Comprehensive Overview of Iron Nutrition and Deficiency: Uptake, Transport and Metabolism in Legumes

Legumes are important sources of nitrogen and, therefore, the nitrogen fixing ability of the legume-rhizobia symbiosis has great potential to improve crop yields or reduce nitrogen fertilizer use. Unfortunately, legumes face serious and increasing threats of both biotic and abiotic stresses among which Fe-deficiency has been increased from past years. Fe nutrient deficiency limits pulse production and nitrogen fixation by specifically affecting any one of the four phases of legume-rhizobium symbiosis. Although Fe in soil is often present in adequate quantities, it is mainly present in insoluble Fe-(III) precipitates, limiting its uptake and utilization. The present review has focused on the iron nutrition and deficiency and probable uptake, transport and metabolism in legumes.