ABSTRACT
Iron is a micronutrient which is considered essential for plants to carry out physiological processes such as photosynthesis, respiration, oxygen transport, oxygen metabolism, DNA and RNA synthesis, cellular proliferation, electron transfer, etc. Although iron is present in bulk amounts on the surface of the earth, but still, it is not available in soil for plants. Iron solubility is very low under aerobic conditions because of the prevalence of ferric ions (Fe3+ ), which are generally found as oxihydroxide polymers, particularly in calcareous soils, affecting the iron supply for plant uptake. Increased amount of ferrous ions (Fe2+ ) is generated in flooded soils, i.e., in anaerobic and acidic soils, by the reduction of iron oxides (Fe3+ ) leading to Fe toxicity due to iron uptake in excess amount. This iron toxicity affects the plant growth and agricultural productivity hampering the potential of plants in terms of plant uptake and resulting in slow growth rate and low biomass. Therefore, an efficient strategy for iron uptake by plants is the secretion of microbial phytosiderophores. Recently, plant-based techniques such as phytoremediation/bioremediation were considered as environmentally friendly and low-cost technologies to clean iron-polluted soils via plant breeding, plant volatizing, and plant extraction. Biofortification and bioremediation are closely connected similar to the two sides of a coin. Therefore, this chapter 278deals with the transgenic technology that increases the iron accumulation in plants or staple crops, thereby using it for both biofortification and simultaneous bioremediation of iron.
