The pot experiment was conducted at the net house, Department of Soil Science, Bangabandhu Sheikh Mujibur Rahman Agricultural University (BSMRAU), Gazipur, Bangladesh. This experiment site enjoys good sunshine throughout the day. The climate of this area is sub-tropical, characterized by high temperatures during April– August, high rainfall during the monsoon season (June-August), and low temperatures during winter (November–February). Though the experiment was conducted in a net house, normal environmental conditions were maintained inside the net house. Soils were collected from the BSMRAU Research field at a depth of 0-15 cm. Soils were stacked in the net house and air-dried. Prior to potting, soils were ground and mixed thoroughly. For determining initial soil As content, physical and chemical properties, 20 samples were made from different sites of a soil stack. These dried soil samples were further ground to pass through a 2- mm sieve for analysis of physical and chemical properties of soil as per standard protocols and pass through a 100 µm sieve for initial As content determination. Soil pH, organic carbon, total N, available P, exchangeable K, available S, and Available Zn were analyzed. The moisture content of selected soil samples was determined by the gravimetric method. Initially, each pot was filled with 10 kg of dry soil followed by the addition of soil test-based fertilizer. Pot soil was flooded with water and kept it standing overnight. On the following day, Sodium Arsenate (Na2HAsO4.7H2O) at 0, 20, 40, and 60 mg/ kg (oven-dry soil basis) was mixed. After mixing sodium arsenate with soil, pots were kept standing for three days without irrigation prior to transplanting. As free tap water was used to soften the pot soils prior to transplanting. Forty days-old Boro and 30 days-old T. Aman seedlings were used at two seedlings/pot. About 3–4 cm water level was maintained above pot soil from transplanting to physiological maturity with As free tap water. Topdressing and other intercultural operations were done during the growing season. Sixteen rice varieties including Bangladeshi and exotic (Chinese, IRRI, and USA) were used as test varieties (eight genotypes in each season). Four levels (0, 20, 40, and 60 mg/kg) of As concentration was spiked using sodium arsenate in the present research. All plants grown in each pot were removed separately for biomass, straw, and grain yield. Grain and straw of all rice varieties were air-dried. The straw yield was recorded after oven drying at 70ºC for 72 hours. Grain yield per pot at 14% moisture content was also recorded. Straw was then chopped into smaller sizes (5-7 cm). All chopped plant samples were oven-dried, ground, and homogenized with Vibrating Sample Mill, HEIKO TI-200, and kept for total As measurement using HG-AAS machine. Straw and rice flour samples were digested by modified nitric (HNO3)-perchloric (HClO4) acid digestion [26] with block digester (Model-VELP). The block digester consists of 24 blocks of which one for standard reference materials (SRM), one for blank, one for duplicate sample, and 21 were used for sample digestion. Prior to digestion, overnight pre-digestion was followed with nitric acid for total As analysis. After pre-digestion, samples were heated for one hour followed by the addition of perchloric acid and digestion continued up to four hours. After cooling, the digest was diluted to 50 ml in a volumetric flask. Samples were filtered through Whatman 42 filter paper prior to total As analysis. In rice flour digestion, the SRM was used to compare the certified value of 0.29 ± 0.03 mg/kg. In the case of straw digestion, the secondary reference material (SeRM) was used. The recovery percentage of digestion of SRM and SeRM at 90% and above was considered As the accepted range. Spectrophotometer Straw and rice flour digests were treated with 5% potassium iodide and ascorbic acid to reduce As (V) to As (III) for determination of As by hydride generation atomic absorption spectrophotometer (HG-AAS), Buck Scientific 210 VGP continuous flow hydride generation system (HG-AAS). Prior to pre-reduction, samples were acidified by concentrated hydrochloric acid (HCl). Sodium borohydride (NaBH4, 0.5%) and 3M HCl was used at sample injection time to generate hydride of As (arsine, AsH3). The acidified sample and the reductant (NaBH4) solutions were taken in suitable mixed in a reaction coil, and the gaseous hydride was separated and swept by argon (Ar) gas into a heated silica tube aligned in the optical path of the spectrophotometer. The wavelength used for As analysis was 193.7 nm. The standards were prepared following the same analytical matrix of sample preparation and used for the generation of the standard calibration curve. Statistical analyses were performed using statistics 10 software. Regression analysis was done to establish the relationship between As concentration in straw and rice grain. The relationship of concentration in straw and grain with straw and grain yield reduction percentages was also established.