Being a toxic metalloid and group I carcinogen, Arsenic (As) poses a threat to plants, especially to crops which are consumed by human beings, and sooner or later results in hyper/hypopigmentation and skin cancer. It is a well‐known fact that South‐East Asia is suffering from groundwater As contamination, and according to a recent report, the contamination has been found also in Hungary, Mexico, Argentina, Australia, United States, etc. Thus, As contamination has become a global problem. As is toxic even at low concentration because it has no known function as nutrients. Arsenite (III) and arsenate (V) are the main phytoavailable forms of inorganic arsenic. Being analogous to phosphate, As(V) is transported by a phosphate‐cotransport system in plants, whereas As(III) is transported through ‘OsNIP2.1’ (member of aquaporin superfamily) in rice. Besides, ‘AsSe1’ (As‐accumulation gene), ‘AsTol’ (As‐tolerance gene) and ‘OsACR2.1’ (an arsenate reductase gene) have also been identified. The production of phytochelatins (PCs), a metal‐binding thiol peptide, in response to As stress may hold a way of proper As tolerance in plants but still needs a thorough study. However, with the proper knowledge of arsenic speciation, transportation, accumulation, overexpression in crop plants may result in ways to develop arsenic tolerant transgenics.

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Cadmium (Cd) is a potential environmental phytotoxicant. The generation of reactive oxygen species (ROS) due to Cd stress is responsible for the induction of oxidative stress in plants. On the other hand, SNP, a NO donor is known to have effect on Cd-induced oxidative stress in plants. We evaluated the effect of NO on the regulation of Cd stress in the rice (Oryza sativa L.) variety MSE-9. Cd treatment was given in the form of 50, 100 and 200 lM, whereas for interaction study, 100 lM of Cd and 100 lM of SNP were used. The result showed that Cd-induced oxidative stress in MSE-9 by generating ROS. However, when SNP was given with Cd stress, it was seen that SNP treatment regulated the stress metabolism in rice seedlings under Cd toxicity by generating NO. It can be said that the SNP in combination with Cd treatment might possess the way to protect rice seedlings under Cd stress.