Molecular characterization of the phytoplasmas associated with toon trees and periwinkle in India

In November 2008 in Himachal Pradesh and Chandigarh regions in India, toon trees and periwinkles were observed to have formed short internodes, small leaves and witches’-broom symptoms, typical of phytoplasma infection. The symptomatic toon and periwinkle samples were tested with universal PCR tests, and the 16S rRNA, rplB-rpsC, secA and secY genes were sequenced. The causal agents belonged to subgroup 16SrI-B of ‘Candidatus Phytoplasma asteris’, based on 16S rDNA, ribosomal protein gene, secA and secY phylogenetic analysis.     

Molecular characterization and variability analysis of <Emphasis Type="Italic">Apple scar skin viroid</Emphasis> in India

Apple scar skin viroid (ASSVd) infection is a major limitation to apple fruit quality and causes huge economic losses. In surveys of apple orchards in the northern Indian state of Himachal Pradesh, fruits with dappling symptoms were noticed. ASSVd was detected from these fruits and molecularly characterized. Ten clones from three isolates were sequenced, of which seven were new sequence variants of ASSVd. The clones had significant sequence variability (94–100%) with each other. Variability was more common in the pathogenic domain of the viroid genome. Four of the clones were 330 nucleotides (nt) long, and the other six had an additional nucleotide. Phylogenetic analysis showed close affinity of the present isolates with some Chinese and Korean isolates. The study reports seven new variants of ASSVd and also provides the first molecular evidence of viroid infection (ASSVd) in apple in India.     

Occurrence of Peanut stripe virus on patchouli and raising of virus-free patchouli plants by meristem tip culture

Journal of Plant Diseases and Protection - Patchouli (Pogostemon cablin) was found infected with a viral disease showing mosaic symptoms on the leaves in the Chand-pur farm at Institute of...     

Variability in the coat protein of Lily symptomless virus isolates infecting various lily species

The coat protein sequences were characterized of Lily symptomless virus (LSV) isolates infecting Lilium longiflorum , Lilium tigrinum , Hymenocalis littoralis (spider lily) and Asiatic and Oriental hybrid lilies in India. The Indian isolates showed 78–96% homology with each other. With LSV isolates from elsewhere in the world, the Indian isolates showed 83–98% homology. The LSV-L ( L. longiflorum ) and LSV-A (Asiatic hybrid) isolates had unique stretches in the middle portion of the protein not found in other LSV isolates, even the Indian ones. The LSV gene sequence from the spider lily isolate (LSV-S) was reported for the first time outside the Liliaceae. LSV-S was 84–96% similar to the other Indian isolates at the protein level. The isolate infecting tiger lily (LSV-T) was found to be different from the characterized isolates from elsewhere in the world (78–84% homology at the protein level). At the same time, LSV-T showed much variability in the C-terminal of the protein. A stretch of 41 amino acids in the C-terminal was unique to this isolate. LSV-T is proposed as a distinct isolate of LSV infecting L. tigrinum indigenous to India.