Submitted to: Field Crops Research
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/30/1997
Publication Date: N/A
Interpretive Summary: The micronutrients iron, copper, zinc, and manganese are essential for the proper growth and development of plants. Because plants accumulate these nutrients in seeds and other edible organs, plant foods are important dietary sources of these nutrients for humans. Scientists have been investigating the ways in which plants absorb these nutrients from the soil, move them throughout the plant, and deposit them in various tissues. A number of unique mechanisms have been identified and differences in the ways that plants control these mechanisms have been noted, both between plant types and within a given plant. Understanding how these differences are achieved will enable scientists to manipulate crop plants, with the goal of enhancing the micronutrient content of edible foods. Improving the nutritional quality of our food supply will be of special benefit to people suffering from micronutrient deficiencies.
Technical Abstract: Plants have developed a number of transport mechanisms to control the acquisition, partitioning and deposition of the micronutrients, iron, copper, zinc and manganese. This control is important because the plant must obtain adequate levels of these essential nutrients for both vegetative and reproductive tissues, while at the same time preventing excess accumulation. Points of physiological control include various root system processes, movement and partitioning along the xylem pathway, temporary storage in vegetative compartments, and remobilization via the phloem pathway. The regulation of these control points is not fully understood, although it appears that certain functions may be influenced by inter-organ communication. Current evidence does indicate that these processes can be controlled to various degrees; differences exist not only between species, they can also vary temporally and spatially within a given nplant. Because this regulatory variability exists, it would appear that enhancing the micronutrient density of edible plant components through the manipulation of physiological processes is an achievable goal.