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101.
102.
以提高金针菇单瓶产量为目的,以常规生产为对照,通过单因素试验、Plackett-Burman试验、响应面优化法、验证试验分析培养基装瓶量、灭菌前pH、接种量、搔菌深度、搔菌补水量对金针菇单瓶平均产量的影响。单因素试验结果表明,单瓶平均产量分别在装瓶量1 000 g、灭菌前pH值 6.80、接种量35 mL、搔菌深度10 mm、搔菌补水量10 mL时达到最大值;Plackett-Burman试验表明装瓶量、灭菌前pH和搔菌补水量是影响金针菇单瓶平均产量的关键因素;响应面优化法预测的最优化条件为培养基装瓶量1 004.05 g、灭菌前pH值6.83、搔菌补水量11.41 mL,金针菇单瓶平均产量为473.81 g;结合单因素试验及响应面预测,将验证试验设置为培养基装瓶量(1 000±5) g、灭菌前pH值(6.80±0.10)、搔菌补水量(11±1) mL、搔菌深度(10±2) mm、接种量(35±5) mL,金针菇单瓶平均产量为466.36 g,比对照组提高11.63 g,与预测值接近,相对误差为1.57%,试验设计符合生产需求。 相似文献
103.
分析了田间栽培条件下2年生转UGPase基因喜树与对照株的木材化学成分与生长速率。结果表明,转UGPase基因喜树综纤维素含量达到78.87%,比对照株相比提高了2.23%;纤维素含量为36.34%,与对照株相比没有明显提高;木质素含量为15.05%,较对照株降低了1.75%;两者的灰分含量均较低且无显著差异;冷、热水抽提物含量为7.62%与10.17%,分别提高了2.04%与2.13%;1% NaOH抽提物含量为27.13%,提高了1.27%。因此,就综纤维素、木质素、灰分含量而言,转UGPase基因喜树为优质纸浆材,水抽提物和1% NaOH抽提物的含量略高,在纸浆生产中需加以重视。本文还对转UGPase基因喜树与对照株的株高、基径、生物量进行了动态监测,结果表明,从5月25日到11月10日的生长季中,其株高平均增加121 cm,对照株平均仅67.8 cm,株高生长速率提高了78.47%;基径平均增加1 792 cm,对照株平均仅0.532 8 cm,提高了236.37%;地上部分生物量的积累与对照相比提高了322.61%,即转入UGPase基因使喜树生长速率显著提高。因此,虽然转UGPase基因喜树的综纤维素和纤维素含量没有明显提高,但其生长速率快,生物量增长显著,间接提高了纤维素与喜树碱的产量。因此,转基因喜树较普通喜树更符合纸浆材速生、纤维素含量高和产量高、木质素含量低的基本要求,可在生产中进一步推广。 相似文献
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106.
57份苎麻种质资源主要农艺性状及纤维品质鉴定评价 总被引:1,自引:0,他引:1
对57份苎麻种质的主要农艺性状和纤维品质性状进行了鉴定评价。结果筛选出高产苎麻种质10份(原麻产量≥2000 kg/hm2),纤维品质优良的种质7份(纤维细度≥2000 m/g),鲜皮出麻率≥12.5%的苎麻种质20份,炼折率超过65%的苎麻种质有10份,按照苎麻优异种质评价规范,满足高产和出麻率高2个优良指标的种质7份,满足优质和鲜皮出麻率高2个优良指标的种质1份。 相似文献
107.
Julien Cappelle Delong Zhao Marius Gilbert Martha I. Nelson Scott H. Newman John Y. Takekawa Nicolas Gaidet Diann J. Prosser Ying Liu Peng Li Yuelong Shu Xiangming Xiao 《EcoHealth》2014,11(1):109-119
For decades, southern China has been considered to be an important source for emerging influenza viruses since key hosts live together in high densities in areas with intensive agriculture. However, the underlying conditions of emergence and spread of avian influenza viruses (AIV) have not been studied in detail, particularly the complex spatiotemporal interplay of viral transmission between wild and domestic ducks, two major actors of AIV epidemiology. In this synthesis, we examine the risks of avian influenza spread in Poyang Lake, an area of intensive free-ranging duck production and large numbers of wild waterfowl. Our synthesis shows that farming of free-grazing domestic ducks is intensive in this area and synchronized with wild duck migration. The presence of juvenile domestic ducks in harvested paddy fields prior to the arrival and departure of migrant ducks in the same fields may amplify the risk of AIV circulation and facilitate the transmission between wild and domestic populations. We provide evidence associating wild ducks migration with the spread of H5N1 in the spring of 2008 from southern China to South Korea, Russia, and Japan, supported by documented wild duck movements and phylogenetic analyses of highly pathogenic avian influenza H5N1 sequences. We suggest that prevention measures based on a modification of agricultural practices may be implemented in these areas to reduce the intensity of AIV transmission between wild and domestic ducks. This would require involving all local stakeholders to discuss feasible and acceptable solutions. 相似文献
108.
Alkaline phosphatase(AKP),from the succus entericus of silkworm,was purified using 10%-50% ammonium sulfate fractions,ion exchange chromatography Of DEAE-Sepharose,and size exclusion chromatography of Sephacryl S-200.The purification fold was 464 times and specified activity was 3936 U/mg.Optimum pH value of the phosphatase was 10.5,and was stable between pH 7.5 and 11.The optimum temperature of the phosphatase was 40℃ and it was unstable over 50℃.Km value of the phosphatase was 1.25 mmol/L.In a given condition,the phosphatase was selectively modified by PCMB,NBS,PMSE TNBS,SUAN,DTT,BrAc,and IAc,the results indicate that PMSF,SUA,BrAc,IAc,and TNBS could Obviously inhibit the activity of the phosphatase,and the degree of inhibition depended on the concentration of these reagents.There was little effect on the activity of phosphatase after treatment by PMSF,DTT,and NBT.We primarily conclude that mercapto and imidazole are essential for AKP from silkworm.Also,Lys residue and disulfide bands are necessary to protect the catalysis of the AKP. 相似文献
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Separation strategies based on size-selective precipitation of DNA fragments with polyethylene glycol (PEG) have been used for achieving desired DNA interval in automated sample preparation for next-generation sequencing. By varying PEG concentration, DNA fragments of different sizes can be precipitated onto surfaces of carboxyl-coated paramagnetic particles selectively, and therefore, the desired DNA interval can be obtained. However, one of the crucial points in this approach is to determine the critical PEG concentration for DNA fragment of a certain size. The aim of this work was to develop a convenient and reliable method for accurately determining the critical PEG concentration. In our method, at a fixed concentration of sodium chloride (NaCl), recovered DNA samples obtained with different PEG concentrations were directly quantified, and their concentrations as a function of the PEG concentration were fitted by the logistic function. The critical PEG value was easily and accurately determined from the fitted logistic function. The repeatability and stability of the critical PEG value were assessed, showing an excellent reliability of the method. Based on this method, critical PEG values of different-size DNA fragments were determined at different NaCl concentrations. The effectiveness of the method was also demonstrated by selective precipitation of DNA fragments. 相似文献