth periods with petals and leaves samples drawn during April as the most appropriate plant parts for reliable detection of ASGV.
