Search

Tomato crop is known to be infected by large number of viruses across the globe causing severe losses in its yield. Accurate information on the distribution and incidence of different viruses is essential to implement virus control strategies. This study provides information on prevalence and distribution of different viruses infecting tomato crop in North-western region of India. Leaf samples of 76 symptomatic tomato and 30 symptomatic and asymptomatic plants of Chenopodium sp.(weed) were collected from eight villages. DAS-ELISA and/or RT-PCR/PCR were used to detect occurrence of nineteen viruses and one viroid in tomatoes. Nine viruses viz. cucumber mosaic virus, groundnut bud necrosis virus, potato virus M, potato virus S, potato virus X, potato virus Y, tomato chlorosis virus, tomato leaf curl New Delhi virus and tomato mosaic virus were detected in 58 of 76 tomato samples. Detection of viruses was confirmed by cloning of specific amplicons followed by sequencing and submission of sequences to the GenBank database. None of the targeted pathogens were found in collected weed samples. Tomato leaf curl New Delhi virus (ToLCNDV) was the most prevalent virus (64.47%) followed by potato virus Y (PVY) (23.68%). Double, triple, quadruple and quintuple infections were also noticed. Phylogenetic analysis of nucleotide sequences was also carried out. Nine viruses infecting tomato crop from North-western region of India were detected. ToLCNDV was most prevalent with highest incidence. To the best of our knowledge, this is the first report of ToCV on tomato from India.

Nocardia farcinica causes human infections either by pulmonary inhalation or inoculation via wounds and causes nocardiosis, brain abscesses and secondary infection in immune-compromised patients. N. farcinica infection is mostly reported in Asia, Europe and North America with a mortality rate of 10-31%. Antibiotic treatment available for N. farcinica infection have the problem of side-effects and drug resistance development by bacteria against antibiotics such as ampicillin, third- generation cephalosporins, etc. Therefore, this paper explored riboswitch as an alternative drug-target to address these issues and its optimal inhibitors are designed. Riboswitches are regulatory elements found in the 5′UTRs of many mRNAs. The designed lead molecule will prove helpful in the development of newer drug molecules for the infection treatment caused by N. farcinica. The proposed inhibitors are supposed to be free from the problem of side-effects and drug-resistance associated with antibiotics, as there are remote chances of mutations in riboswitches.