Screening of Arsenic toxicity in <i>Oryza sativa</i> L. (rice) and assessment of variation in growth, ROS, and antioxidant responses in tolerant and sensitive rice cultivars

ABSTRACT Arsenic (As) in rice plants has toxic effects on their quality and human health. In the present study, 100 rice cultivars have been screened in hydroponics to analyze As toxicity and select As‐tolerant and sensitive rice cultivars. The findings showed that rice cultivars responded differently to As stress at varying levels of effect. As treatments significantly changed morphological traits, the arsenic tolerance index (ATI %), pigments, and H 2 O 2 concentrations. The rice cultivars Luit and Swarna demonstrated remarkable results (tolerant and sensitive) in terms of growth, as well as in terms of ATI, chlorophyll content, H 2 O 2 content, and enzymatic and non‐enzymatic antioxidants. Arsenic‐induced pigment degradation and antioxidant content reduction were greater in Swarna than in Luit. Moreover, the results of biochemical analysis correlated with the morphological parameters. The selected As‐tolerant and sensitive cultivars may be used to explore the tolerance mechanism in greater depth, which will require further molecular investigations.