Identification, detection and frequency of lily viruses in Northern India

Abstract

In a survey of lily growing fields in various parts of Himachal Pradesh, India, three viruses, Cucumber mosaic (CMV), Lily symptomless (LSV) and Lily mottle virus (LMoV) lily strain, were found quite prevalent in Asiatic (12 cultivars) and Oriental hybrids (4 cultivars) of lily, Lilium longiflorum and L. tigrinum. Apart from these viruses, Strawberry latent ringspot virus (SLRSV) was also found to infect Oriental hybrid lily. The disease incidence on the basis of symptoms observed ranged between minimum (40.7%) in cv. Alaska and maximum (83.7%) in cv. America, both Asiatic hybrid lily types. These viruses were indexed by testing outer and inner scales of bulbs and the leaves at early and flowering stages using ELISA and reverse transcription polymerase chain reaction (RT-PCR). Mechanical and insect transmission, purification, electron microscopy and sequencing of the PCR fragments were carried out for these viruses. Cloning and sequence analysis confirmed the viruses as CMV-subgroup II, LSV and LMoV. There were 96–98% nucleotide and 93–97% amino acid homology with CMV subgroup II sequences, 97–99% nucleotide and 91–92% amino acid homology with LSV sequences and 92–99% nucleotide and 85–98% amino acid homology with LMoV sequences.