Missing association between nutrient concentrations in leaves and edible parts of food crops - A neglected food security issue

Abstract

Crop nutrient deficiencies are determined based on leaf nutrient composition, and rarely on food composition. Consequently, it remains unclear whether leaf nutrients are useable to form conclusions on quality of produced foods. This study aimed to investigate the relationships between plant macro- (Mg, P, S, K, Ca) and micronutrient (Fe, Zn, Mn, Cu) concentrations of leaves and edible parts of three East African staple crops: Zea mays, Manihot esculenta, and Musa acuminata. Low phloem mobile nutrients Ca, Mn, Fe, Zn, and Cu showed the largest differences in correlations between leaves and edible parts. Perennial crops showed lower correlations between nutrient concentrations of leaves and edible parts than annuals. Leaves may provide information on plant health, however do not provide enough information to gauge both yields and food quality, particularly regarding micronutrients. Therefore, agricultural and nutritional scientists should harmonize methods to develop sustainable management options for increased food and nutrition security.

Keywords: Analytical methods; Food composition; Nutritional quality; Remobilization; Trace elements; Yields.