Détermination de la teneur en calcium, magnésium, fer et zinc de cinq cultivars de Gombo, Abelmoschus esculentus (L.) Moench (Malvaceae), cultivés à Bujumbura

Abstract

The aim of this work is to determine the Ca, Mg, Fe and Zn contents of five okra (Abelmoschus esculentus) cultivars grown in  Burundi. Comparative analysis between okra cultivars and between okra organs (leaf and fruit) in order to suggest better  cultivars for food were also carried out. Five Okra cultivars (G1, G2, G3, G4, and G5) were cultivated on an experimental  field of the Centre de Recherche en Sciences Naturelles et de l’Environnement (CRSNE) of the University of Burundi. Young fruits and terminal young leaves of each cultivar were systematically sampled. The minerals were determined by atomic absorption spectrophotometry (AAS). The Principal Component Analysis (PCA) revealed negative correlation of variation in  Ca, Mg, Fe, and Zn content of the leaves to those of the fruits. Furthermore, the five cultivars we regrouped according to their  similarity of variation in mineral content. In this case, G2 and G3 cultivars showed very close variations in mineral content.  The Analysis of Variance (ANOVA) and Tukey test showed that, for all cultivars, the leaves have higher mineral content (P value <5%) than fruits. The maximum contents registered for 100g of DM are: 7342.40±90.86mg Ca (G3), 269.20±3.92mg  Mg (G5), 41.47±4.19mg Fe (G3), 8.42 ±0.48mg Zn (G4). The fruits showed relatively low mineral contents without significant differences (P-value ˃5%) except for Mg. It has also been noted that the mineral contents of Burundi okra cultivars have high levels of minerals, sometimes exceeding 100% of daily dietary recommendations.