Critical evaluation of strategies for mineral fortification of staple food crops

Abstract

Staple food crops, in particular cereal grains, are poor sources of key mineral nutrients. As a result, the world's poorest people, generally those subsisting on a monotonous cereal diet, are also those most vulnerable to mineral deficiency diseases. Various strategies have been proposed to deal with micronutrient deficiencies including the provision of mineral supplements, the fortification of processed food, the biofortification of crop plants at source with mineral-rich fertilizers and the implementation of breeding programs and genetic engineering approaches to generate mineral-rich varieties of staple crops. This review provides a critical comparison of the strategies that have been developed to address deficiencies in five key mineral nutrients-iodine, iron, zinc, calcium and selenium-and discusses the most recent advances in genetic engineering to increase mineral levels and bioavailability in our most important staple food crops.

Nutritionally Enhanced Staple Food Crops

“…The adoption of nutritionally enhanced food crops will improve the health and well-being of the world's poorest people, but this advancement will only be possible if political differences over the development and use of transgenic crops are set aside and their deployment and cultivation is regulated according to robust, science-based criteria (Naqvi et al 2009a,b;Ramessar et al 2009;Gomez-Galera et al 2010). …”

Strategies to increase zinc deficiency tolerance and homeostasis in plants

“…An promising and cost-effective alternative strategy is improving plant zinc use efficiency and grain zinc content by plant breeding or genetic engineering. Such biofortification approach is one of the aims of the international Harvest Plus Consortium, which supports the development of new high-zinc content genotypes for increased zinc content in food and crops Gómez-Galera et al, 2010). Although biotechnological techniques advances and significant progress in understanding structures involved in metal homeostasis have driven research in this field, still little is known about the regulators of zinc homeostasis network in plants.…”

“…Since there appears to be genetic variation for this ability, plant breeding and genetic engineering approaches can be used to develop new high-zinc content crop genotypes. They are expected to increase the crop production in areas with low-zinc bioavailability and alleviate human malnutrition problems due to zinc deficiency Gómez-Galera et al, 2010).…”

Enhanced iron and zinc accumulation in genetically engineered wheat plants using sickle alfalfa (Medicago falcataL.) ferritin gene

“…Improving crop varieties using modern genetic engineering or conventional breeding to increase the iron content has the advantage of sustainability, i.e., the biofortified crops will not require further investment, unlike the addition of iron-containing chemicals to food or the use of iron supplements in pill form (Gomez et al 2010). Hence, it is best to develop iron-biofortified foods through the application of technology.…”