Arsenic toxicity in crop plants: approaches for stress resistance

Abstract

Heavy metals have been consistent source of environmental pollution. Among all the heavy metals, arsenic (As), a non-essential element for plants, is one of the major pollutants affecting human life. Arsenic exists in three major forms, arsenate (AsV), arsenite (ASIII) and as methylated species. These forms are taken up by different mechanism and mobilized inside the plants. The causes of arsenic toxicity are mainly due to interference in ATP synthesis and alteration in protein structure and catalytic properties. Plants detoxify arsenic largely by complexation with phytochelatins and/or vacuolar sequestration. Existence of genetic variation in different germplasm of crop cultivars with respect to arsenic accumulation offers hope for classical breeding strategies to develop arsenic-tolerant crop cultivars. In this chapter, along with how arsenic is being taken up and metabolized inside the plants, we also discuss the different ways of detoxification of this major heavy metal pollutant.