Geographical Distribution, Botanical Description and Self-Incompatibility Mechanism of Genus Stevia

Stevia rebaudiana Bertoni, popularly known as 'candy leaf', is a sweet native herb of Paraguay. It became economically important for its significant contribution to the sugar and beverage industry throughout the world. This plant has been known to contain a calorie-free natural sugar in its leaves, which is an alternative to other artificially produced sugar substitutes. Stevia is conventionally propagated through seed and cutting, owing to its self-incompatibility, insufficient pollinator activity, and poor seed set, which results in the origination of heterozygous plants with varying concentration of glucosides in leaves, with low multiplication rate. This article compiles the literatures and depicts an overview on the geographical distribution, morphological, reproductive and cytological features, along with incompatibility mechanism of Stevia that would assist researchers to explore further and genetically refine this potential herb with immense medicinal importance.