82 research outputs found

    Effects of mulching on growth and yield components of selected varieties of wheat (Triticum aestivum L.) under field condition

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    Wheat is facing increased high temperature during its grain filling period in Bangladesh which reduces yield drastically. Mulching may help to mitigate this problem. Therefore, a field experiment was carried out at the Agronomy Field Laboratory, Bangladesh Agricultural University, Mymensingh during the period from November 2015 to March 2016 to find out growth and yield performance of wheat as influenced by mulching. The experiment comprised of two factors viz., variety and mulching. The variety comprised of BARI Gom-26, BARI Gom-27 and BARI Gom-28. Mulching comprised of four different levels of treatments viz.no mulch + no irrigation (control), water hyacinth mulch + no irrigation, rice straw mulch + no irrigation and two irrigations at CRI and flowering stage. The experiment was laid out in a randomized complete block design with three replications. BARI Gom-28 showed the highest values in growth parameters (plant height, number of total tillers hill-1, LAI, chlorophyll content and total dry matter) at 30, 45 and 60 DAS. On the other hand, when mulching was compared, rice straw mulch gave higher yield compared to other treatments at 30, 45 and 60 DAS. The interaction effect of variety and mulching showed significant in relation to yield and yield components except plant height, spike length, 1000- grain weight and harvest index (%). The tallest plant (93.20 cm) was obtained from the interaction of BARI Gom-28 and rice straw mulch. The highest number of total tillers hill-1 (4.80), number of effective tillers hill-1 (4.57), spike length (10.23), number of spikelets spike-1 (21.15), 1000-grain weight (48.54 g), grain yield (5.20 t ha-1), straw yield (7.27 t ha-1), and harvest index (41.71%) were obtained from the interaction of BARI Gom-28 and rice straw mulch. The lowest grain yield was obtained from BARI Gom-26 and control (no mulch + no irrigation). It may be concluded from the results of the study that, BARI Gom-28 with rice straw mulching treatment can be used for successful cultivation of wheat

    Physiological parameters and yield differ in rice (Oryza sativa L.) cultivars with variable water management systems

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    Yield reduction of rice is a severe problem due to the advent of increasing water scarcity and efficiency is relatively low. Physiological attributes and yield performance of high yielding (HYV) rice cultivars need to be assessed by minimizing water loss. Therefore, a glasshouse experiment was conducted in Bangladesh to investigate the impact of cultivars and water management on growth dynamics, biomass production, and yield and water productivity. Ten HYV boro (dry season irrigated) rice cultivars along with fivewater management systems were included in the study. The study revealed that cultivars Binadhan-10 had higher value of leaf area index (LAI), root dry weight along with moderate panicle length. Accordingly, the cultivar Binadhan-10 had a higher yield than all other cultivars because of the highest total dry matter (TDM), number of effective tillers hill-1, and number of grains panicle-1. Growth, TDM, and yield were increased with water application up to 8 DAD after which these factors declined with increasing water stress at 10 DAD. The crop grown at CS condition did not increase the yield, rather caused the wastage of irrigation water. The water productivity was the highest (0.252 t ha-1cm-1) in 10 DAD treatments, obviously due to minimum water use but highest yield was observed in 8 DAD because of optimum use of water and non stress condition. Therefore, the present study was useful in the screening of the most efficient cultivars, which could be strongly recommended to rice growers to improve crop yield and reduce the use of water

    Effects of bio-slurry with chemical fertilizer on the performance of some high yielding varieties of boro rice (Oryza sativa L.)

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    Rice yield is greatly influenced by application of manures and fertilizer. Integrated use of organic manure and chemical fertilizer would be quite promising in providing better yield. To evaluate the effect of bio-slurry along with chemical fertilizer, a field experiment was conducted in the Agronomy Field Laboratory, Bangladesh Agricultural University, Mymensingh, Bangladesh. The experiment was comprised of four varieties of boro (dry season irrigated) rice viz., (i) BRRI dhan28, (ii) BRRI dhan29 (iii) Binadhan-8 (iv) Binadhan-10 and four fertilizer management viz., (i) control, (ii) recommended dose of inorganic fertilizer, (iii) bio-slurry@ 5 t ha-1 + inorganic fertilizer, (iv) farmers’ practice (average 15 farmers). The experiment was laid out in a randomized complete block design with three replications. It is evident that variety and fertilizer management had significant effect on effective tillers hill-1, number of grains panicle-1 which ultimately influenced grain yield. The highest grain yield was (6.03 t ha-1) in Binadhan-8 followed by Binadhan-10 and BRRI dhan29. The lowest grain yield was found from BRRI dhan28. In respect of fertilizer management, grain yield was highest (5.90 t ha-1) in bio-slurry @ 5 t/ha + inorganic fertilizer. The lowest grain yield was found from control. The combined effect of variety and fertilizer application showed that highest grain yield (6.10 t ha-1) was found from Binadhan-8 with bio-slurry @ 5 t ha-1 + inorganic fertilizer and the lowest grain yield (4.68 t ha-1) was found from BRRI dhan28 with farmers’ practice. Thus, the variety Binadhan-8 with application of bio-slurry @ 5 t ha-1 + inorganic fertilizer was superior for obtaining highest yield

    Type 2 diabetes and its correlates among adults in Bangladesh: a population based stud

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    Type 2 diabetes is one of the most prevalent non-communicable diseases in Bangladesh. However, the correlates of type 2 diabetes among adults in Bangladesh remain unknown. We aimed to investigate the correlates of type 2 diabetes among the adults in Bangladesh. Methods : We conducted a cross-sectional study using data from the nationally representative 2011 Bangladesh Demographic and Health Survey. A random sample of 7,543 (3,823 women and 3,720 men) adults of age 35 years and older from both urban and rural areas, who participated in the survey was included. Diabetes was defined as having a fasting plasma blood glucose level of ≥ 7 mm/L or taking diabetes medication during the survey. Hypothesized factors, e.g., age, sex, education, place of residence, social status, body mass index, and hypertension were considered in the analyses. Multivariable logistic regression models were used to identify the important correlates of type 2 diabetes. Results : Among the respondents, the overall prevalence of diabetes was 11 %, and the prevalence was slightly higher in women (11.2 %) than men (10.6 %). Respondents with the age group of 55–59 years had higher odds of having diabetes (odds ratios (OR) = 2.37, 95 % confidence interval (CI): 1.76–3.21) than the age group of 35–39 years. Moreover, respondents who had higher educational attainment (OR = 1.67, 95 % CI: 1.18–2.36) and higher social status (OR = 2.01, 95 % CI: 1.50–2.70) had higher odds of having diabetes than the respondents with no education and lower social status, respectively. We also found socioeconomic status, place of residence (rural or urban), regions of residence (different divisions), overweight and obesity, and hypertension as significant correlates of type 2 diabetes in Bangladesh. Conclusions: Our study shows that older age, higher socioeconomic status, higher educational attainment, hypertension, and obesity were found to be significant correlates of type 2 diabetes. Need-based policy program strategies including early diagnosis, awareness via mass media, and health education programs for changing lifestyles should be initiated for older age, wealthy, and/or higher educated individuals in Bangladesh. Moreover, area-specific longitudinal research is necessary to find out the underlying causes of regional variations

    Engineering provitamin A synthesis pathway with β-carotene metabolism in rice endosperm of a restorer line BR827R

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    Vitamin A deficiency (VAD) is a serious public health problem in South Asia particularly in Bangladesh. Indica rice as a major staple in the country completely lacks vitamin A or compounds with provitamin A activity after milling. A combination of transgenes has been introduced enabling biosynthesis of provitamin A in the endosperm of a restorer line using biolistic system of transformation. The rice seed-specific glutelin promoter (Gt-1 P) was used to drive the expression of phytone synthase (psy), while lycopene b-cyclase (lcy) and phytoenedesaturase (crtI), fused to the transit peptide sequence of the pea-Rubisco small subunit, were driven by the constitutive cauliflower mosaic virus promoter (CaMV35s P). Transgenic plants were recovered through selection with CaMV35sP driven hph (hygromycinphosphotransferase) gene. Molecular analysis demonstrated stable integration and expression of the transgenes. The variable segregation pattern in T1 generation indicated single to multiple insertions of the transgenes in the genome. This is the first report of the development of a transgenic restorer line with carotenogenic pathway into the endosperm for use of hybrid rice improvement

    Modelling and simulation of 1.2 MWp tenaga suria brunei photovoltaic power plant

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    The energy demand in Brunei Darussalam will increase in near future. The renewable energy is one of the alternative energy sources that could satisfy the increasing energy demands. Brunei Darussalam depends heavily on fossil fuel to generate its electricity needs. Fossil fuels are depleted and the main source of pollution. Photovoltaic (PV) systems generate electricity directly from the sunlight without any emission of global warming gases, and the fuel is free. In order to optimize the performance of PV systems their operation should be well understood. In this paper, we present the modelling of a real 1.2 MWp photovoltaic system. The PV power plant is tied to the grid. The PV array, the DC/DC converter and the DC/AC inverter are modelled and implemented in Matlab/Simulink. The controller of the gridconnected inverter is modelled to achieve constant voltage, constant frequency and to be synchronized with the grid. The system is simulated under Brunei weather conditions and the results are acceptable

    Technical and economic feasibility study of solar powered air conditioners in Brunei Darussalam

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    On daily basis, a huge amount of fossil fuel is being burnt which results in a substantial amount of greenhouse gasses being released into the atmosphere. Air conditioners are becoming more common and are a major strain on energy demands especially in tropical climate countries like Brunei Darussalam. The photovoltaic electricity is a clean and sustainable. In this paper, we present a techno-economic feasibility study for solar powered air conditioning system in Brunei Darussalam. Four alternatives are investigated, 1) the PV system supplies 50% of the loads, 2) the PV system supplies 75% of the loads, 3) the PV system supplies 100% of the loads, and finally 4) the PV system supplies 125% of the loads. Where in the last two case the excess electricity is sold to the grid. With 0.3$ feed-in tariff. The best alternative is the grid-connected PV system with 125% capacity factor which was chosen due to its short payback time period as well as high profit rate over the lifetime of the project

    Homologous Flares and Magnetic Field Topology in Active Region NOAA 10501 on 20 November 2003

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    We present and interpret observations of two morphologically homologous flares that occurred in active region (AR) NOAA 10501 on 20 November 2003. Both flares displayed four homologous H-alpha ribbons and were both accompanied by coronal mass ejections (CMEs). The central flare ribbons were located at the site of an emerging bipole in the center of the active region. The negative polarity of this bipole fragmented in two main pieces, one rotating around the positive polarity by ~ 110 deg within 32 hours. We model the coronal magnetic field and compute its topology, using as boundary condition the magnetogram closest in time to each flare. In particular, we calculate the location of quasiseparatrix layers (QSLs) in order to understand the connectivity between the flare ribbons. Though several polarities were present in AR 10501, the global magnetic field topology corresponds to a quadrupolar magnetic field distribution without magnetic null points. For both flares, the photospheric traces of QSLs are similar and match well the locations of the four H-alpha ribbons. This globally unchanged topology and the continuous shearing by the rotating bipole are two key factors responsible for the flare homology. However, our analyses also indicate that different magnetic connectivity domains of the quadrupolar configuration become unstable during each flare, so that magnetic reconnection proceeds differently in both events.Comment: 24 pages, 10 figures, Solar Physics (accepted
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