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151.
Muneshwar Singh Samaresh Kundu Ashis K. Biswas Jayanta K. Saha Awadhesh K. Tripathi Chuni L. Acharya 《植物养料与土壤学杂志》2004,167(5):577-583
A computational exercise was undertaken to quantify the percent N derived from atmosphere %Ndfa) in soybean and consequent N benefit from biological N2‐fixation process annually accrued to the soil by the soybean crop using average annual N‐input/‐output balance sheet from a 7 yr old soybean‐wheat continuous rotational experiment on a Typic Haplustert. The experiment was conducted with 16 treatments comprised of combinations of four annual rates of farmyard manure (FYM ? 0, 4, 8, and 16 t ha–1) and four annual rates of fertilizer N (? 0, 72.5, 145, and 230 kg N ha–1) applications. The estimated N contributed through residual biomass of soybean (RBNS) consisting of leaf fall, root, nodules, and rhizodeposition varied in the ranges of 7.02–16.94, 11.65–28.83, 3.31–8.91, and 11.3–23.8 kg N ha–1 yr–1, respectively. A linear relationship was observed between RBNS and harvested biomass N (HBNS) of soybean in the form of RBNS = 0.461 × HBNS – 20.67 (r = 0.989, P < 0.01), indicating that for each 100 kg N assimilated by the harvested biomass of soybean, 25.4 kg N was added to the soil through residual biomass. The Ndfa values ranged between 13% and 81% depending upon the annual rates of application of fertilizer N and FYM. As per the main effects, the %Ndfa declined from 76.4 to 26.0 with the increase in annual fertilizer‐N application from 0 to 230 kg N ha–1, whereas %Ndfa increased from 40.8 to 65.8 with the increase in FYM rates from 0 to 16 t ha–1, respectively. The N benefit from biological N2 fixation accrued to the soil through residual biomass of soybean ranged from 7.6 to 53.7 kg N ha–1 yr–1. The treatments having %Ndfa values higher than 78 showed considerable annual contribution of N from N2 fixation to the soil which were sufficient enough to offset the quantity of N removed from the soil (i.e., native soil N / FYM‐N / fertilizer‐N) with harvested biomass of soybean. 相似文献
152.
Biswas Md. Jamil Hossain Mainali Bishwo Inskeep Jess R. Gaire Sushil K. Cross Dominic Stringer Lloyd D. Taylor Phillip W. Rempoulakis Polychronis 《Journal of pest science》2022,95(1):291-301
Journal of Pest Science - Queensland fruit fly (Q-fly), Bactrocera tryoni (Froggatt), is a significant pest of horticultural crops in Australia. The sterile insect technique (SIT) is currently... 相似文献
153.
Direct observation of percolation in a manganite thin film 总被引:1,自引:0,他引:1
Upon cooling, the isolated ferromagnetic domains in thin films of La0.33Pr0.34Ca0.33MnO3 start to grow and merge at the metal-insulator transition temperature TP1, leading to a steep drop in resistivity, and continue to grow far below TP1. In contrast, upon warming, the ferromagnetic domain size remains unchanged until near the transition temperature. The jump in the resistivity results from the decrease in the average magnetization. The ferromagnetic domains almost disappear at a temperature TP2 higher than TP1, showing a local magnetic hysteresis in agreement with the resistivity hysteresis. Even well above TP2, some ferromagnetic domains with higher transition temperatures are observed, indicating magnetic inhomogeneity. These results may shed more light on the origin of the magnetoresistance in these materials. 相似文献
154.
Virulence gene and antibiotic resistance profile of Shiga-toxin-producing Escherichia coli prevalent in captive yaks (Poephagus grunniens) 总被引:2,自引:0,他引:2
155.
Thirty spring wheat varieties were evaluated and classified into eight different groups on the basis of their grain yield performance and phosphorus (P) uptake using Metroglyph analysis. Significant variability was observed for grain and biomass yield, plant height, P content in grain and straw, total P uptake and phosphorus harvest index and P use efficiency traits. Varieties WH 711 and PBW 343 exhibited high grain yield as well as high P uptake (HGY-HP). WH 283 and UP 2425 with high index score of 19 and 16 respectively, constituted the high grain yield-medium P uptake (HGYMP) group. Both these varieties, though had similar grain yield of 5348 kg/ha, but WH 283 (12.64 kg/ha) utilized much lower P as compared to UP 2425 (16.94 kg/ha). Moreover, WH 283 (81.64) also showed higher values for phosphorus harvest index (PHI) than UP 2425 (67.88%). P uptake of WH 283 was comparable with that of Raj 3765 (10.78 kg/ha) and grouped into high grain yield and low P uptake (HGY-LP) group. The grain yield performance of these two varieties with a relatively low P uptake is reflected in their high index score for P use efficiency thus, earmarking them for low P regimes. Variety HW 2006, despite low grain yields of 4665 kg/ha had high index score of 16 due to its higher value for Phosphorus Biological (PBER) and Economic Yield (PEER) Efficiency Ratio as it has effected least (7.18 kg/ha) P mobilization. In addition high P translocation in the grain was also observed for this variety. Inter-mating of genotypes like HW 2006, UP 2338 and HW 2016 with those belonging to HGY-HP (PBW 343 and WH 711) and HGY-LP (Raj 3765 and WH 283) would be an ideal strategy to develop the cultivars for efficient phosphorus use. 相似文献
156.
Himel Barua Paritosh Kumar Biswas Kaisar Ali Talukder Katharina E.P. Olsen Jens Peter Christensen 《Veterinary microbiology》2014,168(2-4):372-380
We investigated Salmonella enterica isolates from human clinical cases of gastroenteritis to determine the distribution of non-typhoidal Salmonella serovars in the human population, and compared them to isolates originating from poultry by serotyping, phage typing, plasmid profiling, pulsed-field gel electrophoresis (PFGE) and multi-locus sequence typing (MLST) to evaluate the potential role of poultry in human non-typhoidal salmonellosis in Bangladesh. Nine different serovars were identified among the human isolates of which Salmonella Paratyphi B var Java (S. Java), S. Kentucky, S. Enteritidis, S. Virchow and S. Weltevreden also were commonly isolated from poultry. The poultry isolates belonging to S. Java, S. Kentucky and S. Enteritidis were indistinguishable from human isolates or genetically closely related, based on PFGE profiles and MLST. S. Kentucky clone ST198 and S. Java clone ST43 both well-known cause of human infections were also isolated from poultry. 相似文献
157.
Angshuman Biswas Mitali Pramanik Samita Kundu Sumedha Roy Jhuma De Arun Kumar Ray 《Fish physiology and biochemistry》2006,32(1):73-81
Triploid Heteropneustes fossilis (Bloch) showed sterility and higher growth potential than the normal diploid fish. Activities of some metabolic enzymes such
as cytosolic NADP-malate dehydrogenase (NADP-MDH), mitochondrial NAD-malate dehydrogenase (NAD-MDH) and glutamate pyruvate
transaminase (GPT) were evaluated in liver, brain and kidney along with glucose-6-phosphate dehydrogenase (G-6-P D) in ovary
of female triploid catfish. Activities of these enzymes showed distinct seasonal periodicity, mostly with highest activities
in prespawning and spawning periods, in both diploid and triploid catfish but differed in magnitude. In triploid liver, GPT
showed higher activity than the diploid counterpart in prespawning and spawning periods. On the contrary, mitochondrial NAD-MDH
and cytosolic NADP-MDH in this organ showed a consistent lower activity than the diploid in all stages or in some stages of
reproductive cycle respectively. Interestingly, none of the enzymes in brain and kidney of triploid female catfish showed
significant changes in comparison to the diploid counterpart. The triploid ovary maintained a significantly lower level of
G-6-P D activity throughout the resting, preparatory and pre-spawning periods compared to the diploid ovary. Lower level of
malic enzymes (NAD-MDH and NADP-MDH) in liver and G-6-P D in ovary are in close synchrony with lower level of estradiol-17β
in plasma of female triploids as found in earlier study. 相似文献
158.
J.K. Biswas 《Aquaculture (Amsterdam, Netherlands)》2006,261(3):952-959
Advanced fry of common carp (1.6 ± 0.2 g) were reared in experimental outdoor tanks (4500 l; 3 × 1.5 × 1 m) for 312 or 151 days under six stocking conditions of 8, 13, 16, 32, 48 and 64 fish per tank for ascertaining the threshold and critical levels of ammonium and, hence, to recommend the optimum stocking density of common carp for culture under rearing stage conditions. The samples of water were monitored from each tank at regular intervals for water quality parameters as well as for ammonium concentrations. Fishes were harvested at the end of the experiment. The results revealed a significant decrease in fish growth as stocking density increased. Absence of mortality and favorable growth resulted in maximum fish biomass at the stocking density of 16 fish/tank, but the heavy mortality and stunted growth caused the poor total fish biomass in the highest stocking density employed. The interactions between ammonium and fish growth were expressed at three different concentration levels of ammonium: (a) favorable concentration range (0.262-0.294 mg l− 1), (b) growth inhibiting concentration range (0.313-0.322 mg l− 1) and (c) lethal concentration range (0.323-0.422 mg l− 1). The ambient ammonium concentrations of 0.313 mg l− 1 (or equivalent ammonia concentration of 0.0342 mg l− 1) and 0.323 mg l− 1 (or equivalent ammonia concentration of 0.043 mg l− 1), observed for stocking density ranging from 17 to 19 fish per tank, were considered to be the threshold and critical levels of ammonium that caused growth inhibition and mortality of fish. Fish mortality was higher when the ratio of DO to ammonium remained quite low (< 15), but no mortality occurred with higher ratio. Considering the economic viability of the production system, this appears that the optimum fish stocking density would be around SD 16 (equivalent to 210 g m− 3). 相似文献
159.
Merih Otker Uslu Mohammad Feisal Rahman Saad Y. Jasim Ernest K. Yanful Nihar Biswas 《Water, air, and soil pollution》2012,223(6):3173-3180
The reactivity of selected compounds in Lake Huron water was evaluated during ozone/hydrogen peroxide-based advanced oxidation process (AOP) and conventional treatment (coagulation?Csedimentation?Cfiltration). Elimination of these compounds via advanced oxidation and conventional treatment processes were strongly related to their molecular structures. Overall removal of target compounds was quite similar in effluents from both the AOP and the combined treatment process (AOP?+?conventional) with the exception of fluoxetine. Reaction rate constants for the decomposition of the target compounds were substantially higher during AOP compared to conventional treatment alone. 相似文献
160.
C. H. Bock T. T. Endalew B. K. Biswas A. K. Yadav V. Sitther M. W. Hotchkiss K. L. Stevenson B. W. Wood 《Forest Pathology》2014,44(4):266-275
Fusicladium effusum infects pecan causing yield loss, but no information is available on the genetic diversity of F. effusum. Randomly amplified polymorphic DNAs (RAPDs) and universally primed polymerase chain reaction (UP‐PCR) were compared to detect polymorphisms on a group of 20 isolates of F. effusum from 11 geographical locations in the southeastern USA. Two tests (run 1 and 2) of both the RAPD and UP‐PCRs were conducted to assess the repeatability of the methods, and the markers scored on agarose gels. In addition, the UP‐PCR markers from run 1 were scored using an automated capillary system. Both RAPDs and UP‐PCR markers detected a high level of polymorphism among the scored markers (92 and 91% of RAPD markers, and 86 and 87% of manually scored UP‐PCR markers in run 1 and 2 were polymorphic, respectively; 93% of UP‐PCR markers were polymorphic when scored using the automated system). Unweighted paired group method of arithmetic averages (UPGMA) analysis showed both RAPDs and UP‐PCR markers individually identified each isolate, producing three groupings, but only the groupings based on run 1 and 2 of the UP‐PCR contained the same isolates. Bootstrap analysis based on the Dice coefficient produced phenograms from the UP‐PCR data with weak to moderate node support (≥54) for the primary branch, but no support for the RAPDs data (≤34). A Mantel test of runs 1 and 2 using RAPDs or UP‐PCR showed good agreement (r = 0.8761 and 0.8289, p < 0.0001), but poor agreement between RAPDs and UP‐PCR. UP‐PCR results based on the interisolate Dice coefficients showed a weak to strong association with distance. Based on these results, both RAPDs and UP‐PCR markers were capable of demonstrating polymorphisms and identifying relationships among isolates of F. effusum; however, UP‐PCR markers appear to be more reliable. 相似文献