Cultivation of Stevia rebaudiana Bertoni and Associated Challenges

Abstract

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 artificial intensive sweeteners. The worldwide demand for purified steviol glycosides 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 cultivation 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 significant improvement of its cultivation should be achieved and a modern agronomical blueprint defined. It is, in fact, imperative to develop economically viable and environmentally sustainable crop production systems through the integration of site-specific agronomic techniques and efficient 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 production chain are the strongest points, in order to obtain a certification 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 scientific information regarding the most important agronomic factors in order to foster stevia cultivation and attain maximum yield and quality.

Optimized Nitrogen Topdressing Strategies Enhance Steviol Glycoside Productivity in Stevia (Stevia rebaudiana Bertoni) Plants

“…A total of six treatments were established in a randomized block design in this experiment, with four replicates per treatment. According to Angelini et al (2018) and our previous study on stevia, the total N (in the form of urea) fertilization rate over all stages was 300 kg ha −1 , to meet the N demand for stevia growth and maximum SG accumulation. Then, different N topdressing strategies were adopted (Fig.…”

Phenological growth stages of stevia (Stevia rebaudiana Bertoni) according to the Biologische Bundesanstalt Bundessortenamt and Chemical Industry (BBCH) scale

“…On stevia, two types of seeds can be distinguished: sterile seeds, which present a light or white coloration and do not reach full size, and fertile seeds, which present a dark coloration and a normal size (Figure 1a). Most of the time, stevia presents a low germination rate because of the ratio between sterile seeds and fertile seeds (Angelini et al, 2018), which is not suitable for direct sowing (Khalil et al, 2014; Yadav et al, 2011). It can also be an obstacle high plantlet production.…”

“…In southwest France bud development occurs in March or April depending on the genetic resources. It is a critical stage because an early bud swell will increase the risk of frost damage (Angelini et al, 2018).…”

Growth and Development of Stevia Cuttings During Propagation with Hormones in Different Months of the Year

“…Because of this and other therapeutic applications [2], with beneficial effects on type II diabetes and obesity [8] and antibacterial and anticancer effects [2], stevia is considered a medicinal plant [10]. The worldwide concern for chronic degenerative diseases and the demand for healthy foods in western societies have stimulated a strong interest in stevia as an alternative to sucrose and artificial sweeteners [11]. The natural antioxidants in stevia can replace synthetic antioxidants such as BHA (butylated hydroxy anisole) and BHT (butylated hydroxytoluene), which have been restricted in their use because they are potential carcinogens [2].…”