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Aims: The objectives of this experiment was to establish initial steps of somatic embryogenesis from the fu sed protoplasts between two Brassica species: Brassica rapa L. (var. Agrani, AA, 2n=20) and Brassica juncea L. (var. BINA Sharisha - 7 and var. BINA Sharisha - 8, AABB, 2n=36). Study Design: The experiment was carried out in completely randomized design with t hree replications for each hormone treatment of each variety combination. Place and Duration of Study: An experiment was conducted in growth room of tissue culture laboratory at the Department of Genetics and Plant Breeding, Bangladesh Agricultural Univers ity, Mymensingh during the period from April, 2013 to May, 2014. Methodology: Mesophyll protoplasts were isolated from the young leaves of aseptically grown plants. Variety combinations for protoplasts fusion were: Agrani+BINA Sharisha - 7 and Agrani+ BINA S harisha - 8. 100% polyethylene glycol - 400 was used as a fusogen. Pellieter different compositions of liquid media were used for protoplasts cultured, microcalli, calli and somatic embryo formation. Results: Fused products were cultured in a modified Pelliet er B liquid media with different

Geochemical composition and the level of Arsenic (As) contamination of groundwater in the Ganges Delta Plain, southwestern Bangladesh were elucidated. Hydrogeochemical data of tube well samples suggested that the groundwater is mostly Ca-Mg-HCO(3) type with bicarbonate (HCO(3)(-)) as the dominant anion, though other type waters are also observed. In contrast, the elevated EC, Cl(-) and high content of Na(+) relative to Ca(2+), Mg(2+) and K(+) in six groundwater samples suggest their saline origin. Low concentrations of NO(3)(-) and SO(4)(2-), and high concentrations of dissolved organic carbon (DOC), HCO(3)(-) and PO(4)(3-) indicate the reducing conditions of subsurface aquifer where sediments are deposited with abundant organic matter. The total As concentration in the analyzed samples is very high (0.0431-1.352 mg/L) along with high Fe (2.791-17.058 mg/L) and relatively low Mn (0.134-1.972 mg/L) at different depths. Distinct relationship of As with Fe and Mn, and strong correlation with DOC suggests that the biodegradation of organic matter and reductive dissolution of Fe-oxyhydroxide is considered to be the dominant processes to release As in aquifers. Moreover, negative correlation between As and SO(4)(2-) demonstrates the As may not be directly mobilized from sulfide minerals like arsenopyrite.