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101.
Lulu Rayhan Khushi SM Rubaiot Abdullah Sanjoy Saha Mohammad Raqibul Hasan Siddique 《Southern Forests》2019,81(1):45-48
Gmelina arborea Roxb. is a fast-growing, deciduous tree species native to Bangladesh. It has been widely planted since 1992 for commercial production of pulpwood in hilly areas of Bangladesh. The purpose of this study was to derive well-fitting allometric models for estimation of aboveground biomass, and carbon and nutrient (nitrogen, phosphorus and potassium) stocks in G. arborea to ensure sustainable production and management of this species. Eight linear models with 64 regression equations were tested for estimation of aboveground biomass, carbon and nutrient stocks in different parts (leaves, branches, bark and stem) of the plant. The best-fitting allometric models were selected in accordance with various relevant statistical criteria. 相似文献
102.
The antidiarrhoeal activity of the methanol extract of the dried seeds of Strychnos potatorum (MESP) has been evaluated out in rats using different models (castor oil-induced diarrhoea, effects on gastrointestinal motility and on PGE(2)-induced gastric enteropooling. MESP (100, 200 and 400 mg/kg, p.o.) significantly (P<0.001) inhibited the frequency of defaecation and reduced the wetness of faecal droppings in castor oil-induced diarrhoea, decreased the propulsion of charcoal meal through the gastrointestinal tract, and also reduced the PGE(2)-induced enteropooling. 相似文献
103.
The methanol extract of aerial parts of Barleria lupulina orally tested at doses of 100, 200 and 300 mg/kg exerted significant antihyperglycemic effect in streptozotocin-induced hyperglycemia in rats [correction]. 相似文献
104.
Subhrajit K. Saha P. K. Ramachandran Nair Vimala D. Nair B. Mohan Kumar 《Agroforestry Systems》2009,76(1):53-65
Conservation of biodiversity and mitigation of global warming are two major environmental challenges today. In this context,
the relationship between biodiversity (especially plant diversity) and soil carbon (C) sequestration (as a means of mitigating
global warming) has become a subject of considerable scientific interest. This relationship was tested for homegardens (HG),
a popular and sustainable agroforestry system in the tropics, in Thrissur district, Kerala, India. The major objectives were
to examine how tree density and plant-stand characteristics of homegardens affect soil C sequestration. Soil samples were
collected at four depths (0–20, 20–50, 50–80, 80–100 cm) from HG of varying sizes and age classes, and their total C content
determined. Tree density and plant-stand characteristics such as species richness (Margalef Index) and diversity (Shannon
Index) of the HG were also determined. Results indicated that the soil C stock was directly related to plant diversity of
HG. Homegardens with higher, compared to those with lower, number of plant species, as well as higher species richness and
tree density had higher soil carbon, especially in the top 50 cm of soil. Overall, within 1 m profile, soil C content ranged
from 101.5 to 127.4 Mg ha−1. Smaller-sized HG (<0.4 ha) that had higher tree density and plant-species density had more soil C per unit area (119.3 Mg ha−1) of land than larger-sized ones (>0.4 ha) (108.2 Mg ha−1). Soil C content, especially below 50 cm, was higher in older gardens. The enhanced soil-C storage in species-rich homegardens
could have relevance and applications in broader ecological contexts.
相似文献
Subhrajit K. SahaEmail: |
105.
Supradip Saha Gyanendra Singh V. Mahajan H. S. Gupta 《Plant foods for human nutrition (Dordrecht, Netherlands)》2009,64(2):174-180
Screening of natural biodiversity for the better quality traits are of prime importance for quality breeding programs. The
objective of this investigation was to select candidate accession of bean having high concentrations of protein as well as
macro and micro minerals with good cooking quality for use as parents in breeding programme for these compounds. Thirty-five
accessions of bean (Phaseolus vulgaris L) were field grown and their seeds were analyzed for their cooking quality and nutritional composition. Wide variations
were observed in most of the measurements e.g. protein (18.7–26.2%), iron (79.4–137.6 ppm) and hardness after cooking (4.65–9.88 Kg)
suggesting that there are considerable levels of genetic diversity. Across all accessions the concentration of potassium was
negatively correlated with protein (r = −0.43, P < 0.05). Concentrations of protein was significantly greater in accessions VIII, XIII and XIX compared to other accessions
analyzed. Iron concentrations were greatest (137 ppm) in XIX and lowest (79 ppm) in XXVII. Lines with less cooking time were
line III, X, XXVI, XXX and XXXI. Bean line XIX contains high protein (24.9%) with high zinc (33.3 ppm) and highest iron (137.6 ppm),
but it has high hardness after cooking (7.32 kg). Four clusters were computed by cluster analysis that explained quite a good
variation in the traits. The great variability for these attributes suggests that these selected accessions may be useful
as parents in hybridization programs to produce bean with value-added traits. This information was also potentially useful
for pulse breeders working on the development of new varieties. 相似文献
106.
Jayanta K. Saha Amar B. Singh A. N. Ganeshamurthy Samaresh Kundu Ashish K. Biswas 《植物养料与土壤学杂志》2001,164(3):317-320
Application of S through inorganic sources is recommended to the crops in the cropping system in S deficient soils of India. However, transformations of S in the soil profile following continuous gypsum application are not known. The accumulation of S into different fractions due to application of a total of 180—540 kg S ha—1 over a six‐year‐period in soybean — wheat cropping system and its effect on the yield and quality of soybean produce were investigated in a vertisol area. About 25—38% of the S added was retained in the 90 cm depth of profile. Significant changes in the total S content in soil layers were recorded wherein a total of 360 kg S ha—1 or more S was applied. Maximum increase in total S content was recorded in upper layers. Soluble S accumulated more in the 30—75 cm depth; whereas, proportion of sorbed fraction of S increased with depth. Build up of S in the surface layer of the profile was mostly related to the increase in organic fraction. The S accumulation in lower layers of the profile was mostly due to increase in soluble and sorbed fractions of S. Such an increase of the S content in the soil caused an increase in seed yield, uptake of S as well as content of oil and S containing amino acids, cystine, and methionine in seed of soybean crop. 相似文献
107.
The present study aimed at determining the effect of cell volume changes on protein synthesis, measured as the incorporation
of [3H]leucine into acid-precipitable protein, in isolated hepatocytes of air-breathing walking catfish (Clarias batrachus). The rate of protein synthesis, which was recorded to be 10.02 ± 0.10 (n = 25) nmoles mg−1 cell protein h−1 in isotonic incubation conditions, increased/decreased significantly by 18 and 48%, respectively, following hypo- (−80 mOsmol l−1)/hypertonic (+80 mOsmol l−1) incubation conditions (adjusted with NaCl), with an accompanying increase/decrease of hepatic cell volume by 12 and 20%,
respectively. Similar cell volume-sensitive changes of protein synthesis were also observed when the anisotonicity of incubation
medium was adjusted with mannitol. Increase of hepatic cell volume by 9%, due to addition of glutamine plus glycine (5 mM
each) to the isotonic control incubation medium, led to a significant increase of protein synthesis by 14%. Decrease of hepatic
cell volume by 15 and 18%, due to addition of dibutyl-cAMP and adenosine in isotonic control incubation medium, led to a significant
decrease of protein synthesis by 30 and 34%, respectively. Thus, it appears that the increase/decrease of hepatic cell volume,
caused either by changing the extracellular osmolarity or by the presence of amino acids or certain other metabolites, leads
to increase/decrease of protein synthesis, respectively, and shows a direct correction (r = 0.99) between the hepatic cell volume and protein synthesis in walking catfish. These cell volume-sensitive changes of
protein synthesis probably help this walking catfish in fine tuning the different metabolic pathways for better adaptation
during cell volume changes and also to avoid the adverse affects of osmotic stress. This is the first report of cell volume-sensitive
changes of protein synthesis in hepatic cells of any teleosts. 相似文献
108.
Goutam Kumar Kundu Md. Monirul Islam Md. Foijul Hasan Samapti Saha Gouri Mondal Bijoya Paul Md. Ghulam Mustafa 《Ecology of Freshwater Fish》2020,29(2):364-376
Understanding biodiversity and community composition is a prerequisite to sustainable exploitation and conservation of fisheries. We assessed the spatial and seasonal patterns of fish community composition and biodiversity in seasonal no-take riverine sanctuaries in Bangladesh, which aim to conserve the anadromous hilsa shad (Tenualosa spp. and Hilsa keele). Fish samples were collected during monsoon, as well as pre- and postmonsoon, from five sites within two sanctuaries and one site in an open fishing area. Although total abundance was similar along the rivers, species richness was significantly higher at the open fishing site due to its connectivity to nearby habitats. The diversity apparently decreased in a downstream direction. Fish communities at two upstream sites were separated from other sites in multivariate space largely due to higher abundance of hilsa at downstream sites and presence of floodplain-oriented species at the two upstream sites. Short body length and high trophic level at all sites indicated that fish communities were overexploited. Our results also indicated that riverine hilsa sanctuaries in Bangladesh are rich in fish species diversity and support several threatened species designated by the International Union for Conservation of Nature (IUCN). Our study also suggested that since hilsa abundance shapes community patterns, it can therefore impact riverine ecosystem functioning in the sanctuary areas. The findings of this study can serve as an important baseline for future biodiversity assessment, conservation and impact assessment of conservation in rivers, and therefore help to establish multispecies ecosystem-based management of riverine fisheries around the world. 相似文献
109.
The significance of Cryptosporidium as a causative agent of diarrhea has been assessed in bovine for a period of 2 years. A total of 940 faecal samples (470 samples in each year) both from diarrhoeic and non-diarrhoeic bovine (0-12 months age) were examined during three different seasons (rainy season, summer and winter). Overall Cryptosporidium was detected in 17.46% and 18.04% cases in first and second year, respectively. Out of 50.21% diarrhoeic and 49.79% non-diarrhoeic cases Cryptosporidium was detected in 26.79% and 8.13% in first year and 27.49% and 8.59% in second year. Year did not have any significant effect on the occurrence of cryptosporidiosis in bovine during this study period. The prevalence of cryptosporidiosis, both in diarrhoeic (61.64%) and non-diarrhoeic (47.22%) cases was highest in 0-1-month age group (P<0.01). Such a high percentage of cryptosporidiosis in clinically asymptomatic animals indicated that the particular age group of animals might be reservoir for the parasite. During this study period highest prevalence was recorded in rainy season (27.55%) followed by summer (16.99%) and winter (8.71%) (P<0.01). A total of 166 positive cases were genotyped. Molecular characterization of bovine cryptosporidiosis has been carried out by PCR-RFLP analysis of SSU rRNA gene and results indicated that Cryptosporidium parvum mainly responsible for diarrhea in bovine in India. 相似文献
110.
Haque Muhammad Shahidul Saha Nihar Ranjan Islam Muhammad Tariqul Islam Muhammad Monirul Kwon Soo-Jeong Roy Swapan Kumar Woo Sun-Hee 《Journal of Crop Science and Biotechnology》2021,24(1):27-39
Journal of Crop Science and Biotechnology - Drought stress has become a significant abiotic stress for wheat in Bangladesh. This study aimed to explore drought tolerance in Bangladeshi wheat based... 相似文献