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1.
[Objective] The aim of this study is to establish an method for cotton metabolites identification by ultra-performance liquid chromatography-electrospray ionization-mass spectrometry (UPLC-ESI-MS) analysis, and to investigate the adduct types, dominant adducts and appropriate ESI ion modes of cotton secondary metabolites under the determined UPLC and ESI conditions. [Method] UPLC-ESI-MS was employed to analyze 18 cotton metabolite standards, Online XCMS software was used to extract the nontargeted mass spectrum data, and MATLAB software was used to prepare calculation programs for the identification method of cotton metabolite standards. [Result] A high-throughput identification method of cotton secondary metabolite, named POSid and NEGid separately for the positive and negative ESI modes, was established based on the calculated accurate molecular weight. In the determined UPLC condition and positive and negative ESI mode, 14 cotton metabolite standards were correctly identified. There found 6 adducts including [M+H]+, [M+Na]+, [M+NH4]+, [2M+NH4]+, [2M+Na]+ and [2M+H]+ in positive ion mode, and 8 adducts including [M-H]-, [2M-H]-, [M+Cl]-, [M+FA-H]-, [3M-H]-, [M+Na-2H]-, [M-H2O-H]- and [M+TFA-H]- in negative ion mode, while 1 to 6 adducts were observed in the mass spectrum of a single standard, and each metabolite standard had a dominant adduct of a preference for ESI mode. Melibose was suitable for ESI positive ion mode detection, gossypol was suitable for both ion modes detection; and 12 compounds were suitable for negative ion mode detection due to mass spectrum signals of their dominant adduct stronger in negative ion mode than positive ion mode. [Conclusion] Based on the accurate molecular weight, the established identifying method can identify the 18 cotton metabolite standards with their nontarget mass spectrometry data. Under the determined UPLC and ESI condition, the dominant adducts of cotton secondary metabolites have the preference of ESI mode. These results provide technical and theoretical data support for further study of cotton metabolomics. 相似文献
2.
RNA干扰及其植物抗病毒应用 总被引：3，自引：0，他引：3
【研究目的】RNA干扰(RNA interference,RNAi)是分子生物学研究领域的一项新兴技术,在动植物的遗传改良、功能基因组、基因治疗等研究中广泛应用;【方法】它是指一些小的双链RNA分子介导的、序列特异的转录后基因沉默现象;【结果】本文就RNA干扰的作用机制、RNA干扰与植物病毒间的互作以及RNA干扰表达载体构建的一些研究进展进行了综述;【结论】随着RNAi研究的进一步深入,RNAi必将成为遗传育种工作者培育抗病毒植物的有力手段,促进植物抗病育种的发展。 相似文献
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血红蛋白存在于动物、植物、细菌、真菌、酵母、藻类、原生动物等生物体中。利用PCR方法克隆了蓝细菌Synechocystis sp. PCC 680的血红蛋白基因SLR2097,该基因属于“truncated”血红蛋白家族,大小为375 bp,编码123个氨基酸残基。数据库搜索的结果显示所有的血红蛋白都有一个保守基序,即‘F-[L]-x(4)-[G]-G-[T]-x(2)-[Y]-x-[G]-[R]-x-[M]-x(3)-H’, “truncated”血红蛋白家族也有该结构,表明它们的进化祖先相同。将获得的SLR2097连接到双元载体pCAMBIA1300-CaMV35S上,并转化甘蓝型油菜品种宁油12。转基因油菜表型分析表明,血红蛋白基因SLR2097在油菜中的表达促进油菜的生长并缩短发育期,引起早熟,这些表型对改良油菜的农艺性状有重要的应用价值。 相似文献
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摘要 [目的]为东兰县退耕还林的后续管理提供理论依据;[方法]采用查阅资料和典型抽样的样地调查方法,调查了东兰县的自然环境条件、社会环境条件、林业生产条件和土地资源条件;[结果]东兰县的环境条件适合退耕还林工程的实施;[结论]东兰县实施退耕还林的适宜树种主要有：板栗、八角和喜树三种。 相似文献
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GC-MS法检测广藿香挥发油的化学成分 总被引：1，自引：0，他引：1
摘要 [目的] 建立广藿香挥发油的指纹图谱检测方法,对广藿香的品质进行控制。[方法] 采用GC-MS法对广藿香挥发油成分进行定性和量化分析,并对市售的不同批次样品进行检测。[结果] 以9个共有峰为评价指标,实验的重复性、稳定性、重现性良好;不同批次的样品各组分的含量有显著差异。[结论] 以9个共有峰作为广藿香挥发油的指纹图谱,以广藿香酮与广藿香醇的峰面积比值作为控制质量的指标参数,建立了相应的指纹图谱。建议在使用广藿香时应根据产品的不同特点建立相应的指纹图谱质量标准。 相似文献
6.
滤纸片法筛选不同活性物对棉花黄萎病菌抑制效果研究 总被引：7，自引：1，他引：6
[ 目的] 为了筛选对棉花黄萎病菌有效的活性物。[ 方法] 采用滤纸片测定了52种活性物对棉花黄萎病菌的抑制效果。试验结果的记载由分级记载法表示、直观图片表示和160倍显微图片表示。[ 结果] 结果表明,本研究筛选出了14种对棉花黄萎病菌抑制效果显著的活性物。[ 结论] 该研究为筛选对棉花黄萎病菌高效活性物及田间防治棉花黄萎病提供理论依据。 相似文献
7.
A. Ashri 《Euphytica》1976,25(1):777-785
Summary The plasmon constitution of 68 different accessions of cultivated peanuts (Arachis hypogaea L.) was studied in crosses with one or another of three testers: V4, VSM and HG1, having the [V4], [O] and [G] plasmons, respectively. The plasmons interact differently with three plasmon-sensitive nuclear genes, thereby determining whether the plants will be erect or trailing. From the phenotypes of the reciprocal F1 hybrids it was concluded that the [G] plasmon of HG1 is rare-it is present in this cultivar and possibly in a few other; the [V4] plasmon is rare, being present in the V4 cultivar and possibly in a few other accessions; the [O] plasmon is widespread, being present in lines from various geographical origins and in at least three of the four botanical types of cultivated peanuts. 相似文献
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为制定三唑酮在食用菌上的残留安全标准,在吉林农业大学食用菌基地进行栽培培养,采用子实体喷药、培养料拌药的方法进行残留动态试验,通过气相色谱-质谱联用仪测定分析三唑酮在子实体和培养料中的残留量和残留动态。结果表明,三唑酮在食用菌及培养料中的降解过程均符合一级动力学方程,三唑酮在食用菌和培养料的半衰期分别为2.3~3.1天和14.2天。平菇、榆黄蘑及其培养料在收获时期的三唑酮残留量均小于0.01 mg/kg。证明试验建立的检测方法准确可靠,并为在食用菌上制定的MRL值提供了科学依据。 相似文献
9.
[Objectives]The research aimed to optimize the extraction method of triterpenoids from A. selengnesis. [Methods]The ultrasonic extraction of triterpenoids in A.... 相似文献
10.
Can additional N fertiliser ameliorate the elevated CO2‐induced depression in grain and tissue N concentrations of wheat on a high soil N background? 
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下载免费PDF全文 M. Tausz R. M. Norton S. Tausz‐Posch M. Löw S. Seneweera G. O'Leary R. Armstrong G. J. Fitzgerald 《Journal of Agronomy and Crop Science》2017,203(6):574-583
Elevated CO2 stimulates crop yields but leads to lower tissue and grain nitrogen concentrations [N], raising concerns about grain quality in cereals. To test whether N fertiliser application above optimum growth requirements can alleviate the decline in tissue [N], wheat was grown in a Free Air CO2 Enrichment facility in a low‐rainfall cropping system on high soil N. Crops were grown with and without addition of 50–60 kg N/ha in 12 growing environments created by supplemental irrigation and two sowing dates over 3 years. Elevated CO2 increased yield and biomass (on average by 25%) and decreased biomass [N] (3%–9%) and grain [N] (5%). Nitrogen uptake was greater (20%) in crops grown under elevated CO2. Additional N supply had no effect on yield and biomass, confirming high soil N. Small increases in [N] with N addition were insufficient to offset declines in grain [N] under elevated CO2. Instead, N application increased the [N] in straw and decreased N harvest index. The results suggest that conventional addition of N does not mitigate grain [N] depression under elevated CO2, and lend support to hypotheses that link decreases in crop [N] with biochemical limitations rather than N supply. 相似文献
11.
[Objectives] To determine the optimum extraction technology for total phenols of leaves in Acanthopanax giraldii Harms.[Methods]The single factor test and ortho... 相似文献
12.
Summary Genetic variability in the apple [Malus] fruit disorder bitter pit and fruit calcium concentrations ([Ca]) was determined in 25 seedling families at each of two sites from 1999 to 2000 and again for one site, in 2001. Most trees were free of pit or had low pit incidence, which could be approximated by an over-dispersed binomial distribution. A genetic component to external and internal pit incidence was found across both sites and all years. This effect was irrespective of the use of several cropping factors, average fruit weight or fruit mineral concentrations as covariates in the analyses. Year and/or site always had substantial effects on pit incidence. Interactions of genetic effects with site or year were also detected with large differences in mean pit incidence between sites or years for some families but not others. No relationship was found between mean family pit incidence and mean family [Ca] or mean family harvest date. However fruit [Ca] and harvest date were usually important predictors of within-family variation in pit incidence. For any one seedling, family had the largest effect on bitter pit incidence followed by site and [Ca] and the smallest effect was that of harvest date. [Ca] showed a strong genetic component and estimated family means of [Ca] were consistent at different sites and years. These results suggest that susceptibility of apple genotypes to bitter pit in breeding programmes may be best assessed through screening across multiple sites and seasons. Fruit [Ca] might be useful as an indirect selection index for bitter pit within, but not among families. 相似文献
13.
《Medicinal Plant》2014,(1)
[Objective]To explore the methods for extraction and content determination of polysaccharides from Hedysayum polybotrys Hand.-Mazz.,and to observe its anti-inflammatory effect. [Methods] Polysaccharides were extracted by hot water. The content determination was performed at wavelength 490 nm with phenol-sulfuric acid as a chromomeric agent. [Results]The content of HPS was 4. 94% in same batch of radix hedysari slices,while that reached 45. 30% in refined radix hedysari samples. HPS inhibited the xylene-induced ear swelling in mice.[Conclusions]The phenol-sulfuric acid method is simple,rapid,and accurate,and HPS has anti-inflammatory effect. 相似文献
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[Objectives]This study aimed to establish a method for determination of adulteration dye auramine O in Gegen Qinlian tablets by HPLC-MS/MS.[Methods]The instrume... 相似文献
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【目的】荧光原位杂交技术可以实现DNA序列直观准确的染色体定位,是基因组深入研究的重要技术之一。染色体特异探针的获得是该技术应用的关键。本研究旨在建立棉花寡核苷酸荧光原位杂交技术。【方法】利用已经公布棉花基因组序列数据,采用生物信息学方法获得染色体特异的寡核苷酸库,随后用乳化聚合酶链式反应方法标记成荧光探针,在棉花有丝分裂中期染色体上进行原位杂交。【结果】建立了一套棉花寡核苷酸荧光原位杂交技术体系。【结论】该体系可用于棉花单染色体识别鉴定。 相似文献
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[Objectives]To establish a method for determining the naringin content in the peel of Guangxi Citrus maxima(Burm.)Merr.[Methods]The high performance liquid chro... 相似文献
18.
《Medicinal Plant》2014,(Z1)
[Objective] To detect the methoxybenzyl alcohol content in brain tissue and cerebrospinal fluid of rats by HPLC.[Methods]Contents of methoxybenzyl alcohol in normal rats and MCAO rats were detected by HPLC.[Results]The standard curves of methoxybenzyl alcohol in brain tissue and cerebrospinal fluid were y = 0.1192 x- 0.0635( R2= 0.9998) and y = 0.1822 x + 0.0157( R2= 0.9999),respectively,showing good linear relationship.The within-day and between-day RSD values and absolute recovery rate were all within the defined limits.[Conclusions] This method was simple and accurate,and could be used for the content detection of methoxybenzyl alcohol in brain tissue and cerebrospinal fluid. 相似文献
19.
《Medicinal Plant》2014,(5)
[Objective] To establish a content detection method for the total flavonoids in Melastom adodecandnun Lour. [Methods]Content of total flavonoids in M. adodecandnun was detected by UV-Vis spectrophotometry. [Results]When the content of total flavonoids in M. adodecandnun was detected by UV-Vis spectrophotometry,there was good linear relationship(r = 0. 999 6) within the range of 0. 004 16- 0. 066 59mg/mL. The average recovery rate was 98. 85% and RSD was 2. 75%. [Conclusions]This method was accurate,simple and could be used for the content detection of total flavonoids in M. adodecandnun. 相似文献
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[Objectives] To study on colorimetric method and content determination of total phenol in homemade plum wine. [Methods]The optimal determination condition of to... 相似文献