Dongming G.,Beijing Technology and Business University |
Lianhao L.,Henan Agricultural University |
Sarker K.K.,Bangladesh Agricultural Research Institute BARI
International Journal of Agricultural and Biological Engineering | Year: 2017
In order to fully understand the relationships of power consumption of no-till planter among tractor, soil properties and working parameters which affect the field operation, the power consumption model for no-till planter applied to overcome the coupling difficulties was developed in the study. Based on operation depth of no-till planter and soil properties as constraints in accordance with a certain distribution, we collected and analyzed the relationship data among traction force, forward speed and power output shaft by field test. The results showed that the relationship between traction power and power-take-off (PTO) power was negatively correlated. Under the same power consumption condition, the relationship between traction force and the PTO torque was linearly correlated, and the slope was basically consistent. Different power consumptions corresponded to different intercepts. When the forward speed was 6-7 km/h and PTO shaft rotational speed was 370-450 r/min, lower power consumption with higher working efficiency can be achieved. There was a direct correlation between total power consumption and the square of rotational speed multiplied by forward speed. The maximum correlation coefficient was found around 0.82. The findings set up a foundation for designing control system of no-till planter. © 2017, Chinese Society of Agricultural Engineering. All rights reserved.
Hossain M.A.,Bangladesh Agricultural Research Institute BARI |
Sarker A.K.,WorldFish |
Amin M.N.,Bangladesh Agricultural Research Institute BARI |
Hossain M.M.,Bangladesh Agricultural Research Institute BARI |
Miah M.S.,Bangladesh Agricultural Research Institute BARI
Aquacultural Engineering | Year: 2016
Fishery is an emerging sector in Bangladesh producing about 3.50 million tons of fish annually of which aquaculture accounts for 2.00 million tons. In intensive aquaculture, pond water gets polluted due to high stocking density and large amount of supplemental feeding results in huge accumulation of unused feed and faeces in the pond bottom. The accumulated bottom sludge depletes dissolved oxygen (DO) and releases harmful gases due to excessive use of chemicals and lack of water exchange facilities. These have negative impact on fish production and economic performance, through disease outbreak, mortality, poor feed conversion ratio (FCR), specific growth rate (SGR) and bad odor in fish muscles. This study was undertaken to develop a sludge remover for cleaning sludge from the intensive fish farming pond and to find the impact of sludge removal on water quality and growth of fish. A sludge remover was developed in Bangladesh Agricultural Research Institute (BARI) which is capable of removing sludge up to 40-50 mm from the pond bottom. The main components of sludge remover are a float, axial flow pump (102 mm diameter), 7.50 kW diesel engine, sludge sucker, crane, propeller, rudder, etc. The discharge of the sludge pump was 14.11 L/s. The effective field capacity and field efficiency were 0.078 ha/h and 77.23% respectively at the forward speed of 12.5 ± 1.55 m/min. The water and sludge ratio was 3.6:1.0 (weight basis). A field trial was carried out to determine the effect of sludge removal on water quality and growth of fishes in intensive cultured ponds. Sludge was removed at three months interval from three pangus-tilapia-carp polyculture ponds. Three ponds of same size and fish stocking were kept as control. Water quality parameters like DO, pH, transparency and, unionized ammonia significantly (p ≤ 0.05) improved in the sludge removed ponds compare to control ponds. Sludge removed ponds demonstrated better FCR (1.64) and SGR (0.80% per day) compare to FCR (1.90) and SGR (0.71% per day) of control ponds. Fish survival, net yield, net return and BCR (5.40) of sludge removed ponds were higher than those of control ponds. This sludge remover may be recommended for cleaning sludge from intensive cultured fish ponds. © 2016 Elsevier B.V.
Zhang H.,Chinese Academy of Agricultural Sciences |
Uddin M.S.,Chinese Academy of Agricultural Sciences |
Uddin M.S.,Bangladesh Agricultural Research Institute BARI |
Zou C.,Chinese Academy of Agricultural Sciences |
And 4 more authors.
Journal of Integrative Plant Biology | Year: 2014
Plants with tolerance to low-phosphorus (P) can grow better under low-P conditions, and understanding of genetic mechanisms of low-P tolerance can not only facilitate identifying relevant genes but also help to develop low-P tolerant cultivars. QTL meta-analysis was conducted after a comprehensive review of the reports on QTL mapping for low-P tolerance-related traits in maize. Meta-analysis produced 23 consensus QTL (cQTL), 17 of which located in similar chromosome regions to those previously reported to influence root traits. Meanwhile, candidate gene mining yielded 215 genes, 22 of which located in the cQTL regions. These 22 genes are homologous to 14 functionally characterized genes that were found to participate in plant low-P tolerance, including genes encoding miR399s, Pi transporters and purple acid phosphatases. Four cQTL loci (cQTL2-1, cQTL5-3, cQTL6-2, and cQTL10-2) may play important roles for low-P tolerance because each contains more original QTL and has better consistency across previous reports. © 2014 Institute of Botany, Chinese Academy of Sciences.
Schreinemachers P.,The World Vegetable Center |
Wu M.-H.,The World Vegetable Center |
Uddin M.N.,Grameen Foundation |
Ahmad S.,Bangladesh Agricultural Research Institute BARI |
Hanson P.,The World Vegetable Center
Food Policy | Year: 2016
The cultivation of crops outside the regular cropping calendar when supply is low and prices are high can give farmers better profits and consumers more choice. However, off-season production may increase pesticide risk if crops are more affected by pests and diseases and farmers do not handle pesticides correctly. This study quantified the effect of training in off-season tomato production on the income and pesticide use of smallholder vegetable farmers in southwestern Bangladesh. The study uses farm-level data from 94 trained and 151 non-trained farm households and applies propensity score matching and inverse probability weighting to correct for selection bias. For the average smallholder vegetable farmer, training increased net household income by about 48%. We found that 31% of the trained farm households who had initially adopted the technology continued its use in the second year, but farm households who discontinued using the technology also experienced significant income gains from the training. There was a significant increase in pesticide use (+56%) and although there was an improvement in pesticide handling practices, trained farmers may have been more exposed to pesticide health risk. The policy implication is that while off-season vegetable production can create dramatic income improvements, it is important to emphasize safe and sustainable pest management methods as part of policies promoting it. © 2016 The Authors.
Latif M.A.,University Putra Malaysia |
Latif M.A.,Bangladesh Rice Research Institute BRRI |
Rahman M.M.,Bangladesh Agricultural Research Institute BARI |
Ali M.E.,University of Malaya |
And 2 more authors.
Comptes Rendus - Biologies | Year: 2013
Multivariate analyses were performed using 13 morphological traits and 13 molecular markers (10 SSRs and three ISSRs) to assess the phylogenetic relationship among tungro resistant genotypes. For morphological traits, the genotypes were grouped into six clusters, according to D2 statistic and Canonical vector analysis. Plant height, days to flowering, days to maturity, panicle length, number of spikelet per panicle, number of unfilled grain per panicle and yield were important contributors to genetic divergence in 14 rice genotypes. Based on Nei's genetic distance for molecular studies, seven clusters were formed among the tungro resistant and susceptible genotypes. Mantel's test revealed a significant correlation (r = 0.834*) between the morphological and molecular data. To develop high yielding tungro resistant varieties based on both morphological and molecular analyses, crosses could be made with susceptible (BR10 and BR11) genotypes with low yielding but highly resistant genotypes, Sonahidemota, Kumragoir, Nakuchimota, Khaiyamota, Khairymota and Kachamota. The chi-square analysis for seven alleles (RM11, RM17, RM20, RM23, RM80, RM108 and RM531) of SSR and five loci (RY1, MR1, MR2, MR4 and GF5) of three ISSR markers in F2 population of cross, BR11 × Sonahidemota, showed a good fit to the expected segregation ratio (1:2:1) for a single gene model. © 2013 Académie des sciences.
Rahman S.,University of Plymouth |
Hasan M.K.,Bangladesh Agricultural Research Institute BARI
Energy | Year: 2014
Wheat is the second most important cereal crop in Bangladesh and production is highly sensitive to variations in the environment. We estimate productivity and energy efficiency of wheat farming in Bangladesh by applying a stochastic production frontier approach while accounting for the environmental constraints affecting production. Wheat farming is energy efficient with a net energy balance of 20,596MJ per ha and energy ratio of 2.34. Environmental constraints such as a combination of unsuitable land, weed and pest attack, bad weather, planting delay and infertile soils significantly reduce wheat production and its energy efficiency. Environmental constraints account for a mean energy efficiency of 3 percentage points. Mean technical efficiency is 88% thereby indicating that elimination of inefficiencies can increase wheat energy output by 12%. Farmers' education, access to agricultural information and training in wheat production significantly improves efficiency, whereas events such as a delay in planting and first fertilization significantly reduce it. Policy recommendations include development of varieties that are resistant to environmental constraints and suitable for marginal areas; improvement of wheat farming practices; and investments in education and training of farmers as well as dissemination of information. © 2014 Elsevier Ltd.
Matin M.A.,University of South Australia |
Matin M.A.,Bangladesh Agricultural Research Institute BARI |
Fielke J.M.,University of South Australia |
Desbiolles J.M.A.,University of South Australia
Biosystems Engineering | Year: 2014
Two-wheeled tractors fitted with rotary cultivators are used in many developing countries for full disturbance soil tillage. Recent development, motivated by the benefits of conservation agriculture, is working toward strip-tillage seeding using two-wheeled tractors fitted with modified rotary cultivators and seeding attachments. The effect of three blade geometries (conventional, half-width and straight) at four rotary speeds (125, 250, 375, and 500rpm) on the furrow seedbed parameters when used for strip-tillage was investigated. The experimental blades were mounted on a rotary tiller test unit operating in a reconstituted sandy loam soil travelling at a forward speed of 0.67ms-1. Analysis of the high-speed video showed that the straight blade reduced the soil carrying and throwing. At 125rpm all blades produced either an unsatisfactory cloddy seedbed with an irregular furrow bottom and walls or an incomplete furrow. At 500rpm, considerable amounts of soil were thrown out of the furrow for the conventional and half-width blades which achieved furrow backfills of only 41 and 36%, respectively. The straight blade achieved the fullest backfill at 74% even when operating at 500rpm. The level of soil pulverisation increased with rotary speed, but was not affected by blade geometry. Each of the blades produced different furrow shapes with a higher furrow volume tilled by the conventional and the straight blades compared to that by the half-width blades. Based on its high backfill and large furrow volume, the straight blade would be the preferred option when undertaking rotary strip-tillage. © 2013.
Rahman S.,University of Plymouth |
Rahman M.S.,Bangladesh Agricultural Research Institute BARI
Energy | Year: 2013
The paper evaluates sustainability of maize cultivation in Bangladesh in terms of energy use while taking into account factors affecting choice of the growing season and farmers' production environment using a sample selection framework applied to stochastic frontier models. Results reveal that the probability of growing winter maize is influenced positively by gross return, irrigation, subsistence pressure, soil suitability and temperature variability whereas extension contact influences choice negatively. Significant differences exist between winter and summer maize regarding yield, specific energy, net energy balance, energy use efficiency and technical energy efficiency although both systems are highly sustainable and efficient. The energy output from winter maize is 199,585 MJ/ha which is 53.9% higher than the summer maize output of 129,701 MJ/ha. Also, energy input use of winter maize is 110.6% higher than the summer maize. Energy inputs from mechanical power, seeds, fertilizers and organic manures significantly increase energy productivity of winter maize whereas only mechanical power influences summer maize productivity. However, temperature variation and rainfall significantly reduce energy productivity of summer maize. Policy implications include investments in soil conservation and irrigation, development of weather resistant varieties and raising maize price will boost maize cultivation in Bangladesh, a highly sustainable production technology. © 2012 Elsevier Ltd.
Malaker P.K.,Bangladesh Agricultural Research Institute BARI |
Reza M.M.A.,Bangladesh Agricultural Research Institute BARI
Czech Journal of Genetics and Plant Breeding | Year: 2011
Leaf rust caused by Puccinia triticina is the most important disease among the three rusts of wheat in Bangladesh. The disease occurs in all wheat growing areas of the country with varying degrees of severity. Stem rust caused by P. graminis f.sp. tritici was last observed during the mid 1980s, while yellow rust caused by P. striiformis f.sp. tritici occurs occasionally in the north-western region, where a relatively cooler climate prevails during the winter months. None of the rusts has yet reached an epidemic level, but damaging epidemics may occur in future, particularly if a virulent race develops or is introduced. The genes conferring rust resistance in the breeding lines and wheat varieties released in Bangladesh were investigated at CIMMYT-Mexico and DWR-India. The resistance genes Lr1, Lr3, Lr10, Lr13, Lr23 and Lr26, Sr2, Sr5, Sr7b, Sr8b, Sr9b, Sr11 and Sr31; and Yr2KS and Yr9 were found. An adult plant slow rusting resistance gene Lr34 was also identified in some of the breeding lines and varieties based on the presence of clear leaf tip necrosis under field conditions. Considering the possible risk of migration of the devastating Ug99 race of stem rust into the Indo-Pak subcontinent, the Bangladeshi wheat lines and cultivars are being regularly sent to KARI in Kenya for testing their resistance against this race. The resistant lines have been included in multi-location yield trials and multiplied for future use in order to mitigate the threat of Ug99. The resistant lines have also been included in crossing schemes to develop genetic diversity of rust resistance.
Rahman M.M.,Bangladesh Agricultural University |
Ahammad K.U.,Bangladesh Agricultural Research Institute BARI |
Alam M.M.,Bangladesh Agricultural Research Institute BARI
Research Journal of Seed Science | Year: 2011
This study was conducted to determine the effect of priming temperature and soaking condition on water absorption pattern of maize (variety BARI hybrid maize-5) and chickpea (BARI chola-5) seeds. Two soaking conditions viz., (1) aerobic and (2) anaerobic and three priming temperature levels viz., (1) 15 (2) 25 and (3) 31°C (ambient) were used in the experiment. The experiment was laid out in a completely randomized design with three replications. BARI hybrid maize-5 and BARI chola-5 seeds absorbed water very rapidly for up to 6 h both in aerobic and anaerobic conditions at all the levels of temperatures. Thereafter a little change in absorption rate was found for up to 30 h in maize and 24 h in chickpea seeds while a slow increase was further notices for up to 70 h for both the seeds under all the environmental conditions with a little higher rate at aerobic environment than the anaerobic environment. It is observed that visible germination occurred in maize during 30 to 40 h and in chickpea during 24 to 30 h of imbibition. The present study revealed that imbibition period for both maize and chickpea seed increased with increasing temperature and the rate of water absorption was always higher in anaerobic condition than the aerobic condition. The present study concludes that optimum duration of soaking for maize and chickpea seeds at 31, 25 and 15°C of soaking temperature could be 6, 9 and 18 h, respectively. © 2011 Academic Journals Inc.