Micronutrients: soil to seed

Official URL: https://dx.doi.org/10.1007/978-981-16-3280-8_20

Plants are the main dietary resource of micronutrients essential for humans. But staple food crops on which people of poor and developing countries feed, do not contain sufficient micronutrient metals and thus results in poor growth, mental disorders and increased mortality of human consumers. Knowledge on mechanism of micronutrient uptake by plant roots, their accumulation in subcellular compartments, long-distance transport in vascular tissues, allocation to economic sinks of crop plant, etc. is, thus, of utmost importance in the biofortification programmes, implemented for nutrient enrichment of plant foods. The present chapter gives an insight on various physiological aspects regulating micronutrient absorption in crop plants. Despite the role of edaphic factors controlling micronutrient availability in soil solution, biological activity of root organs is also determinant of micronutrient metal uptake from rhizosphere. The charged nature of essential micronutrients, which are mostly divalent cations, needs sophisticated transporters for their delivery to respective sinks. Further to achieve metal homeostasis and to reduce their toxicity, root to shoot and shoot to root signalling is in concordance with metal chelators and transporters, which have been discussed in detail in present chapter. Finally, future research avenues have been discussed which can be targeted to enhance the efficacy of crop biofortification.