Cultivation of Stevia rebaudiana Bertoni and Associated Challenges.

The rising concern about the spread of obesity and diabetes and a growing awareness about healthy foods in western societies have stimulated in the last years a strong interest toward stevia sweeteners as alternative of sucrose and artifi cial intensive sweeteners. The worldwide demand for purifi ed steviol glyco- sides from stevia is steadily increasing, and it is expected that in the future the agricultural production capacity will be lower than the market demand. This provides a strong incentive to explore the possibilities to cultivate stevia and to produce leaves and extracts, beyond the traditional production zones. The culti- vation of stevia might represent a formidable opportunity for the growers, in order to diversify the cropping systems and to meet the increasing market demand for high-quality and traceable raw material. In addition, several legislative initiatives, such as the steviol glycosides approval as food additive in several countries, represent favorable factors for the development of a stevia-based agro-industry. To foster the introduction of this novel species, a signifi cant improvement of its cultivation should be achieved and a modern agronomical blueprint defi ned. It is in fact imperative to develop economically viable and environmentally sustain- able crop production systems through the integration of site-specifi c agronomic techniques and effi cient mechanization technologies for the production and processing of a higher quality product. Several agronomic aspects require still to be optimized (e.g., choice of the cultivar, propagation and transplanting, sustainable weed management, nutrition, irrigation, harvesting), in order to improve, not only the leaf yield but also its quality in terms of steviol glycosides and bioactive compounds. Traceability and crop quality control along the pro- duction chain are the strongest points, in order to obtain a certifi cation that will provide to the farmers preferential market access and to sell the raw material at a differential price. The present chapter, therefore, aims to provide updated scientifi c information regarding the most important agronomic factors in order to foster stevia cultivation and attain maximum yield and quality