Impact of Sildenafil Citrate on Tissue Culture of Tobacco (Nicotiana tabaccum)

Plant growth is controlled by several biochemicals that are collectively known as plant growth substances or hormones or regulators. One among them is nitrogen monoxide commonly known as Nitric oxide (NO-). The enzymatic activity responsible for NO- generation is NOS, which uses L-arginine as substrate, promoting its oxidation, with NADPH and oxygen consumption, and yielding L-citrulline and NO. The study of NO- has created considerable interest in the identification of promoters of Nitric Oxide Synthase (NOS). Several chemicals have been identified that release directly or induce the release of NO- within biological systems, one of them being Sildenafil citrate. Sildenafil citrate was added to basal MS medium for tissue culture studies. A good response could be observed in germination of tobacco when it was added to the medium. Within shorter time periods an increase in number of roots, root length and number of leaves could be observed.