Arsenic-induced morphological variations and the role of phosphorus in alleviating arsenic toxicity in rice (Oryza sativa L.)

Primarily, this study was conducted to screen for As tolerant rice genotypes based on morphophysiological features. Root length and root fresh weight significantly reduced in BRRI-39, BRRI-41, and BRRI-51 due to As treatment compared to controls excluding BRRI-33. Further, BRRI-33 did not show a significant decrease in shoot height and shoot fresh weight due to As treatment; whereas these parameters were severely affected by the same conditions in other genotypes. It does suggest that BRRI-33 can tolerate As and its growth parameters are not affected by As treatment. In contrast, BRRI-39, BRRI-41, and BRRI-51 are sensitive to As. Secondly, As and P supplementation significantly increased chlorophyll concentrations in BRRI-33, BRRI-44, and BRRI-51 but not in BRRI-39 compared to controls and As-treated plants. Again, As and P treatment significantly increased the root and shoot dry weight in BRRI-33 and BRRI-44 compared to As-treated plants. Finally, dual treatment of As and P significantly decreased the As concentration in leaves of BRRI33, BRRI-44, and BRRI-51 but not in BRRI-39. It suggests that P is involved in alleviating As toxicity and inhibiting As uptake in leaves of rice. Among them, BRRI-33 is most efficient in utilizing P in alleviating As toxicity.