Dr. M. Rafiqul Islam - Academia.edu (original) (raw)

Papers by Dr. M. Rafiqul Islam

Research in Agriculture Livestock and Fisheries, 2015

during July to December 2013 in the aman season to investigate the effect of age of seedling and ... more during July to December 2013 in the aman season to investigate the effect of age of seedling and nitrogen rates in the nursery bed on growth, yield and yield components of BRRI dhan52. The experiment comprised of three ages of seedlings viz., 30, 35 and 40 day old and four nitrogen rate N 1-N@50 kg ha-1 , N 2-N@75 kg ha-1 , N 3-N@100 kg ha-1 , N 4-N@125 kg ha-1. The experiment was laid out in a split plot design with three replications. Age of seedling showed significant differences for shoot weight, survivor, no. grains panicle-1 , panicle length, grain yield and straw yield. The highest root weight (0.072 gm-2), plant height (108 cm), total tillers hill-1 (8.22), effective tillers hill-1 (7.03), non-effective tillers hill-1 (1.19), survivor (95.1%), grains panicle-1 (106.2), grain yield (5.57 t ha-1), straw yield (6.26 t ha-1) and harvest index (0.47%) were found by transplanting 40 day old seedlings. The highest shoot weight (0.53 gm-2), 1000 grain wt. (25.3g) was found by transplanting 35 day old seedlings and 30 day old seedlings produced highest sterile spikelets (28.9) and panicle length (23.8 cm). Nitrogen rate in the nursery showed significant differences for shoot weight, root weight, survivor, plant height, total tillers hill-1 , effective tillers hill-1 , non-effective tillers hill-1 , panicle length, grains panicle-1 , grain yield and straw yield. Application of 50 kg N ha-1 gave higher plant height (108 cm) and harvest index (0.47%). On the other hand, application of 75 kg N ha-1 produced highest non-effective tillers hill-1 (1.0), grains panicle-1 (100.7), 1000 grain weight (25.3 g) and harvest index (0.47%). Application of 100 kg N ha-1 gave highest total tillers hill-1 (7.85), effective tillers hill-1 (6.85), non-effective tillers hill-1 (1.0), survivor (90.5%) and grain yield (5.01 t ha-1). Application of 125 kg N ha-1 gave highest panicle length (23.75 cm), grains panicle-1 (100.7), non-effective tillers hill-1 (1.0) and sterile spikelets (30.1). Forty day old seedlings grown with 100 kg N ha-1 at nursery found to be better in respect of grain yield. The result of the experiment also showed that aged seedlings regenerated quickly after desubmerge of water.

Journal of the Bangladesh Agricultural University, 2014

A field experiment was conducted at the Soil Science Field Laboratory of Bangladesh Agricultural ... more A field experiment was conducted at the Soil Science Field Laboratory of Bangladesh Agricultural University (BAU), Mymensingh during Aman season of 2011 to evaluate the effects of manures and fertilizers for maximizing the yield of BRRI dhan49. The experiment had six treatments, laid out in a randomized complete block design (RCBD) with four replications. The treatments were T0 = Control, T1 = STB-CF (HYG), T2 = CD + STB-CF (HYG), T3 = PM + STB-CF (HYG), T4= CoM + STB-CF (HYG) and T5 = Farmers’ practice (FP). Organic manures including cowdung, poultry manure and compost were applied to the experimental plots @ 5, 3 and 5 t ha-1, respectively. The recommended dozes of N, P, K and S supplied from urea, TSP, MoP and gypsum were 90, 15, 60 and 15 kg ha-1, respectively. Yield contributing characters like plant height, effective tillers hill-1, panicle length and grains panicle-1 of BRRI dhan49 were significantly influenced by the application of manures and fertilizers. The highest grain ...

Asian Journal of Soil Science and Plant Nutrition

Arsenic (As) contamination in groundwater is a severe and widespread problem in Bangladesh and th... more 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...

Improved soil fertility is a precondition for increased crop production. Soil organic matter is a... more Improved soil fertility is a precondition for increased crop production. Soil organic matter is a key factor in maintaining long-term soil fertility since it is the reservoir of metabolic energy, which drives soil biological processes involved in nutrient availability. Field experiments were conducted over three years during 2005 to 2007 at Bangladesh Agricultural University farm, Mymensingh, Bangladesh, using maize-legume-rice cropping pattern to see the effect of inorganic fertilizers along with organic manure and mungbean residue on soil properties and crop yields. For the first crop (maize), there were five treatments. After maize, seeds of mungbean and dhaincha (Sesbania) were sown as per treatments as legume crop. For rice (third crop), each of the treatments (T2 and T3 plots) were subdivided into six, so there were altogether 15 treatments. Integrated use of manure and inorganic fertilizers or Integrated Plant Nutrient System (IPNS) basis produced comparable seed yield of maize with the chemical fertilizers alone irrespective of moderate or high yield goal basis. The incorporation of Sesbania biomass and mungbean residue along with inorganic fertilizers for moderate yield goal produced identical grain yields of rice compared to fertilizers applied for high yield goal. After three years of cropping, the nutrient status of soils in control, fallow and mungbean residue removal plots showed a decreasing trend while incorporation of Sesbania biomass and mungbean residue had a positive effect on soil fertility. Therefore, addition of mungbean residues or Sesbania biomass to the fertilizer schedule ensures higher crop productivity and sustains soil fertility in maize-legume-rice cropping pattern.

Legume Research - An International Journal, 2014

The pot experiment was conducted to the peat-based Bradyrhizobium inoculants as biofertilizer for... more The pot experiment was conducted to the peat-based Bradyrhizobium inoculants as biofertilizer for cultivation of indigo (Indigofera tinctoria L.). Six isolates of Bradyrhizobium of indigo origin (HSTU-IR2, HSTU-IR3, HSTU-IR4, HSTU-IR9, HSTU-IR10 and HSTU-IR14) were collected from the

Journal of the Faculty of Agriculture, Kyushu University

Pakistan Journal of Biological Sciences, 2001

during the Aman season of 1999 to evaluate the effect of manures and fertilizers on the growth an... more during the Aman season of 1999 to evaluate the effect of manures and fertilizers on the growth and yield of BRRI Dhan 30. The experiment was laid out in Randomized Complete Block Design with three replications. There were seven treatments such as T 0 (control), T 1 (N 100), T 2 (N 100 S 10 Zn 5), T 3 (PM 5), T 4 (PM 7.5), T 5 (PM 10) and T 6 (CD 10). The results demonstrated that all the treatments had positive effect on the yield components and yields of BRRI Dhan 30. Grain and straw yields of BRRI Dhan 30 were significantly increased due to different treatment and the highest value was recorded with the application of poultry manure at 10 t haG 1. The NPKS content in BRRI Dhan 30 and their uptake were increased due to the application of manures and fertilizers. Analysis of post-harvest soils revealed that organic manure application had a positive influence on organic matter, total N, available P, exchangeable K, available S and CEC of the post-harvest soils.

Exposure and Health

In Bangladesh most agronomic biomass (straw, husk, dried dung) is burnt for domestic cooking use.... more In Bangladesh most agronomic biomass (straw, husk, dried dung) is burnt for domestic cooking use. Consequently, the soil is continuously stripped of mineral nutrients and carbon (C) substrate. Here we investigate if recycling of household ash (ash) as fertilizer can sustainably improve soil fertility as well as minimise accumulation of toxic elements (As, Cd) in rice grain. Large scale field trials across two geographic regions (Barind, Madhupur) and two seasons (wet, dry) and with application of 3 fertiliser treatments (NPKS, ash, NPKS + ash) were conducted. At the end of each season, the impact of region*season*treatment on soil microbial comunities, rice yield, and grain quality (As, Cd, nutrient elements) was assessed. When compared to conventional field application rates of NPKS (control), application of ash boosted rice yield by circa. 20% in both regions during wet and dry season, with no effect on rice grain carcinogenic inorganic arsenic (iAs), dimethylarsonic acid (DMA) or...

European Journal of Agriculture and Food Sciences

Reducing methane (CH4) emissions and water use in irrigated rice systems while maintaining produc... more Reducing methane (CH4) emissions and water use in irrigated rice systems while maintaining production to feed the ever-increasing population is vital in Bangladesh. Different rice establishment methods viz. alternate wetting & drying (AWD), system rice intensification (SRI) and direct wet seeded rice (DWSR), have a promising mitigation potential to reduce CH4emission compared to continuous flooded (CF) rice fields. A field experiment was conducted at Bangladesh Agricultural University, Mymensingh, during the Boro season in 2018 to examine whether rice establishment methods could maintain grain yield with reduced water use and CH4emissions. A split-plot design was employed with water management in the main plots and fertilizer management in the subplots. The yield difference was not significant (p>0.05) in CF, AWD, and SRI systems other than DWSR. Planting methods in combination with organic fertilizer amendment had little effect on the grain Fe, Zn, and Cd concentration but signi...

Exposure and Health

Despite the centrality of staple grains for human well-being, both as a source of nutrients and o... more Despite the centrality of staple grains for human well-being, both as a source of nutrients and of toxic ions, there is little understanding of where and how elements vary, and if there are particular elements that correlate. Here, for shop bought polished (white) rice, we comprehensively characterized trace (arsenic species, cadmium, copper, iron, manganese, molybdenum, rubidium and zinc) and macro-nutrients (calcium, chlorine, potassium, phosphorus and sulphur) for grain purchased in 18 countries, across four continents, a total of 1045 samples. This was to investigate if there were any major differences between geographic location and elemental content, and to observe if there were any patterns in elemental distribution. Greatest variation in the median was observed for the non-essential rubidium (15-fold) and arsenic species (fivefold). Rubidium was the highest in the Americas, lowest in Europe, while inorganic arsenic (iAs) and dimethylarsonic acid (DMA) were low for Africa and...

Land, 2021

Minimum soil disturbance and increased crop residue retention practices are promising options to ... more Minimum soil disturbance and increased crop residue retention practices are promising options to enhance soil organic matter, nutrient concentration and crop yield. However, the potentials of the practices in improving soil properties, increasing crop yield and in ensuring economic return have not been tested in the monsoon rice (Oryza sativa L.)-lentil (Lens culinaris L.)/wheat (Triticum aestivum L.)-jute (Corchorus culinaris L.) cropping systems on seasonally flooded lowlands of the Eastern Gangetic Plain of South Asia. A field trial for consecutive three years was conducted in the Gangetic Plains of Bangladesh to evaluate the effects of zero tillage (ZT), strip-tillage (ST), bed planting (BP) and conventional tillage (CT) with two residue retention levels (RL—a low level similar to current farmers’ practice and RH—increased retention) on soil properties, yield and economic return. Between rice and jute crops, lentil was grown for the 1st and 2nd years and wheat for the 3rd year d...

Despite the centrality of staple grains for human well-being, both as a source of nutrients and o... more Despite the centrality of staple grains for human well-being, both as a source of nutrients and of toxic ions, there is little understanding of where and how elements vary, and if there are particular elements that correlate. Here, for shop bought polished (white) rice we comprehensively characterize trace (arsenic species, cadmium, copper, iron, manganese, molybdenum, rubidium and zinc) and macro-nutrients (calcium, chlorine, potassium, phosphorus and sulphur) for grain purchased in 18 countries, across 4 continents, a total of 1045 samples, to investigate if there were any major differences between geographic location and elemental content, and to observe if there were any patterns in elemental distribution. Greatest variation in the median was observed for the non-essential rubidium (15-fold) and arsenic species (5-fold). Rubidium was highest in the Americas, lowest in Europe, while inorganic arsenic and dimethylarsonic acid (DMA) were low for Africa and high in the South America...

European Journal of Agriculture and Food Sciences, 2021

Zinc (Zn) deficiency is widespread nutrient disorder in lowland rice growing areas in Asia, espec... more Zinc (Zn) deficiency is widespread nutrient disorder in lowland rice growing areas in Asia, especially in Bangladesh. Intensive cropping with modern varieties causes depletion of inherent nutrient reserves in soils. The application of Zn fertilizers results in higher crop productivity and increases Zn concentration in crops. A field experiment was conducted to evaluate the effect of Zn application on growth, yield, and grain-Zn concentration in eight varieties of rice. The experiment was laid out in a split plot design with a distribution of Zn rates (0 kg ha-1 and 3 kg ha-1 from ZnO) to the main plots and rice varieties (BRRI dhan49, BRRI dhan52, BRRI dhan56, BRRI dhan57, Kalizira, Biroin, Gainja and Khirshapath) to the sub-plots. Zinc application improved effective tillers hill-1, grains panicle-1 and 1000-grain weight which impacted the grain yield of rice. Among the eight rice varieties, a significant increase of grain yield was recorded in BRRI dhan49, BRRI dhan52, BRRI dhan56 ...

Exposure and Health, 2020

One of cadmium’s major exposure routes to humans is through rice consumption. The concentrations ... more One of cadmium’s major exposure routes to humans is through rice consumption. The concentrations of cadmium in the global polished (white), market rice supply-chain were assessed in 2270 samples, purchased from retailers across 32 countries, encompassing 6 continents. It was found on a global basis that East Africa had the lowest cadmium with a median for both Malawi and Tanzania at 4.9 μg/kg, an order of magnitude lower than the highest country, China with a median at 69.3 μg/kg. The Americas were typically low in cadmium, but the Indian sub-continent was universally elevated. In particular certain regions of Bangladesh had high cadmium, that when combined with the high daily consumption rate of rice of that country, leads to high cadmium exposures. Concentrations of cadmium were compared to the European Standard for polished rice of 200 μg/kg and 5% of the global supply-chain exceeded this threshold. For the stricter standard of 40 μg/kg for processed infant foods, for which rice ...

Environmental Science & Technology, 2019

Fundamental and Applied Agriculture, 2018

Journal of the Bangladesh Agricultural University, 2010

A study was made on the effect of arsenic (As) and As X P interaction in Boro rice and its residu... more A study was made on the effect of arsenic (As) and As X P interaction in Boro rice and its residual effect in succeeding T. Aman rice. Arsenic was added to soil (having 2.6 ppm initial As) @ 0, 15 and 30 mg As kg -1 from Na2HAsO4.7H2O and phosphorus @ 0, 20, 40, 60 and 80 mg P kg-1 from KH2PO4. Each pot had received 100 ppm N, 40 ppm K and 25 ppm S from urea, MoP and gypsum, respectively. The grain yield of Boro rice was reduced by 20.6 % for 15 ppm As treatment and 63.8 % due to 30 ppm As. Such reductions for straw yield were 21.0 and 65.2 % with these two As treatments, respectively. Residual effect of arsenic was also significant and negative in T. Aman rice. The grain-As concentration in all cases was below 1 ppm, and the straw-As content was well above 1 ppm. The arsenic concentrations of both grain and straw were lower in T. Aman rice than in Boro rice. The adverse effect of arsenic was further enhanced by P addition. This reaction has an implication to P fertilizer management...

New Phytologist, 2011

• Inorganic arsenic (As i) in rice (Oryza sativa) grains is a possible threat to human health, wi... more • Inorganic arsenic (As i) in rice (Oryza sativa) grains is a possible threat to human health, with risk being strongly linked to total dietary rice consumption and consumed rice As i content. This study aimed to identify the range and stability of genetic variation in grain arsenic (As) in rice. • Six field trials were conducted (one each in Bangladesh and China, two in Arkansas, USA over 2 yr, and two in Texas, USA comparing flooded and nonflood treatments) on a large number of common rice cultivars (c. 300) representing genetic diversity among international rice cultivars. • Within each field there was a 3-34 fold range in grain As concentration which varied between rice subpopulations. Importantly, As i correlated strongly with total As among a subset of 40 cultivars harvested in Bangladesh and China. • Genetic variation at all field sites was a large determining factor for grain As concentration, indicating that cultivars low in grain As could be developed through breeding. The temperate japonicas exhibited lower grain As compared with other subpopulations. Effects for year, location and flooding management were also statistically significant, suggesting that breeding strategies must take into account environmental factors.

Environmental Science & Technology, 2009

An extensive data set of total arsenic analysis for 901 polished (white) grain samples, originati... more An extensive data set of total arsenic analysis for 901 polished (white) grain samples, originating from 10 countries from 4 continents, was compiled. The samples represented the baseline (i.e., not specifically collected from arsenic contaminated areas), and all were for market sale in major conurbations. Median total arsenic contents of rice varied 7-fold, with Egypt (0.04 mg/kg) and India (0.07 mg/kg) having the lowest arsenic content while the U.S. (0.25 mg/kg) and France (0.28 mg/kg) had the highest content. Global distribution of total arsenic in rice was modeled by weighting each country's arsenic distribution by that country's contribution to global production. A subset of 63 samples from Bangladesh, China, India, Italy, and the U.S. was analyzed for arsenic species. The relationship between inorganic arsenic content versus total arsenic content significantly differed among countries, with Bangladesh and India having the steepest slope in linear regression, and the U.S. having the shallowest slope. Using country-specific rice consumption data, daily intake of inorganic arsenic was estimated and the associated internal cancer risk was calculated using the U.S. Environmental Protection Agency (EPA) cancer slope. Median excess internal cancer risks posed by inorganic arsenic ranged 30-fold for the 5 countries examined, being 0.7 per 10,000 for Italians to 22 per 10,000 for Bangladeshis, when a 60 kg person was considered.

Environmental Science & Technology, 2008

Rice is more elevated in arsenic than all other grain crops tested to date, with whole grain (bro... more Rice is more elevated in arsenic than all other grain crops tested to date, with whole grain (brown) rice having higher arsenic levels than polished (white). It is reported here that rice bran, both commercially purchased and specifically milled for this study, have levels of inorganic arsenic, a nonthreshold, class 1 carcinogen, reaching concentrations of ∼1 mg/kg dry weight, around 10-20 fold higher than concentrations found in bulk grain. Although pure rice bran is used as a health food supplement, perhaps of more concern is rice bran solubles, which are marketed as a superfood and as a supplement to malnourished children in international aid programs. Five rice bran solubles products were tested, sourced from the United States and Japan, and were found to have 0.61-1.9 mg/kg inorganic arsenic. Manufactures recommend ∼20 g servings of the rice bran solubles per day, which equates to a 0.012-0.038 mg intake of inorganic arsenic. There are no maximum concentration levels (MCLs) set for arsenic or its species in food stuffs. EU and U.S. water regulations, set at 0.01 mg/L total or inorganic arsenic, respectively, are based on the assumption that 1 L of water per day is consumed, i.e., 0.01 mg of arsenic/ day. At the manufacturers recommended rice bran solubles consumption rate, inorganic arsenic intake exceeds 0.01 mg/ day, remembering that rice bran solubles are targeted at malnourished children and that actual risk is based on mg kg-1 day-1 intake.

Research in Agriculture Livestock and Fisheries, 2015

during July to December 2013 in the aman season to investigate the effect of age of seedling and ... more during July to December 2013 in the aman season to investigate the effect of age of seedling and nitrogen rates in the nursery bed on growth, yield and yield components of BRRI dhan52. The experiment comprised of three ages of seedlings viz., 30, 35 and 40 day old and four nitrogen rate N 1-N@50 kg ha-1 , N 2-N@75 kg ha-1 , N 3-N@100 kg ha-1 , N 4-N@125 kg ha-1. The experiment was laid out in a split plot design with three replications. Age of seedling showed significant differences for shoot weight, survivor, no. grains panicle-1 , panicle length, grain yield and straw yield. The highest root weight (0.072 gm-2), plant height (108 cm), total tillers hill-1 (8.22), effective tillers hill-1 (7.03), non-effective tillers hill-1 (1.19), survivor (95.1%), grains panicle-1 (106.2), grain yield (5.57 t ha-1), straw yield (6.26 t ha-1) and harvest index (0.47%) were found by transplanting 40 day old seedlings. The highest shoot weight (0.53 gm-2), 1000 grain wt. (25.3g) was found by transplanting 35 day old seedlings and 30 day old seedlings produced highest sterile spikelets (28.9) and panicle length (23.8 cm). Nitrogen rate in the nursery showed significant differences for shoot weight, root weight, survivor, plant height, total tillers hill-1 , effective tillers hill-1 , non-effective tillers hill-1 , panicle length, grains panicle-1 , grain yield and straw yield. Application of 50 kg N ha-1 gave higher plant height (108 cm) and harvest index (0.47%). On the other hand, application of 75 kg N ha-1 produced highest non-effective tillers hill-1 (1.0), grains panicle-1 (100.7), 1000 grain weight (25.3 g) and harvest index (0.47%). Application of 100 kg N ha-1 gave highest total tillers hill-1 (7.85), effective tillers hill-1 (6.85), non-effective tillers hill-1 (1.0), survivor (90.5%) and grain yield (5.01 t ha-1). Application of 125 kg N ha-1 gave highest panicle length (23.75 cm), grains panicle-1 (100.7), non-effective tillers hill-1 (1.0) and sterile spikelets (30.1). Forty day old seedlings grown with 100 kg N ha-1 at nursery found to be better in respect of grain yield. The result of the experiment also showed that aged seedlings regenerated quickly after desubmerge of water.

Journal of the Bangladesh Agricultural University, 2014

A field experiment was conducted at the Soil Science Field Laboratory of Bangladesh Agricultural ... more A field experiment was conducted at the Soil Science Field Laboratory of Bangladesh Agricultural University (BAU), Mymensingh during Aman season of 2011 to evaluate the effects of manures and fertilizers for maximizing the yield of BRRI dhan49. The experiment had six treatments, laid out in a randomized complete block design (RCBD) with four replications. The treatments were T0 = Control, T1 = STB-CF (HYG), T2 = CD + STB-CF (HYG), T3 = PM + STB-CF (HYG), T4= CoM + STB-CF (HYG) and T5 = Farmers’ practice (FP). Organic manures including cowdung, poultry manure and compost were applied to the experimental plots @ 5, 3 and 5 t ha-1, respectively. The recommended dozes of N, P, K and S supplied from urea, TSP, MoP and gypsum were 90, 15, 60 and 15 kg ha-1, respectively. Yield contributing characters like plant height, effective tillers hill-1, panicle length and grains panicle-1 of BRRI dhan49 were significantly influenced by the application of manures and fertilizers. The highest grain ...

Asian Journal of Soil Science and Plant Nutrition

Arsenic (As) contamination in groundwater is a severe and widespread problem in Bangladesh and th... more 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...

Improved soil fertility is a precondition for increased crop production. Soil organic matter is a... more Improved soil fertility is a precondition for increased crop production. Soil organic matter is a key factor in maintaining long-term soil fertility since it is the reservoir of metabolic energy, which drives soil biological processes involved in nutrient availability. Field experiments were conducted over three years during 2005 to 2007 at Bangladesh Agricultural University farm, Mymensingh, Bangladesh, using maize-legume-rice cropping pattern to see the effect of inorganic fertilizers along with organic manure and mungbean residue on soil properties and crop yields. For the first crop (maize), there were five treatments. After maize, seeds of mungbean and dhaincha (Sesbania) were sown as per treatments as legume crop. For rice (third crop), each of the treatments (T2 and T3 plots) were subdivided into six, so there were altogether 15 treatments. Integrated use of manure and inorganic fertilizers or Integrated Plant Nutrient System (IPNS) basis produced comparable seed yield of maize with the chemical fertilizers alone irrespective of moderate or high yield goal basis. The incorporation of Sesbania biomass and mungbean residue along with inorganic fertilizers for moderate yield goal produced identical grain yields of rice compared to fertilizers applied for high yield goal. After three years of cropping, the nutrient status of soils in control, fallow and mungbean residue removal plots showed a decreasing trend while incorporation of Sesbania biomass and mungbean residue had a positive effect on soil fertility. Therefore, addition of mungbean residues or Sesbania biomass to the fertilizer schedule ensures higher crop productivity and sustains soil fertility in maize-legume-rice cropping pattern.

Legume Research - An International Journal, 2014

The pot experiment was conducted to the peat-based Bradyrhizobium inoculants as biofertilizer for... more The pot experiment was conducted to the peat-based Bradyrhizobium inoculants as biofertilizer for cultivation of indigo (Indigofera tinctoria L.). Six isolates of Bradyrhizobium of indigo origin (HSTU-IR2, HSTU-IR3, HSTU-IR4, HSTU-IR9, HSTU-IR10 and HSTU-IR14) were collected from the

Journal of the Faculty of Agriculture, Kyushu University

Pakistan Journal of Biological Sciences, 2001

during the Aman season of 1999 to evaluate the effect of manures and fertilizers on the growth an... more during the Aman season of 1999 to evaluate the effect of manures and fertilizers on the growth and yield of BRRI Dhan 30. The experiment was laid out in Randomized Complete Block Design with three replications. There were seven treatments such as T 0 (control), T 1 (N 100), T 2 (N 100 S 10 Zn 5), T 3 (PM 5), T 4 (PM 7.5), T 5 (PM 10) and T 6 (CD 10). The results demonstrated that all the treatments had positive effect on the yield components and yields of BRRI Dhan 30. Grain and straw yields of BRRI Dhan 30 were significantly increased due to different treatment and the highest value was recorded with the application of poultry manure at 10 t haG 1. The NPKS content in BRRI Dhan 30 and their uptake were increased due to the application of manures and fertilizers. Analysis of post-harvest soils revealed that organic manure application had a positive influence on organic matter, total N, available P, exchangeable K, available S and CEC of the post-harvest soils.

Exposure and Health

In Bangladesh most agronomic biomass (straw, husk, dried dung) is burnt for domestic cooking use.... more In Bangladesh most agronomic biomass (straw, husk, dried dung) is burnt for domestic cooking use. Consequently, the soil is continuously stripped of mineral nutrients and carbon (C) substrate. Here we investigate if recycling of household ash (ash) as fertilizer can sustainably improve soil fertility as well as minimise accumulation of toxic elements (As, Cd) in rice grain. Large scale field trials across two geographic regions (Barind, Madhupur) and two seasons (wet, dry) and with application of 3 fertiliser treatments (NPKS, ash, NPKS + ash) were conducted. At the end of each season, the impact of region*season*treatment on soil microbial comunities, rice yield, and grain quality (As, Cd, nutrient elements) was assessed. When compared to conventional field application rates of NPKS (control), application of ash boosted rice yield by circa. 20% in both regions during wet and dry season, with no effect on rice grain carcinogenic inorganic arsenic (iAs), dimethylarsonic acid (DMA) or...

European Journal of Agriculture and Food Sciences

Reducing methane (CH4) emissions and water use in irrigated rice systems while maintaining produc... more Reducing methane (CH4) emissions and water use in irrigated rice systems while maintaining production to feed the ever-increasing population is vital in Bangladesh. Different rice establishment methods viz. alternate wetting & drying (AWD), system rice intensification (SRI) and direct wet seeded rice (DWSR), have a promising mitigation potential to reduce CH4emission compared to continuous flooded (CF) rice fields. A field experiment was conducted at Bangladesh Agricultural University, Mymensingh, during the Boro season in 2018 to examine whether rice establishment methods could maintain grain yield with reduced water use and CH4emissions. A split-plot design was employed with water management in the main plots and fertilizer management in the subplots. The yield difference was not significant (p>0.05) in CF, AWD, and SRI systems other than DWSR. Planting methods in combination with organic fertilizer amendment had little effect on the grain Fe, Zn, and Cd concentration but signi...

Exposure and Health

Despite the centrality of staple grains for human well-being, both as a source of nutrients and o... more Despite the centrality of staple grains for human well-being, both as a source of nutrients and of toxic ions, there is little understanding of where and how elements vary, and if there are particular elements that correlate. Here, for shop bought polished (white) rice, we comprehensively characterized trace (arsenic species, cadmium, copper, iron, manganese, molybdenum, rubidium and zinc) and macro-nutrients (calcium, chlorine, potassium, phosphorus and sulphur) for grain purchased in 18 countries, across four continents, a total of 1045 samples. This was to investigate if there were any major differences between geographic location and elemental content, and to observe if there were any patterns in elemental distribution. Greatest variation in the median was observed for the non-essential rubidium (15-fold) and arsenic species (fivefold). Rubidium was the highest in the Americas, lowest in Europe, while inorganic arsenic (iAs) and dimethylarsonic acid (DMA) were low for Africa and...

Land, 2021

Minimum soil disturbance and increased crop residue retention practices are promising options to ... more Minimum soil disturbance and increased crop residue retention practices are promising options to enhance soil organic matter, nutrient concentration and crop yield. However, the potentials of the practices in improving soil properties, increasing crop yield and in ensuring economic return have not been tested in the monsoon rice (Oryza sativa L.)-lentil (Lens culinaris L.)/wheat (Triticum aestivum L.)-jute (Corchorus culinaris L.) cropping systems on seasonally flooded lowlands of the Eastern Gangetic Plain of South Asia. A field trial for consecutive three years was conducted in the Gangetic Plains of Bangladesh to evaluate the effects of zero tillage (ZT), strip-tillage (ST), bed planting (BP) and conventional tillage (CT) with two residue retention levels (RL—a low level similar to current farmers’ practice and RH—increased retention) on soil properties, yield and economic return. Between rice and jute crops, lentil was grown for the 1st and 2nd years and wheat for the 3rd year d...

Despite the centrality of staple grains for human well-being, both as a source of nutrients and o... more Despite the centrality of staple grains for human well-being, both as a source of nutrients and of toxic ions, there is little understanding of where and how elements vary, and if there are particular elements that correlate. Here, for shop bought polished (white) rice we comprehensively characterize trace (arsenic species, cadmium, copper, iron, manganese, molybdenum, rubidium and zinc) and macro-nutrients (calcium, chlorine, potassium, phosphorus and sulphur) for grain purchased in 18 countries, across 4 continents, a total of 1045 samples, to investigate if there were any major differences between geographic location and elemental content, and to observe if there were any patterns in elemental distribution. Greatest variation in the median was observed for the non-essential rubidium (15-fold) and arsenic species (5-fold). Rubidium was highest in the Americas, lowest in Europe, while inorganic arsenic and dimethylarsonic acid (DMA) were low for Africa and high in the South America...

European Journal of Agriculture and Food Sciences, 2021

Zinc (Zn) deficiency is widespread nutrient disorder in lowland rice growing areas in Asia, espec... more Zinc (Zn) deficiency is widespread nutrient disorder in lowland rice growing areas in Asia, especially in Bangladesh. Intensive cropping with modern varieties causes depletion of inherent nutrient reserves in soils. The application of Zn fertilizers results in higher crop productivity and increases Zn concentration in crops. A field experiment was conducted to evaluate the effect of Zn application on growth, yield, and grain-Zn concentration in eight varieties of rice. The experiment was laid out in a split plot design with a distribution of Zn rates (0 kg ha-1 and 3 kg ha-1 from ZnO) to the main plots and rice varieties (BRRI dhan49, BRRI dhan52, BRRI dhan56, BRRI dhan57, Kalizira, Biroin, Gainja and Khirshapath) to the sub-plots. Zinc application improved effective tillers hill-1, grains panicle-1 and 1000-grain weight which impacted the grain yield of rice. Among the eight rice varieties, a significant increase of grain yield was recorded in BRRI dhan49, BRRI dhan52, BRRI dhan56 ...

Exposure and Health, 2020

One of cadmium’s major exposure routes to humans is through rice consumption. The concentrations ... more One of cadmium’s major exposure routes to humans is through rice consumption. The concentrations of cadmium in the global polished (white), market rice supply-chain were assessed in 2270 samples, purchased from retailers across 32 countries, encompassing 6 continents. It was found on a global basis that East Africa had the lowest cadmium with a median for both Malawi and Tanzania at 4.9 μg/kg, an order of magnitude lower than the highest country, China with a median at 69.3 μg/kg. The Americas were typically low in cadmium, but the Indian sub-continent was universally elevated. In particular certain regions of Bangladesh had high cadmium, that when combined with the high daily consumption rate of rice of that country, leads to high cadmium exposures. Concentrations of cadmium were compared to the European Standard for polished rice of 200 μg/kg and 5% of the global supply-chain exceeded this threshold. For the stricter standard of 40 μg/kg for processed infant foods, for which rice ...

Environmental Science & Technology, 2019

Fundamental and Applied Agriculture, 2018

Journal of the Bangladesh Agricultural University, 2010

A study was made on the effect of arsenic (As) and As X P interaction in Boro rice and its residu... more A study was made on the effect of arsenic (As) and As X P interaction in Boro rice and its residual effect in succeeding T. Aman rice. Arsenic was added to soil (having 2.6 ppm initial As) @ 0, 15 and 30 mg As kg -1 from Na2HAsO4.7H2O and phosphorus @ 0, 20, 40, 60 and 80 mg P kg-1 from KH2PO4. Each pot had received 100 ppm N, 40 ppm K and 25 ppm S from urea, MoP and gypsum, respectively. The grain yield of Boro rice was reduced by 20.6 % for 15 ppm As treatment and 63.8 % due to 30 ppm As. Such reductions for straw yield were 21.0 and 65.2 % with these two As treatments, respectively. Residual effect of arsenic was also significant and negative in T. Aman rice. The grain-As concentration in all cases was below 1 ppm, and the straw-As content was well above 1 ppm. The arsenic concentrations of both grain and straw were lower in T. Aman rice than in Boro rice. The adverse effect of arsenic was further enhanced by P addition. This reaction has an implication to P fertilizer management...

New Phytologist, 2011

• Inorganic arsenic (As i) in rice (Oryza sativa) grains is a possible threat to human health, wi... more • Inorganic arsenic (As i) in rice (Oryza sativa) grains is a possible threat to human health, with risk being strongly linked to total dietary rice consumption and consumed rice As i content. This study aimed to identify the range and stability of genetic variation in grain arsenic (As) in rice. • Six field trials were conducted (one each in Bangladesh and China, two in Arkansas, USA over 2 yr, and two in Texas, USA comparing flooded and nonflood treatments) on a large number of common rice cultivars (c. 300) representing genetic diversity among international rice cultivars. • Within each field there was a 3-34 fold range in grain As concentration which varied between rice subpopulations. Importantly, As i correlated strongly with total As among a subset of 40 cultivars harvested in Bangladesh and China. • Genetic variation at all field sites was a large determining factor for grain As concentration, indicating that cultivars low in grain As could be developed through breeding. The temperate japonicas exhibited lower grain As compared with other subpopulations. Effects for year, location and flooding management were also statistically significant, suggesting that breeding strategies must take into account environmental factors.

Environmental Science & Technology, 2009

An extensive data set of total arsenic analysis for 901 polished (white) grain samples, originati... more An extensive data set of total arsenic analysis for 901 polished (white) grain samples, originating from 10 countries from 4 continents, was compiled. The samples represented the baseline (i.e., not specifically collected from arsenic contaminated areas), and all were for market sale in major conurbations. Median total arsenic contents of rice varied 7-fold, with Egypt (0.04 mg/kg) and India (0.07 mg/kg) having the lowest arsenic content while the U.S. (0.25 mg/kg) and France (0.28 mg/kg) had the highest content. Global distribution of total arsenic in rice was modeled by weighting each country's arsenic distribution by that country's contribution to global production. A subset of 63 samples from Bangladesh, China, India, Italy, and the U.S. was analyzed for arsenic species. The relationship between inorganic arsenic content versus total arsenic content significantly differed among countries, with Bangladesh and India having the steepest slope in linear regression, and the U.S. having the shallowest slope. Using country-specific rice consumption data, daily intake of inorganic arsenic was estimated and the associated internal cancer risk was calculated using the U.S. Environmental Protection Agency (EPA) cancer slope. Median excess internal cancer risks posed by inorganic arsenic ranged 30-fold for the 5 countries examined, being 0.7 per 10,000 for Italians to 22 per 10,000 for Bangladeshis, when a 60 kg person was considered.

Environmental Science & Technology, 2008

Rice is more elevated in arsenic than all other grain crops tested to date, with whole grain (bro... more Rice is more elevated in arsenic than all other grain crops tested to date, with whole grain (brown) rice having higher arsenic levels than polished (white). It is reported here that rice bran, both commercially purchased and specifically milled for this study, have levels of inorganic arsenic, a nonthreshold, class 1 carcinogen, reaching concentrations of ∼1 mg/kg dry weight, around 10-20 fold higher than concentrations found in bulk grain. Although pure rice bran is used as a health food supplement, perhaps of more concern is rice bran solubles, which are marketed as a superfood and as a supplement to malnourished children in international aid programs. Five rice bran solubles products were tested, sourced from the United States and Japan, and were found to have 0.61-1.9 mg/kg inorganic arsenic. Manufactures recommend ∼20 g servings of the rice bran solubles per day, which equates to a 0.012-0.038 mg intake of inorganic arsenic. There are no maximum concentration levels (MCLs) set for arsenic or its species in food stuffs. EU and U.S. water regulations, set at 0.01 mg/L total or inorganic arsenic, respectively, are based on the assumption that 1 L of water per day is consumed, i.e., 0.01 mg of arsenic/ day. At the manufacturers recommended rice bran solubles consumption rate, inorganic arsenic intake exceeds 0.01 mg/ day, remembering that rice bran solubles are targeted at malnourished children and that actual risk is based on mg kg-1 day-1 intake.