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31.
K. P. Akhtar G. Sarwar H. M.I. Arshad 《Archives Of Phytopathology And Plant Protection》2013,46(4):320-330
Charcoal rot caused by Macrophomina phaseolina is a serious disease of sesame in Pakistan. M. phaseolina sesame isolate was subjected to growth rate test at 10, 15, 20, 25, 30, 35 and 40°C. The optimum temperature for fungal growth and microsclerotia production was found to be 30–35°C. Gray to black, radial fungal colonies with intermediate mycelial growth and jet black oval to round microsclerotia were observed at this optimum range. M. phaseolina was found to be pathogenic against all the 18 tested plant species and this pathogenicity proved its necrophytic behavior. Seed infection efficiency of M. phaseolina was 100% with significant reduction in seed index. For two consecutive years 21 mutants/varieties were screened in the field for their reactions to charcoal rot disease. During 2007 three mutants NS11704S1, NS11304S2 and NS26004 were ranked as resistant while others were moderately resistant to highly susceptible. During 2008 all mutants showed a susceptible to highly susceptible reaction with variable disease reactions. All over screening results revealed that four mutants viz, NS13P1, NS163-1, NS270P1 and NS26004 showed about 50% stand with consistent performance during both years under optimum disease conditions and can be used to manage the disease following the disease management strategies, however in the future improvement for high seed yield along with resistance is a prerequisite for sustainable high production. 相似文献
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Akhtar A Fuchs E Mitchison T Shaw RJ St Johnston D Strasser A Taylor S Walczak C Zerial M 《Nature reviews. Molecular cell biology》2011,12(10):669-674
Nature Reviews Molecular Cell Biology celebrated its 10-year anniversary during this past year with a series of specially commissioned articles. To complement this, here we have asked researchers from across the field for their insights into how molecular cell biology research has evolved during this past decade, the key concepts that have emerged and the most promising interfaces that have developed. Their comments highlight the broad impact that particular advances have had, some of the basic understanding that we still require, and the collaborative approaches that will be essential for driving the field forward. 相似文献
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Arjumand Sohaila Shiyam Sunder Tikmani Iqtidar Ahmed Khan Huba Atiq Ali Syed Muhammad Akhtar Prem Kumar Kishwer Kumar 《PloS one》2014,9(7)
Introduction
Retinopathy of prematurity (ROP) is a treatable cause of blindness in neonates. In Pakistan, ROP is often not recognized early because screening and treatment programs are not yet in place in most neonatal units, even in tertiary care hospitals. It is hoped that this report will help inform medical professionals of the magnitude of the problem and help to design appropriate management strategies.Objectives
The aim was to determine the frequency of ROP in premature and very low birth weight (BW) neonates (BW<1500 g and gestational age (GA) <32 weeks).Study Design
Cross-sectional study.Study Setting
Neonatal intensive care unit (NICU) of a tertiary care hospital in Karachi, Pakistan.Study Duration
From June 2009 to May 2010.Subjects and Methods
Neonates with a Birth weight (BW) <1500 g and Gestational Age (GA) <32 weeks who were admitted to the NICU and received an eye examination, or were referred for a ROP eye examination as an outpatient, were included in the study. GA was estimated from intrauterine ultrasound findings. Neonates with major congenital malformations, syndromes or congenital cataracts or tumors of the eyes, and those that died before the eye examination or did not attend the out patients department for an eye examination, were excluded. The neonatal eye examination was performed by a trained ophthalmologist at 4 or 6 weeks of age.Results
Out of 86 neonates, ROP was identified in nine neonates (10.5%) at the first eye examination. ROP was significantly associated with BW (P = 0.037), GA (P = 0.033), and chronological age (P<0.001).Conclusions
we identified ROP in 10.5% of neonates at first eye examination. Significant associations between ROP and a GA<32 weeks and a BW<1500 g were also observed.we also stress that serial follow-up of neonates at risk for ROP is important when making a final diagnosis. 相似文献36.
Arif Muhammad Rashid Naeem Perveen Sumera Bashir Qamar Akhtar Muhammad 《Extremophiles : life under extreme conditions》2019,23(1):69-77
Extremophiles - The gene-encoding Indole-3-glycerol phosphate synthase, a key enzyme involved in the cyclization of 1-(o-carboxyphenylamino)-1-deoxyribulose 5-phosphate, from Pyrococcus furiosus... 相似文献
37.
Asim Mehmood Umal Baneen Ahmad Zaheer Muhammad Wasim Sajid Abrar Hussain Shahzad Saleem Qudsia Yousafi Hamid Rashid Hassan Riaz Awais Ihsan Farrukh Jamil Yasar Sajjad Nageena Zahid Muhammad Shahzad Anjam Muhammad Arshad Zeenat Mirza Sajjad Karim Mahmood Rasool 《Saudi Journal of Biological Sciences》2019,26(7):1485-1491
ObjectivePhosphorous is an essential micronutrient of plants and involved in critical biological functions. In nature, phosphorous is mostly present in immobilized inorganic mineral and in the fixed organic form including phytic acid and phosphoesteric compounds. However, the bioavailability of bound phosphorous could be enhanced by the use of phosphate solubilizing microorganisms such as bacteria and fungi. The phytases are widespread in an environment and have been isolated from different sources comprising bacteria and fungi.MethodologyIn current studies, we show the successful use of gamma rays and EMS (Ethyl Methane Sulphonate) mutagenesis for enhanced activity of phytases in a fungal strain Sporotrichum thermophile.ResultsWe report an improved strain ST2 that could produce a clear halo zone around the colony, up to 24 mm. The maximum enzymatic activity was found of 382 U/mL on pH 5.5. However, the phytase activity was improved to 387 U/ml at 45 °C. We also report that the mutants produced through EMS showed the greater potential for phytase production.ConclusionThe current study highlights the potential of EMS mutagenesis for strain improvement over physical mutagens. 相似文献
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The basal cut end of coppice shoot cuttings of Pongamia pinnata was treated for 24 h with 0 (water treated control) or 5.0 mmol/L of KMnO4, KCI, and KH2PO4 or 2.5 mmol/L of K2HPO4 and K2SO4. Inorganic salts of P, S, Cl and Mn significantly influenced IAA ionization and adventitious rhizogenesis. P and S salts had lower IAA ionization potential, but more pronounced effect on adventitious rhizogenesis than Cl and Mn salts. The linear regression analysis also established negative correlations between salt induced IAA ionization with various characteristics of adventitious rhizogenesis such as sprouting (r = -0.83, p < 0.05), rooting (r = -0.82, p < 0.05), root number (r = -0.95, p < 0.01), and root length (r = -0.80, p < 0.1). The implication of IAA ionization in adventitious rhizogenesis has been discussed and the possible role of inorganic salts therein suggested. 相似文献
40.
Molecular cloning of fungal xylanases: an overview 总被引:1,自引:0,他引:1
Xylanases have received great attention in the development of environment-friendly technologies in the paper and pulp industry.
Their use could greatly improve the overall lignocellulosic materials for the generation of liquid fuels and chemicals. Fungi
are widely used as xylanase producers and are generally considered as more potent producers of xylanases than bacteria and
yeasts. Large-scale production of xylanases is facilitated with the advent of genetic engineering. Recent breakthroughs in
genomics have helped to overcome the problems such as limited enzyme availability, substrate scope, and operational stability.
Genes encoding xylanases have been cloned in homologous and heterologous hosts with the objectives of overproducing the enzyme
and altering its properties to suit commercial applications. Owing to the industrial importance of xylanases, a significant
number of studies are reported on cloning and expression of the enzymes during the last few years. We, therefore, have reviewed
recent knowledge regarding cloning of fungal xylanase genes into various hosts for heterologous production. This will bring
an insight into the current status of cloning and expression of the fungal xylanases for industrial applications. 相似文献