First Report of Grapevine leafroll-associated virus 1 Infecting Grapevines in India

Viticulture, one of the most remunerative farming enterprises of India, is seriously affected by leafroll disease, which accounts for 62% of the losses in grape production worldwide due to viral diseases (4). Grapevine leafroll-associated virus 3 and 1 (GLRaV-3 and GLRaV-1) of the family Closteroviridae are the two most common viruses associated with the leafroll disease of grapevine (1). GLRaV-3 was previously confirmed in India through RT-PCR, cloning, and sequencing (2). A survey was conducted during 2010 and 2011 in the Nashik and Pune regions of western India and reddening of interveinal areas and downward rolling, typical symptoms of leafroll disease in dark fruited cultivars, were observed, first in 2010 and subsequently in 2011. Fourteen leafroll symptomatic samples from seven cultivars of seven vineyards were collected during 2011. Samples were subjected to double antibody sandwich (DAS)-ELISA using commercially available antibodies against GLRaV-3 and GLRaV-1 (Bioreba, Reinach, Switzerland) (2). An asymptomatic sample from another cultivar of a different vineyard and samples from two plantlets of two different cultivars produced in tissue culture were used as negative controls. GLRaV-1 was detected in two cultivars, Shiraj (Nashik region) and Pinot Noir (Pune region) using DAS-ELISA. GLRaV-1 was detected either alone in cultivar Pinot Noir or as mixed infection with GLRaV-3 in cultivar Shiraj. To further confirm the presence of GLRaV-1 in these two cultivars, crude extract from petioles of these two cultivars were subjected to one step reverse transcription (RT)-PCR using GLRaV-1 specific primers pORF9F and pORF9R (GGCTCGAGATGGCGTCACTTATACCTA and CCTCTAGACACCAAATTGCTAGCGA, respectively) (3). The ˜650 bp amplicons were cloned in pGEM-T easy vector and three independent clones of each amplicon were sequenced in both directions. The cloned amplified product was 646 bp, including 630 bp of p24 protein (ORF9) of GLRaV-1. Comparative sequence analysis, using the BioEdit 7.0.3 program ( http://www.mbio.ncsu.edu/BioEdit/BioEdit.html ), of ORF9 of the virus under study from the cultivars Pinot Noir and Shiraj shared maximum sequence identity of 95.8 and 96.1%, respectively, at the nucleotide level with the Clatervine isolate from the United States (GenBank Accession No. HQ833477). The corresponding values of maximum identities at the amino acid level were 96.6 and 96.1%, respectively, with the same Clatervine isolate. The maximum identity between these two isolates of GLRaV-1 was 96.1% at nucleotide level and 95.7% at amino acid level. To the best of our knowledge, this study represents the first report of GLRaV-1 from India. Grape production in India could be impacted by this virus; thus, identification of the virus is important. References: (1) B. Akbas et al. Hort. Sc. (Prague). 36: 97, 2009. (2) S. Kumar et al. Virus Genes. 45:195, 2012. (3) A. Little and M. A. Rezaian. Arch. Virol. 151:753, 2006. (4) A. Little et al. Virus Res. 80:109, 2001.

Evaluation of Fermentation Efficiency of Yeast Strains and their Effect on Quality of Young Wines

The yeast has important role in fermentation of wine grapes and wine quality. The fermentation of wine grapes affect by efficiency of particular yeast strain, sugar content, pH, available temperature, etc. To evaluate the efficiency of yeast strains (Premier Cuvee, RS-1, RS-2, RS-3 and natural), present study was conducted on two wine grape varieties viz.; Sauvignon Blanc (White) and Cabernet Sauvignon (Red). Efficiency of yeast strains was evaluated in terms of conversion rate of sugar into alcohol. As per recorded data, strain RS-3 (Pichia kudriavzevii) was found more efficient than other strains in fermentation of Cabernet Sauvignon with efficiency of 84.4 per cent but in case of Sauvignon Blanc, the commercial culture Premier Cuevee was found superior over RS-3. The quality parameters of young wines of both the varieties were also affected by the used strains. Considering the efficiency and impact on various parameters of wines, local strain, i.e., RS-3 was found at par with commercial culture (Premier Cuvee). The RS-3 strain has potential to produce quality wines. However, studies on effects of RS-3 strain on some specific quality parameters of wines like varietal aroma compounds, flavours etc. are needed.

Isolation and serological characterization of a Plasmodium vivax recombinant antigen

A genomic library for Plasmodium vivax was constructed in lambda gt11 and immunologically screened with pooled serum samples from vivax patients. Six seroreactive clones were isolated, and one clone, denoted PV9, was studied further. This clone has an unusual base composition (65% G + C), does not share any homology with P. falciparum, and codes for an entirely new antigenic determinant. Antibodies (immunoglobulin G type) against the PV9-encoded polypeptide were produced in all vivax patients older than 15 years. This seroreactivity was lower among patients younger than 15 years (53%). The antigenic epitope(s) of the PV9-encoded polypeptide was recognized at a similar rate by serum samples from P. vivax patients who were living 350 to 973 km apart. Fifty percent of uninfected Indian adults were also seropositive, whereas all European and American (United States) sera tested were negative, suggesting that anti-PV9 antibodies persist after infection. The seroreactivity pattern of this antigen is similar to that of the immunity developed in malaria after repeated infections.