M.A. Rauf
Soil Resources Development Institute, Krishi Khamar Sarak, Farmgate Dhaka- 1215, Bangladesh
M. A. Hakim
Institute of Tropical Agriculture, Unversiti Putra Malaysia, 43400 UPM Serdang, Selangor DE, Malaysia
M. M. Hanafi
Institute of Tropical Agriculture, Unversiti Putra Malaysia, 43400 UPM Serdang, Selangor DE, Malaysia
M.M. Islam
Dept. of Forest Management, Faculty of Forestry, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia.
G.K.M.M. Rahman
Dept. Soil Science, Bangabandhu Sheikh Mujibur Rahman Agricultural University, Gazipur, Bangladesh
G.M. Panaullah
Bangladesh Rice Research Institute, Gazipur, Bangladesh
Soil, BRRI dhan 33, BR11, Arsenic accumulation, Bioconcentration, Translocation
Net house, Bangabandhu Sheikh Mujibur Rahman Agricultural University (BSMRAU), Gazipur
Crop-Soil-Water Management
Experimental site - The pot experiment was conducted at net house, Bangabandhu Sheikh Mujibur Rahman Agricultural University (BSMRAU), Gazipur. The net house area belongs to the Madhupur Tract (AEZ 28) having 24º 02´ 131" N latitude and 90º 23´ 810" E latitude, 8.4 m AMSL. It is sub-tropical humid climate and is characterized by high temperature accompanied by moderately high rainfall during kharif (April to September) season and low temperature in rabi (October to March) season. Experimental materials and treatments - The growth media prepared with soils contaminated with different levels of As which were: T1 (3.2 ppm), T2 (11.6 ppm), T3 (18.7 ppm), T4 (38.6 ppm), T5 (57.8 ppm) and T6 (80.3 ppm). Among them four elevated arsenic contaminated soils T3 (18.7 ppm), T4 (38.6 ppm), T5 (57.8 ppm) and T6 (80.3 ppm) were collected from STW irrigated area and one background soil (11.6 ppm As) collected from non-irrigated area of Komorpur, Faridpur Sadar Upazila. Another check soil (historically non-contaminated area), having soil As concentration of 3.2 mg kg-1, was collected from BSMRAU campus, Gazipur. The soil was high to medium high land of Tejgaon series in Madhupur Tract. The treatments were arranged in a completely randomized design (CRD) with 6 replications. Plant materials, Planting / sowing and fertilization - Two rice cultivars, BRRI dhan33 and BR11, having the cropping periods of 118 and 145 days, respectively were planted in 'Aman' season. Two healthy and vigor seedlings were transplanted per hill. Accordingly, two hills were received in each pot of 30 cm deep and 12.5 cm diameter plastic pot, containing 15 kg air dried soil. Water requirement was monitored visually. Pre-tested As free (below detection limit) irrigation water was applied in each pot of the experiment almost every day as recommended. The fertilizer doses were followed AEZ 12 as per fertilizer recommendation guide. Therefore, N, P, K, S and Zn were applied at the rate of 66, 6, 12, 7 and 1 kg ha-1 (1.08, 0.23, 0.18, 0.29 and 0.021 g pot-1) from urea, TSP, MP, gypsum and zinc sulphate fertilizer, respectively. Weeding was done manually by hand, when required. Diseases and pest infestations were monitored and necessary steps taken during the total growing period. Arsenic and P accumulation in straw, husk, and grain of Transplant Aman were recorded properly. Plant and soil sampling and chemical analysis - Plant samples collected after harvest and soil samples were collected before and after harvest and analyzed following standard laboratory methods. Mechanical analysis was done by hydrometer method. The pH was determined by the Metrohm 691 digital pH meter. Organic carbon was determined by Leco apparatus. Kjeldahl method was followed for the determination of total nitrogen. Available P of Faridpur soil was extracted with 0.5 M NaHCO3 extracting solution since pH value of the soil was greater than 6.5 (pH>6.5) but the Gazipur soil was extracted with 0.03M NH4F-0.025M HCl since it was below 6.5. The ammonium acetate extraction method was followed for available potassium determination. The contents of K in the soil were directly measured by the Flame Emission Spectrophotometer Available S content was determined by extracting the soil with CaCl2 (0.15%) solution. Available Zn, Cu, Fe, and Mn contents in soil were determined by DTPA extraction method as described by Hunter. The DTPA extractable elements were measured by Atomic Absorption Spectrometer (AAS) using air-acetylene flame and matrix matched standards. The total arsenic content was determined by flow-injection hydride-generation atomic absorption spectroscopy (FI-HG-AAS), using a Perkin Elmer Analyst 200, digestion made by HNO3.H2O2. Plant samples were also digested with conc. HNO3 and 30% H2O2 and determined total As and P in straw, husk and grain as above methods. Bioconcentration factor (BCF) and translocation factor (TF) - The plant’s ability to accumulate metals from soils and their translocation ability from roots to shoots can be estimated using the bioconcentration factor (BCF) and translocation factor (TF), respectively. Statistical Analysis - Statistical analysis was done following MSTAT-C program to find out the effect of each treatment on As and P accumulation in straw, husk and grain and to compare the parameters between the treatments. The means of each treatment was compared by DMRT. Computation and preparation of graphs were done using Microsoft EXCEL 2003 program.
AJCS 5(12):1678-1684(2011); ISSN:1835-2707
Journal