Stevia

AbstractStevia (Stevia rebaudiana(Bertoni)) is a small bush native to Paraguay. Stevia has been traditionally used as a medicinal herb for hundreds of years in various parts of the world. Stevia leaves are a rich source of a natural sweetener “stevioside” which is up to 300 times sweeter than sucrose. Stevia products are primarily known to be used as artificial low‐calorie sweetener while other important characteristics include antimicrobial, antibacterial, antiviral, and antiyeast activity. However, studies have shown that the stevioside content of leaves can vary substantially (5–20%) between individual plants. Such inherent natural variability could be partially explained by self‐incompatible nature of the flowers. Moreover, it is difficult to increase the commercial scale production by conventional means of sexual seed production due to poor seed germination. In addition, limited vegetative propagation is also a major constraint in Stevia production. The worldwide demand for high potency sweeteners is expected to increase in the near future that implicates developing alternative methods for rapid production of plants with high and uniform yields of sweeteners. Various efforts includingin vitroclonal propagation, gene transfer using cutting edge DNA delivery systems, rapid production and high frequency regeneration of transgenic homogenous population plants have been discussed in detail. Maximizing Stevia production through unconventional methods will unleash its potential to become an important nutritional and therapeutic supplement for the growing natural food market in the future.