![Sample our Food Science & Technology journals, sign in here to start your access, latest two full volumes FREE to you for 14 days]({"type":"image" , "src" : "/sda/5936/TOC-Subject-Sample-2021-Food-Science-Technology.jpg"})
Abstract
Plant foods can serve as dietary sources of all essential minerals required by humans. Unfortunately, mineral concentrations are low in some plants, especially many staple food crops; thus, efforts are underway to increase the mineral content of these foods as a means to ensure adequate attainment of dietary minerals in all individuals. While these efforts have included classical breeding approaches in the past, it is clear that future progress can be made by utilizing the tools of biotechnology to effect directed changes in plant mineral status. Reviewed are the short- and long-distance mineral transport mechanisms responsible for the root acquisition and whole-plant partitioning of mineral ions in crop plants. This background is used to discuss different transgenic strategies with the potential to enhance mineral content in vegetative and/or reproductive tissues. Due to various constraints imposed by plant transport systems on whole-plant mineral movement, it is argued that modifications designed to increase the supply of minerals to edible organs should have the highest chance for success. Examples of previous efforts to manipulate plant mineral nutrition through the introduction of novel transgenes are presented to demonstrate the utility of these approaches.
Key teaching points:
• Plants are capable of absorbing a wide range of mineral ions with relevance to human nutrition and health.
• Mineral concentrations in many plant foods are low, relative to human requirements; this has elicited efforts to enhance plant mineral content by using the tools of plant biotechnology.
• To be effective, transgenic strategies for mineral improvement must be designed to complement or enhance the existing mechanisms and regulatory processes that govern plant mineral nutrition.
• Processes relevant to plant nutrient content include mineral availability in the soil environment, short-distance ion movement using membrane transporters and long-distance mineral movement utilizing the xylem or phloem pathways.
• Different strategies are necessary to enhance the mineral content of xylem-fed tissues such as leaves versus phloem-fed tissues such as seeds.
• For seed crops, transgene expression designed to increase mineral loading into the phloem pathway is envisioned as a primary strategy to effectively enhance seed mineral content.
Key teaching points:
• Plants are capable of absorbing a wide range of mineral ions with relevance to human nutrition and health.
• Mineral concentrations in many plant foods are low, relative to human requirements; this has elicited efforts to enhance plant mineral content by using the tools of plant biotechnology.
• To be effective, transgenic strategies for mineral improvement must be designed to complement or enhance the existing mechanisms and regulatory processes that govern plant mineral nutrition.
• Processes relevant to plant nutrient content include mineral availability in the soil environment, short-distance ion movement using membrane transporters and long-distance mineral movement utilizing the xylem or phloem pathways.
• Different strategies are necessary to enhance the mineral content of xylem-fed tissues such as leaves versus phloem-fed tissues such as seeds.
• For seed crops, transgene expression designed to increase mineral loading into the phloem pathway is envisioned as a primary strategy to effectively enhance seed mineral content.
The writing of this review was supported in part by the US Department of Agriculture, Agricultural Research Service under Cooperative Agreement Number 58-6250-6-001. The contents of this publication do not necessarily reflect the views or policies of the US Department of Agriculture, nor does mention of trade names, commercial products, or organizations imply endorsement by the US Government.
