Entangling the interaction between essential and nonessential nutrients: Implications for global food security

Global food security requires a major boost in food production to match population growth. This goal is not achievable by simply maintaining current agronomical and breeding practices. Since the Green Revolution, fertilizers have been a backbone of modern agriculture. A doubled food production in the past 35 years came from a 6.9-fold increase in nitrogen fertilization and a fourfold increase in phosphorus fertilization. However, there is a growing recognition of the limitations of the first Green Revolution, mainly because developed technologies did not focus on the constraints to production in more marginal environments, such as drought, salinity, or flooding. Also, these stress factors often increase the availability of other (nonessential to plants) elements that may either interfere with uptake of essential nutrients (thus reducing their biological availability) or be taken by plants alongside the latter, causing detrimental effects on plant growth and the nutritional quality of the food. The current management practices are of a little help to entangle this issue. Instead, a deep understanding of the molecular basis of nutrient uptake and transport under adverse environmental conditions is required. This chapter provides a timely update on these matters, summarizing the current knowledge of mechanisms of acquisition of essential macronutrients and micronutrients under adverse environmental conditions and discussing the confounding effects of nonessential elements such as sodium, cadmium, or arsenic on plant nutrition and quality.