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1.
Peroxidase from fenugreek (Trigonella foenum-graecum) seeds was highly effective in the decolorization of textile effluent. Effluent was recalcitrant to the action of fenugreek seeds peroxidase (FSP). However, in order to effectively decolorize effluent by peroxidase, the role of six redox mediators has been investigated. The maximum decolorization of textile effluent was observed in the presence of 1.0 mM 1-hydroxybenzotrizole, 0.7 mM H2O2, and 0.4 U ml?1 of FSP in the buffer of pH 5.0 at 40°C in 2.5 h. The decolorization of textile effluent in a batch process by peroxidase was 85% in 5 h, whereas the complete decolorization of textile effluent by membrane-entrapped FSP was observed within 11 h of its operation. The absorption spectra of treated effluent exhibited a marked diminution in the absorbance at different wavelengths compared to untreated effluent.  相似文献   
2.
Recent advances in sequencing technology have brought several novel platforms for marker development and subsequent genotyping. The high-throughput and cost effective marker techniques have changed the entire scenario of marker applications. The huge genotypic data obtained with next generation sequencing (NGS) also demands analytical tools, statistical advances, and comprehensive understanding to cope with breeding applications. In the present review, we discussed different available marker techniques, their strengths, and limitations. Emphasis was given on software tools, analytical pipelines, workbenches, and online resources available for marker development. Comparison of SNP genotyping involving complexity reduction techniques like GBS, RRL, RAD, and array-based platforms were presented in a view to describe suitability for specific purposes. We found that genotyping by whole genome re-sequencing has great potential, and could be a routine application in the near future with continuously decreasing cost of sequencing. Microsatellites, still a valuable option for breeders, have also advanced with NGS. Here a catalogue of tools for microsatellite evaluation in short sequence reads was provided. The most common applications of molecular marker like QTL mapping, genome-wide association mapping (GWAS), and genomic selection were highlighted. The present review will be helpful for the effective utilization of available resources and for the planning of crop improvement programs employing molecular marker techniques.  相似文献   
3.
A pot experiment was conducted to evaluate the foliar applied phosphorous with and without pre-plant dose (50 kg hac.?1) of phosphorous on growth, chlorophyll contents, gas exchange parameters and phosphorous use efficiency (PUE) of wheat. The experiment was conducted in net house at Department of Crop Physiology, University of Agriculture Faisalabad, Pakistan. Two promising wheat cultivar AARI 2011 and FSD 2008 were used as a test crop with 5 foliar phosphorus (P) rates (0, 2, 4, 6, 8 kg ha?1). The foliar applied P with pre-plant performed better than without pre-plant and control treatments. Foliar treatment of phosphorus at 6 kg ha?1 P proved to be the best among other foliar treatments followed by 8 kg ha?1 P. The foliar application of phosphorous at 6 kg hac.?1 with pre-plant soil applied P increased the shoot length, root length, shoot fresh weight, root fresh weight, shoot dry weight and root dry weight. The chlorophyll contents (Chl. a and b) were increased with the foliar application of phosphorous. The gas exchange parameters (net carbon dioxide (CO2) assimilation rate, transpiration rate, stomatal conductance and sub-stomatal CO2 rate) were significantly improved by foliar applied P. The maximum values of net CO2 assimilation rate (5.27 μ mol m?2 sec.?1), transpiration rate (3.44 μ mol m?2 sec.?1), stomatal conductance (0.81 μ mol m?2 sec.?1) and sub-stomatal CO2 (271.67 μ mol m?2 sec.?1), were recorded in the treatment where P was foliar applied at 6 kg hac.?1 with pre-plant soil applied Phosphorous. The foliar application of phosphorous with pre-plant soil applied P enhanced Phosphorous use efficiency (PUE) in both varieties. The maximum value of PUE (15.42%) was recorded in the treatment where foliar feeding of P was done at 6 kg hac.?1 with pre-plant soil applied P in both genotypes.  相似文献   
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Kalam Kohistan is a dry,temperate hilly region in the Hindu Raj Series of the Greater Hindu Kush Mountains with diverse forests.As plant distribution and composition is expression of a range of various environmental variables,ecological and floristic attributes of vegetation in the Laikot Forests were therefore evaluated via consecutive explorative trips.These forests have not been evaluated ecologically before due to harsh climatic conditions and issues of accessibility and the study in hand is one of the first in its nature.Quantitative ecological techniques were used to sample forest vegetation and identify species in quadrats of 2 m×2 m for herbs,5 m×5 m for shrubs and 10 m×10 m for trees.All the data of 195 plant species and environmental factors were analyzed via Two-way Cluster Analysis and Canonical Correspondence Analysis using PCORD and CANOCO software.Among 195 plant species from 63 families were 27 species of Asteraceae,the most-speciose family,followed by Poaceae(20 spp.).The dominant life form was therophyte(86 spp.;44%share),followed by phanerophyte(41 spp.;21%share).For the leaf size spectrum,most prevalent was nanophyll(73 spp.;44%)followed by microphyll(66 spp.,34%)and mesophyll(44 spp.;23%).Calcium carbonate,pH,potassium,sand,silt,organic matter,slope aspect and grazing significantly influenced species composition,distribution and habitat.The floristic variation in the region was diverse due to elevational and aspect gradients and thus devided into three zones.This vegetation zonation can be utilized for forest management,species and habitat conservation.Both in situ and ex situ conservation of threatened plant species may improve their conservation status in future if address properly.  相似文献   
6.
The pattern of organophosphate resistance in field populations of Helicoverpa armigera (Hübner) was monitored in Pakistan from 1994 through 1997 using an IRAC leaf-dip method. Generally, moderate to high resistance was found to an orthophosphorate, monocrotophos and to a dithiophosphorate, ethion. Resistance to the commonly used thiophosphorates, chlorpyrifos and profenofos, was very low during 1994 and 1995 but showed an upward trend during 1996 and 1997. Resistance factors to the other thiophosphorates such as quinalphos, parathion-methyl, methamidophos and triazophos remained very low. Baseline lethal concentrations for ethion, methamidophos and triazophos were at least four to five times higher than those for the other organophosphates tested, suggesting their low intrinsic efficacy against H armigera. © 1999 Society of Chemical Industry  相似文献   
7.
Two cotton (Gossypium hirsutum L.) cultivars, Kemian 1 (cool temperature-tolerant) and Sumian 15 (cool temperature-sensitive) were used to study the effects of cool temperature on carbohydrates, yield, and fiber quality in cotton bolls located at different fruiting positions (FP). Cool temperatures were created using late planting and low light. The experiment was conducted in 2010 and 2011 using two planting dates (OPD, the optimized planting date, 25 April; LPD, the late planting date, 10 June) and two shading levels of crop relative light rate (CRLR, 100 and 60%). Compared with fruiting position 1 (FP1), cotton yield and yield components (fiber quality, leaf sucrose and starch content, and fiber cellulose) were all decreased on FP3 under all treatments. Compared with OPD-CRLR 100%, other treatments (OPD-CRLR 60%, LPD-CRLR 100%, and LPD-CRLR 60%) had significantly decreased lint yield at both FPs of both cultivars, but especially at FP3 and in Sumian 15; this decrease was mainly caused by a large decline in boll number. All fiber quality indices decreased under late planting and shading except fiber length at FP1 with OPD-CRLR 60%, and a greater reduction was observed at FP3 and in Sumian 15. Sucrose content of the subtending leaf and fiber increased under LPD compared to OPD, whereas it decreased under CRLR 60% compared to CRLR 100%, which led to decreased fiber cellulose content. Therefore, shading primarily decreased the “source” sucrose content in the subtending leaf whereas late planting diminished translocation of sucrose towards cotton fiber. Notably, as planting date was delayed and light was decreased, more carbohydrates were distributed to leaf and bolls at FP1 than those at FP3, resulting in higher yield and better fiber quality at FP1, and a higher proportion of bolls and carbohydrates allocated at FP3 of Kemian 1 compared to that of Sumian 15. In conclusion, cotton yield and fiber quality were reduced less at FP1 compared to those at FP3 under low temperature and low light conditions. Thus, reduced cotton yield and fiber quality loss can be minimized by selecting low temperature tolerant cultivars under both low temperature and light conditions.  相似文献   
8.
Agricultural sector is a major source of employment and export earnings for Pakistan. Exports of Pakistan are highly concentrated in agricultural products including cotton, rice, sugar and fruit. This study analyzed comparative and competitive advantages of the main agricultural products of Pakistan, i.e. cotton, rice and tangerines. Consumption patterns of top exporting countries in each category were also analyzed. Results revealed that Pakistan had strong competitiveness for export of these commodities. Strong potential for growth in the agricultural sector of Pakistan was found and it could be optimized to raise export earnings and meet the objectives of the strategic trade policy framework(STPF) 2015-2018 of Pakistan.  相似文献   
9.
Salinity is a major abiotic stress that affects crop production throughout the world. Biochar is an activated carbon soil conditioner that can alleviate the negative impacts of salinity. The research was conducted to evaluate the ameliorative effect of 1% and 2% of biochar application on wheat seed germination and growth attributes under salinity. Both levels of biochar improved the germination and growth conditions under salinity; however, 2% biochar level was more effective compared to 1% level. Root and shoot length increased up to 23% and11% with 2% biochar, respectively. The maximum increase of 16% and 10% in leaf water potential and osmotic potential was noted with 2% biochar at 150 mM salt. The decrease in proline content and soluble sugar at 2% biochar was 51% and 27%, respectively. Decrease in superoxide dismutase activity was 15.3% at 2% level of biochar under stress biochar mitigates the negative effects of salinity and improved wheat productivity.  相似文献   
10.
Four commercial strains of chickens, namely, ISA brown leghorn (ISA), TETRA-SL brown (TETRA-SL), Lohmann brown (LB), and Lohmann LSL (LSL), were infected with a well-defined clonal culture of Histomonas meleagridis (H. meleagridis/Turkey/Austria/2922-C6/04) to investigate their susceptibility to histomonosis. Each group included 16 chickens, which were housed under the same conditions in separate pens. All chickens were infected with 10(4) histomonads orally and intracloacally at 14 days of age. No mortality or clinical signs were observed during the experiment in all birds. Three birds of each chicken strain were euthanatized on days 4, 7, 10, 14, and 21 postinfection. Incidence of histomonosis on the basis of cecal lesions was found to be 64.00% in TETRA-SL, 62.50% in LB, 53.12% in LSL, and 43.75% in ISA chickens. Fewer lesions were noticed in livers than in ceca, with an incidence of 15.62% in TETRA-SL, 9.37% in LB, and 3.12% in ISA chickens. No liver lesions were found in the LSL chickens. Statistical analysis revealed that there was no significant difference (P > 0.05) in susceptibility to experimental H. meleagridis infection based on cecal and liver involvement. Polymerase chain reaction (PCR) and immunohistochemistry were found to be reliable tools to confirm the presence of histomonads and changes in the ceca. However, some negative PCR results were recorded from the livers despite the presence of macroscopic lesions. Additionally, DNA of H. meleagridis was detected by PCR in a few of the lungs, but immunohistochemistry was negative. Nucleic acid of the protozoan parasite was not detected in samples from kidney, brain, spleen, or bursa of Fabricius. Altogether, the high susceptibility of commercial chicken lines to histomonosis could be demonstrated and characterized by severe lesions in the ceca and insignificant involvement of the liver, approaching a maximum on days 7-14 postinfection.  相似文献   
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