Publicação
Biomass production and nutrient concentration on potted Stevia in response to N, P, K or B fertilization
| Resumo: | Stevia rebaudiana (Bertoni) is a perennial plant belonging to Asteraceae family, native from Amambay region, between Brazil and Paraguay. It has been used for centuries by Guarani Indians as a sweetener and to treat diabetes. Stevia composition includes glycosides from steviol, the steviosides, natural sweeteners that reduce blood glucose, noncaloric, with a sweetening power much higher than sucrose. Studies also showed a high content of proteins, K, P, Mg, Ca and trace of copper, iron, manganese and zinc. Japan was one of the first countries to commercialize stevia based products and to establish it as a crop, and since then interest has expanded overall. European Union only authorized stevia as a food additive since 2011. Natural and healthy alternatives to sugar are being more preferred by consumers, explaining the great increased of stevia based products, and the perspectives are for stevia consumption to increase even more in the coming years. Also there is a growing scientific interest on stevia. However, agronomic knowledge is still scarce. This investigation aimed to assess the effect of increasing rates of N, P, K or B application on stevia biomass production and nutrient concentration in plant tissues. The effect of fertilizer treatments on stevia was also assessed through the use of the portable chlorophyll meter SPAD-502 plus which estimate leaf chlorophyll content. A pot experiment was installed as a randomized design with four replications. Five rates of each nutrient were applied, namely N (0, 0.75, 1.5, 2.25, 2 g/pot), K (0, 0.25, 0.5, 1, 1.25 g/pot), P (0, 1.25, 2.5, 3.75, 5 g/pot), or B (0, 0.025, 0.05, 0.075, 0.1 g/pot). The data is important to adjust fertilizer rates to crop demands, enabling to maximize production and improve the nutritional value of stevia products. Results showed a significant increase of dry biomass in response to N fertilization, attaining the higher values with a rate of 1.5 g N/ pot. There were not found significant differences in dry matter yield with P, K or B fertilizer rates. SPAD readings showed a slight variation with N fertilization and maximum values were recorded in the 1.5 g N/pot treatment. |
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| Autores principais: | Afonso, Sandra |
| Outros Autores: | Arrobas, Margarida; Rodrigues, M.A. |
| Assunto: | Stevia rebaudiana Fertilization Biomass production Tissue elemental composition |
| Ano: | 2017 |
| País: | Portugal |
| Tipo de documento: | documento de conferência |
| Tipo de acesso: | acesso aberto |
| Instituição associada: | Instituto Politécnico de Bragança |
| Idioma: | inglês |
| Origem: | Biblioteca Digital do IPB |
| Resumo: | Stevia rebaudiana (Bertoni) is a perennial plant belonging to Asteraceae family, native from Amambay region, between Brazil and Paraguay. It has been used for centuries by Guarani Indians as a sweetener and to treat diabetes. Stevia composition includes glycosides from steviol, the steviosides, natural sweeteners that reduce blood glucose, noncaloric, with a sweetening power much higher than sucrose. Studies also showed a high content of proteins, K, P, Mg, Ca and trace of copper, iron, manganese and zinc. Japan was one of the first countries to commercialize stevia based products and to establish it as a crop, and since then interest has expanded overall. European Union only authorized stevia as a food additive since 2011. Natural and healthy alternatives to sugar are being more preferred by consumers, explaining the great increased of stevia based products, and the perspectives are for stevia consumption to increase even more in the coming years. Also there is a growing scientific interest on stevia. However, agronomic knowledge is still scarce. This investigation aimed to assess the effect of increasing rates of N, P, K or B application on stevia biomass production and nutrient concentration in plant tissues. The effect of fertilizer treatments on stevia was also assessed through the use of the portable chlorophyll meter SPAD-502 plus which estimate leaf chlorophyll content. A pot experiment was installed as a randomized design with four replications. Five rates of each nutrient were applied, namely N (0, 0.75, 1.5, 2.25, 2 g/pot), K (0, 0.25, 0.5, 1, 1.25 g/pot), P (0, 1.25, 2.5, 3.75, 5 g/pot), or B (0, 0.025, 0.05, 0.075, 0.1 g/pot). The data is important to adjust fertilizer rates to crop demands, enabling to maximize production and improve the nutritional value of stevia products. Results showed a significant increase of dry biomass in response to N fertilization, attaining the higher values with a rate of 1.5 g N/ pot. There were not found significant differences in dry matter yield with P, K or B fertilizer rates. SPAD readings showed a slight variation with N fertilization and maximum values were recorded in the 1.5 g N/pot treatment. |
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