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Saeed Arshad Ahsan Iqbal Sehar Nawaz Nisar Ahmed 《Frontiers of Agriculture in China》2011,5(2):129-134
The availability of a genetically diverse gene pool is vitally important in varietal development. Molecular markers are being
extensively utilized to explore the genetic diversity among native and exotic germplasm. This study was designed to reveal
the genetic diversity and patterns of relationships among the 20 accessions/genotypes representative of basmati and non-basmati
rice from the existing rice gene pool using RAPD markers. Employing RAPD, 17 decamer oligonucleotide primers directed the
amplification of 116 fragments, out of which 101 were polymorphic (87.06%) while 15 fragments were monomorphic (12.93%). Similarity
coefficients had ranged from 0.47 to 0.90. The average genetic similarity was calculated 0.68 (68%). In this study, the coarse
rice genotypes showed more polymorphism (85.84%) than the fine rice genotypes (61.76%). Genotypes were clustered into 8 distinct
groups: A, B, C, D, E, F, G, and H but two genotypes, i.e., Shadab and Kangni-27 showed divergence from all the genotypes
of the groups. Therefore, these diverse genotypes may be included in future breeding programmes. 相似文献
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Ali Afzal Tanveer Hussain Mumtaz Hassan Malik Abher Rasheed Sheraz Ahmad Abdul Basit Ahsan Nazir 《Fibers and Polymers》2014,15(7):1539-1547
The aim of this study was to analyze and model the effect of knitting parameters on the air permeability of Cotton/Polyester double layer interlock knitted fabrics. Fabric samples of areal densities ranging from 315–488 g/m2 were knitted using yarns of three different cotton/polyester blends, each of two different linear densities by systematically varying knitting loop lengths for achieving different cover factors. It was found that by changing the polyester content in the inner and outer fabric layer from 52 to 65 % in the double layer knitted fabric did not have statistically significant effect on the fabric air permeability. Air permeability sharply increased with increase in knitting loop length owing to decrease in fabric areal density. Decrease in yarn linear density (tex) resulted in increase in air permeability due to decrease in areal density as well as the fabric thickness. It was concluded that response surface regression modeling could adequately model the effect of knitting parameters on the double layer knitted fabric air permeability. The model was validated by unseen data set and it was found that the actual and predicted values were in good agreement with each other with less than 10 % absolute error. Sensitivity analysis was also performed to find out the relative contribution of each input parameter on the air permeability of the double layer interlock knitted fabrics. 相似文献
14.
A trial of Avicennia officinalis L. with five different spacings was conducted in the newly accreted lands along the western coastline(Patuakhali district) of Bangladesh since 1993 to assess growth performance and the effect of spacing on tree growth. Data on tree density, height, diameter, bole height, crown diameter were recorded and analyzed when the stand was 19 years old. Mean height ranged from 12.89-13.52 m and diameter at breast height(dbh) from 26.57-32.16 cm in plots of different spacings. The mean annual height increment ranged from 0.67-0.71 m, mean annual diameter increment from 1.40-1.69 cm and wood volume from 6.02-10.04 m3·ha-1·a-1 in different treatments. Significantly greater diameter(32.16 cm) and wood volume(10.04 m3?ha-1?a-1) were obtained with wider(2.13 m × 2.13 m) spacing than with closer spacings. But tree growth was unaffected by other spacings. Growth data were also recorded from other A. officinalis plantations raised by Forest Department(FD) on different islands in Patuakhali and Bhola districts of Bangladesh. At these sites, mean annual height increment ranged from 0.33-0.62 m, mean annual diameter increment from 0.72-1.37 cm and wood volume from 1.55-5.73 m3?ha-1?a-1. The growth performance of A. officinalis indicated that the newly accreted lands along the western shoreline may be suitable for raising Avicennia plantations for the enrichment of coastal vegetation. 相似文献
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Hina Ali Muhammad Ahsan ul Haq Tariq Mahmud Shah Mehboob ur Rahman Weidong Chen 《European journal of plant pathology / European Foundation for Plant Pathology》2012,132(2):237-244
DNA markers in chickpea, targetting resistance genes for different races of Fusarium oxysporum f.sp. ciceris (Foc), have been identified in chickpea, but validation of these markers is essential for effective use in resistance breeding.
In view of this, different simple sequence repeats (SSR) markers were analysed in Pakistani germplasm including induced mutants
and some local lines. Most of the SSR markers showed good correlation with phenotypic evaluation of genotypes to different
races of Foc and may be used effectively in resistance breeding, except those markers for race 3. Markers for race 3 showed
deviations from phenotypic data and the reason might be that race 3 is actually Fusarium proliferatum as reported recently and resistance to this race might involve some other major resistance genes. Poor correlation of markers
with foc-3 on LG2 in our study and a recent report of independent segregation of foc-2 and foc-3 in near isogenic lines suggested that linkage distances among different resistance genes need further investigation. Moreover
three Pakistani mutant lines (97477, CM444/92 and CM368/93) depicted high levels of resistance to Foc races and can be deployed
as a valuable source in resistance breeding programmes. 相似文献
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Lisa Myrseth Hemmingsen Kjersti Julin Luqman Ahsan Purusotam Basnet Mona Johannessen Nataa kalko-Basnet 《Marine drugs》2021,19(5)
Burns and other skin injuries are growing concerns as well as challenges in an era of antimicrobial resistance. Novel treatment options to improve the prevention and eradication of infectious skin biofilm-producing pathogens, while enhancing wound healing, are urgently needed for the timely treatment of infection-prone injuries. Treatment of acute skin injuries requires tailoring of formulation to assure both proper skin retention and the appropriate release of incorporated antimicrobials. The challenge remains to formulate antimicrobials with low water solubility, which often requires carriers as the primary vehicle, followed by a secondary skin-friendly vehicle. We focused on widely used chlorhexidine formulated in the chitosan-infused nanocarriers, chitosomes, incorporated into chitosan hydrogel for improved treatment of skin injuries. To prove our hypothesis, lipid nanocarriers and chitosan-comprising nanocarriers (≈250 nm) with membrane-active antimicrobial chlorhexidine were optimized and incorporated into chitosan hydrogel. The biological and antibacterial effects of both vesicles and a vesicles-in-hydrogel system were evaluated. The chitosomes-in-chitosan hydrogel formulation demonstrated promising physical properties and were proven safe. Additionally, the chitosan-based systems, both chitosomes and chitosan hydrogel, showed an improved antimicrobial effect against S. aureus and S. epidermidis compared to the formulations without chitosan. The novel formulation could serve as a foundation for infection prevention and bacterial eradication in acute wounds. 相似文献
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Hang Liu Jian Ma Yang Tu Jing Zhu Puyang Ding Jiajun Liu Ting Li Yaya Zou Ahsan Habib Yang Mu Huaping Tang Qiantao Jiang Yaxi Liu Guoyue Chen Youliang Zheng Yuming Wei Xiujin Lan 《Plant Breeding》2020,139(2):284-294
Spike density (SD), an important spike morphological trait associated with wheat yield, is the spikelet number per spike (SNS) divided by spike length (SL). In this study, phenotypic data from eight environments were collected and a recombinant inbred line population (RIL) constructed by the wheat line 20828 and the cultivar 'Chuannong16' and a Wheat55K SNP array-based constructed genetic linkage map were used to identify SD quantitative trait locus (QTL). Correlation between SD and other agronomic traits was calculated. Genes associated with plant growth and development for major loci were predicted. The results showed that 24 QTLs associated with SD were detected in eight environments. Among them, three major QTL, namely QSd.sicau-5B.2, QSd.sicau-2D.3 and QSd.sicau-4B.1, explained up to 35.62%, 14.21% and 11.23% of phenotypic variation, respectively. The positive alleles of them were all derived from 'Chuannong16'. The significant relationships between SD and other agronomic traits were detected and discussed. Taken together, the stably expressed SD QTL under different environments identified in this study provided theoretical guidance for further fine mapping and germplasm improvement. 相似文献
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Muhammad Ahsan Raza Asif Saeed Hassan Munir Khurram Ziaf Amir Shakeel Nadeem Saeed 《Archives of Agronomy and Soil Science》2017,63(4):501-512
The experiment containing three replicates of completely randomized factorial treatments was conducted in a glasshouse under controlled conditions with three simulated soil salinity levels (control, 10 and 15 dS m?1). Morpho-physiological traits (i.e. lengths, fresh weights and dry weights of root and shoot, number of leaves, root/shoot ratio, shoot Na+ accumulation, K+/Na+ ratio, Ca2+/Na+ ratio, membrane stability index, lycopene contents, chlorophyll-a and -b) were recorded to determine mechanism of salt tolerance of tomato at seedling stage. Principal component analysis (PCA) was used to express a three-way interaction of genotype × salinity level × traits that scattered the 25 tomato genotypes based on their morpho-physiological response to different NaCl levels. The negative association of Na+ with all other traits except root/shoot ratio and the morpho-physiological response trend of genotypes exposed that probable mechanism of salt tolerance was initially Na+ exclusion by abscising older leaves to have younger physiologically energetic, and lastly a higher activity of plants for root development to sustain them in saline soil. PCA three-way biplot efficiently recognized ANAHU, LA-2821, LO-2752, LO-2707, PB-017909, LO-2831-23 and 017860 as salt tolerant genotypes. On the other hand, ZARNITZA, GLACIER, LO-2692, LO-2576, BL-1079, 006233, 006232, 017856, NUTYT-701 and NAGINA were found to be salt susceptible. 相似文献
19.
Biochemical impacts of salinity on the catfish,Heteropneustes fossilis (Bloch, 1794), and possibility of their farming at low saline water
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Mirja Kaizer Ahmmed Fatema Ahmmed Kazi Ahmed Kabir Md. Faisal Sk. Istiaque Ahmed Md. Nazmul Ahsan 《Aquaculture Research》2017,48(8):4251-4261
Although a stenohaline freshwater fish, the stinging catfish Heteropneustes fossilis, is also available in the freshwater fringes of the coastal areas of Bangladesh, the tolerance of this species to variable environmental salinity has not been thoroughly investigated. Based on median lethal salinity (MLS‐50 96 h), three sublethal salinity levels (3 ppt, 6 ppt and 9 ppt) and a control (0 ppt), each with three replications were selected to observe the effects of mildly brackish conditions on the fish for a period of 90‐day exposure. Better growth and survival were found up to 6 ppt compared with control. Salinity more than 6 ppt appeared unsuitable for H. fossilis fingerling due to increased mortality and reduced growth. To determine biochemical alterations, a few important physiological parameters were observed after 90 days of exposure. Glycogen level of liver and muscle in the fish reared at 9 ppt salinity decreased significantly (P < 0.05) as compared to the control. Glucose level in blood and liver was also found to be increased in fish with increase in salinity. ALP and ATPase activities were reduced significantly in both muscle and liver tissues at higher salinity, indicating the stress mitigation effect. However, all the biochemical parameters were found in normal condition up to 6 ppt compared with control. This evidence suggests that H. fossilis can sustain and grow well below 6 ppt and can be a potential candidate for culture in coastal areas after heavy downpour when the salinities level falls to 6 ppt or lower. 相似文献
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海栖热袍菌极端耐热木聚糖酶B的提纯 总被引:6,自引:0,他引:6
克隆并在大肠杆菌中表达的海栖热袍菌的 xyn B基因 ,其表达产物木聚糖酶 B的 C 末端带有 6×His标签 ,研究了这种基因重组酶的提纯方法。通过对粗酶提取液的热变性处理 ,Ni NTA亲和柱层析和离子柱层析 ,最终得到了电泳纯的木聚糖酶 B,提纯倍数 4 4.4 ,得率 11。SDS PAGE法测定木聚糖酶 B的相对分子质量为 4 2 ku,与理论推算值 4 2 333u相吻合 相似文献