Growth, Yield and Grain Arsenic Concentration of Rice Cultivars under Varying Levels of Soil Arsenic Contamination

Abstract

Arsenic (As) contamination in groundwater is a severe and widespread problem in Bangladesh and their exposure cause a serious health hazard in human history. A pot experiment was conducted in the net-house of the Department of Soil Science, Bangladesh Agricultural University, Mymensingh using fourteen cultivars of rice (Summer rice) to evaluate the effects of varying levels of As contamination on growth, yield and grain As contents. Arsenic contamination adversely affected tillering, filled grains, grain yield and straw yield of all rice cultivars, however, the effect varied among the cultivars. In As control treatment, the highest grain yield (75.66 g pot-1) was observed in BR 11 while the lowest grain yield (8.73 g pot-1) was in BRRI dhan4. Application of 20 ppm As to the soil resulted in complete death of BR 11, BRRI dhan30, BRRI dhan33, BRRI dhan34, BRRI dhan41, Binadhan-4, Biroy and Kalizeera cultivars. Arsenic contamination significantly increased As concentration in grain for all cultivars of rice. Arsenic concentration on rice grains grown in soils without As contamination ranged from 0.06 ppm in BR 11 to 0.13 ppm in BRRI dhan32 and BRRI dhan41, while such values ranged from 0.231 ppm in Kalizeera with 10 ppm As to 0.743 ppm in BRRI dhan40 with applied 20 ppm As to soils. Among the 14 rice cultivars BRRI dhan32, BR 11 and Najirshail appeared to be more tolerant to As contamination.