Micro-element contents of roselle (Hibiscus sabdariffa L.) at different growth stages

Abstract

In the western Sahel, leaves of Roselle (Hibiscus sabdariffa) have considerable economic importance because of their nutritional and medical uses. These plant organs are used to supplement nutrients provided by cereals such as millet and sorghum. However, there is a lack of information on the nutrient composition of these plant organs of Roselle at different growth stages. Therefore, the experiment was carried out under rainfall conditions during the 2006 rainy season (from July to September) at the experimental station of the Agrhymet Regional Centre in Niamey (Niger). The content of the micronutrients Fe, Mn, Cu and Zn in leaves of three ecotypes of Roselle (A3, A7 and A9) at three growth stages, vegetative (stage I), flowering (stage II), and mature (stage III) was determined. The experimental design was a randomized complete block with four replicates and one variable (ecotype). Results indicated that at stage I, ecotype A3 had higher Fe content in leaves. In addition, A3 had also the highest Zn content in leaves at stage I. For all three ecotypes, Fe and Zn content in the leaves decreased significantly (p