Phytoremediation Using Leguminous Plants: Managing Cadmium Stress with Applications of Arbuscular Mycorrhiza (AM) Fungi

Legumes are the part of crop-rotation to enrich soil mineral availability naturally for the legumes itself and successive nonleguminous crop. The fixation of abundant but chemically inert molecular nitrogen is brought about by the important symbiosis of roots of legumes with Rhizobium present in the soil. Pulses are the major group of leguminous plants cultivated for edible grains besides other economically important parts. Application of pesticides in the arable lands has been a well-recognized cause of increasing anthropogenic rise of soil cadmium level. Cadmium (Cd) is a highly toxic, nonessential heavy metal which significantly disturbs the metabolism, physiological processes, growth, and yield of crop plants. Plants deploy various mechanisms to cope up Cd-induced toxicity, hence categorized accordingly. In legumes Cd has been reported to disturb soil microbial population and its symbiotic relation with legumes root system. This leads to declined growth performance and productivity of pulses. Alternatively, mycorrhizal web associated with plant root system could work as a sieve for Cd filtration, discouraging its entry into plant tissues and allowing other minerals and organic substances along with restoring water status. This chapter focuses on how interaction of arbuscular mycorrhizal (AM) fungi with root augments performance of legumes growth and signifies its practical applicability in the Cd polluted arable lands.