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21.
Jan  Sami  Khan  M. N.  Jan  Sofora  Zaffar  Aaqif  Rashid  Rizwan  Khan  M. A.  Sheikh  F. A.  Bhat  M. Ashraf  Mir  R. R. 《Genetic Resources and Crop Evolution》2022,69(2):661-676
Genetic Resources and Crop Evolution - Barley (Hordeum vulgare L.) is one of the principal cereal crops grown in Western-Himalayas of India. A set of 105 barley genotypes including 38...  相似文献   
22.
  1. The ocean crisis is urgent and central to human wellbeing and life on Earth; past and current activities are damaging the planet's main life support system for future generations. We are witnessing an increase in ocean heat, disturbance, acidification, bio‐invasions and nutrients, and reducing oxygen levels. Several of these act like ratchets: once detrimental or negative changes have occurred, they may lock in place and may not be reversible, especially at gross ecological and ocean process scales.
  2. Each change may represent a loss to humanity of resources, ecosystem function, oxygen production and species. The longer we pursue unsuitable actions, the more we close the path to recovery and better ocean health and greater benefits for humanity in the future.
  3. We stand at a critical juncture and have identified eight priority issues that need to be addressed in unison to help avert a potential ecological disaster in the global ocean. They form a purposely ambitious agenda for global governance and are aimed at informing decision‐makers at a high level. They should also be of interest to the general public.
  4. Of all the themes, the highest priority is to rigorously address global warming and limit surface temperature rise to 1.5°C by 2100, as warming is the pre‐eminent factor driving change in the ocean. The other themes are establishing a robust and comprehensive High Seas Treaty, enforcing existing standards for Marine Protected Areas and expanding their coverage, especially in terms of high levels of protection, adopting a precautionary pause on deep‐sea mining, ending overfishing and destructive fishing practices, radically reducing marine pollution, putting in place a financing mechanism for ocean management and protection, and lastly, scaling up science/data gathering and facilitating data sharing.
  5. By implementing all eight measures in unison, as a coordinated strategy, we can build resilience to climate change, help sustain fisheries productivity, particularly for low‐income countries dependent on fisheries, protect coasts (e.g. via soft‐engineering/habitat‐based approaches), promote mitigation (e.g. carbon storage) and enable improved adaptation to rapid global change.
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23.
The antitumor activity of the ethanolic extracts of 12 medicinal plants of Bangladesh, including the vincristine-vinblastine producing Catharanthus roseus was studied using the potato disk bioassay technique. Among these, 10 plant extracts at 25.0-microgram/disc exhibited significant inhibition of crown gall tumors caused by Agrobacterium tumefaciens.  相似文献   
24.
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   
25.
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   
26.
The objective of this work is to analyze Fe, Mn, Cr, Cd, Cu, Pb, and Zn distributions in the water column in terms of total, dissolved, and particulate concentrations in the Salado River (Santa Fe – Argentina); their relationship with total, dissolved and suspended solids; and the impact of two pollution sources on the watercourse: a stream that collects domestic and industrial wastewater discharges of the region and a direct discharge that releases urban and industrial effluents to the river. Water samples obtained from 5 surveys were analyzed. The Salado River transported a load of heavy metals that ranged from 700 g/s to 2200 g/s of Fe, 20 g/s to 60 g/s of Mn and 1 g/s to 3 g/s of Cr. Results show that most metals were found in particulate form, that the metal input from the direct discharge may be significant at low water levels, whereas a lesser impact was produced by the stream, and that both pollution sources were negligible at high water levels.  相似文献   
27.
Cr(III) ions sorption onto sawdust of spruce (Picea smithiana) has been studied thoroughly using radiotracer technique. Maximum sorption (94%) of Cr(III) ions (8.98×10?5 M) onto sorbent surface is achieved from deionized water in 20 min agitation time using 200 mg of sawdust. The sorption data followed the Freundlich, Dubinin-Radushkevich (D-R) and Langmuir isotherms. Freundlich constants l/n = 0.86 ± 0.07 and C e = 85.0 ± 25.8 mmole g?1 have been estimated. Sorption capacity, X m = 0.82± 0.3 mmole g?1, β = ?0.00356± 0.00017 kJ2 mole?2 and energy, E = 11.9± 0.3 kJ mole?1 have been evaluated using D-R isotherm. The Langmuir constants Q = 5.8± 0.2 μmole g?1 and b = (7.4± 0.5)×104 dm3 mole?1 have been calculated. The variation of sorption with temperature yields thermodynamic parameters Δ H = ?11.6± 0.3 kJ mole?1, Δ S = ?16.2± 0.9 J mole?1 K?1 and Δ G = ?6.8± 0.3 kJ mole?1 at 298 K. The negative value of enthalpy and free energy reflect the exothermic and spontaneous nature of sorption respectively. Among the anions studied oxalate, citrate, carbonate and borate have reduced the sorption. The cations Y(III), Ce(II) and Ca(II) suppressed sorption. The sawdust column can be used to separate Cr(III) ion from Cs(I), I(I),Tc (VII) and Se (IV).  相似文献   
28.
Two infectious tenosynovitis-producing viruses were isolated from tendon sheaths and synovial fluids of 59 broilers and 15 broiler breeders obtained from different flocks in Egypt during June to October 1983. The viruses grew well on the chorioallantoic membrane of developing chicken embryos, produced small localized white pock lesions with oedematous swellings at the inoculation sites and death of most of the embryos 72 to 96 hours post-inoculation. They also induced cytopathic effect in chicken embryo rough, Vero and MS cell lines. The viruses were neutralized by reovirus S1133 antiserum, both in tissue culture and. on the chorioallantoic membrane. Inoculation of the viruses into 2-day-old broiler chicks via the foot pad, intramuscular and oral routes reproduced the disease with the development of characteristic clinical, pathological and serological responses. The infection was transmitted to in-contact control chicks. This is the first report of the disease and of the isolation and identification of the causative virus in Egypt.  相似文献   
29.
Avian pneumovirus (APV) or turkey rhinotracheitis virus (TRTV) is an important respiratory pathogen of domesticated poultry in many countries in Europe, Africa, and Asia. Until recently, the United States was considered free of APV. In late 1996, an atypical upper respiratory tract infection appeared in turkey flocks in Colorado and shortly thereafter in turkey flocks in Minnesota. An avian pneumovirus (APV-US) that was serologically distinct from the previously described TRTV was isolated as the primary cause of the new syndrome. The nucleotide sequence of a fragment of the APV-US fusion gene was determined and used to develop a polymerase chain reaction-based assay that specifically detects APV-US viral nucleic acid sequences in RNA extracts of tracheal swabs and turbinate homogenates. The assay is highly sensitive in that it can detect <0.01 TCID50 of APV. The availability of this assay enables the rapid and accurate determination of APV-US in infected poultry flocks.  相似文献   
30.
Summary Three groups of Boran cattle were maintained under different trypanocidal drug regimes for 29 months in an area of “medium” tsetse challenge. The development of immunity to trypanosomiasis in the cattle was assessed on the basis of changes in trypanocidal drug requirement, development of parasitaemia, ability to maintain normal blood values, growth and response to challenge after the withdrawal of the drugs. Observations were also made on serum antibody content by immunofluorescence and on serum immunoglobulin levels. Cattle treated with Berenil on the development of clinical disease developed a partial immunity to trypanosomiasis after two years. Cattle treated as a group with Berenil on the development of patent parasitaemia in any one animal of the group did not develop immunity. Cattle treated as a group with Samorin using the same criterion for treatment developed a degree of immunity to the disease. It was concluded that group treatment with Samorin was the most suitable of the three regimes examined for the maintenance of beef cattle in a tsetse infested area.
Resumen Se mantuvieron tres grupos de ganado Boran durante 29 meses bajo differentes regímenes terapéuticos en un área donde la concentración de moscas tsetse era mediana. Se llevó a cabo la evaluación del desarrollo de la inmunidad contra la tripanosomiasis teniendo como base los diferentes cambios en el requerimiento de drogas, desarrollo de parasitemia, abilidad para mantener los valores sanguíneos normales, crecimiento y respuestas a la descarga de parásitos después del retiro de la terápia. Se hicieron también observaciones del nivel de anticuerpos séricos por inmunofluorescencia y se determinó el nivel de inmunoglobulinas. Los animales tratados con Berenil cuando mostraban signos clínicos de la enfermedad, desarrollaron una inmunidad parcial a la tripanosomiasis después de dos a?os. Los animales tratados en grupo con Berenil cuando se detectó parasitemia en cualquier animal del grupo no desarrollaron inmunidad. El ganado tratado con Samorin en base de grupo siguiendo el mismo criterio para el tratamiento, desarrolló cierto grado de resistencia a la enfermedad. Se concluye que el tratamiento de grupo utilizando Samorin fue el mejor de los tres regímenes estudiados para el mantenimiento de ganado de carne en un área infestada de moscas tstse.

Résumé Trois groupes de bovins Boran ont été maintenus vingt neuf mois, sous différents traitements trypanocides, dans une zone “moyennement” infestée de tsé-tsé. Le développement de l'immunité à la trypanosomiase a été évalué à partir des changements dans les besoins en trypanocides, du développement de la parasitémie, de l'aptitude à maintenir les valuers normales du sang, de la croissance et de la réaction à l'infection après la suppression des médicaments. Des observations ont aussi été faites sur la présence d'anticorps sériques par immunofluorescence et sur les teneurs en immunoglobines sériques. Le bétail traité au Berenil à l'apparition de signes cliniques a été partiellement immunisé au bout de deux ans. Dans le groupe du bétail traité au Berenil à l'apparition d'une parasitémie évidente, aucun animal n'a présenté d'immunité. Le groupe de bovins traité au Samorin, selon les nêmes critères a été bien immunisé.
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