RESEARCH COMMUNICATIONS CURRENT SCIENCE, VOL. 106, NO. 5, 10 MARCH 2014 729 *For correspondence. (e-mail: rasaviswanathan@yahoo.co.in) is also valid as most pathogenic bacteria control the expression of their virulence factors rather tightly. The data presented here reveal a novel aspect. The TlyA that is devoid of rRNA methylation activity (con- tributed to evolution of second-line antibiotic resistance) can still reach the cell wall of the bacterium and aid the survival strategies. This indirectly suggests that the cell- wall association is not dependent on the rRNA methyla- tion activity. Based on these observations, we have a valid speculation that TlyA could be a virulence factor for the bacterium. For example, infection of THP-1 macro- phages with of Mycobacterium avium subsp. paratuber- culosis has resulted in 5-fold upregulation of its tlyA gene (protein ID: MAP_1401), which has over 80% identity with the Mtb protein studied here. 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Financial assistance for the work was provided by the Department of Biotechnology, New Delhi, through an intramural research of National Centre for Cell Science, Pune. Received 16 August 2013; revised accepted 22 January 2014 Quantification of Sugarcane yellow leaf virus in in vitro plantlets and asymptomatic plants of sugarcane by RT-qPCR C. Chinnaraja 1 , R. Viswanathan 1, *, M. Sathyabhama 1 , B. Parameswari 2 , K. Bagyalakshmi 1 , P. Malathi 1 and D. Neelamathi 3 1 Plant Pathology Laboratory, and 2 Sugarcane Breeding Institute Regional Centre (ICAR), Karnal 132 001, India 3 Micropropagation Laboratory, Sugarcane Breeding Institute (ICAR), Coimbatore 641 007, India Yellow leaf caused by Sugarcane yellow leaf virus (SCYLV) is a serious viral disease affecting production and productivity in many ruling sugarcane varieties in India. Usually the characteristic disease symptoms appear during maturity phases of the crop; also many of the infected varieties do not exhibit disease symp- toms and disease expression is influenced by virus titre and other factors, including the prevailing cli- mate. The present study was taken up to quantify and