Relative Toxicity of Arsenite and Arsenate on Early Seedling Growth and Photosynthetic Pigments of Rice

Arsenic is a potential contaminant of groundwater as well as soil in many regions of the world. Elevated soil arsenic levels resulting from long-term use of arsenic contaminated ground water for irrigation may inhibit seed germination and seedling establishment of rice, the country’s main food crop. An experiment was conducted to study the effect of different forms of arsenic on growth and photosynthetic pigments of rice plants. For this purpose rice seedlings were grown hydroponically with half strength of modified Hoagland nutrient solution toxified with different doses of arsenate and arsenite namely 0, 5, 10, 15 and 20 ppm. Germination percent of rice seeds and photosynthetic pigment content of rice seedling decreased significantly with increase in concentration of arsenic of both the forms. Growth parameters affected more seriously in arsenite treated plants than arsenate treated plants.