血红鸡爪槭叶片总RNA提取方法的比较研究

血红鸡爪槭叶片中富含多糖、多酚物质,严重影响了RNA提取纯度和质量。为了获得适宜血红鸡爪槭叶片总RNA提取的方法,采用柱式植物RNAout法、TRIZOL法和改良CTAB法3种提取方法对其叶片总RNA提取效果进行比较分析。结果显示,采用柱子法提取获得的总RNA产率最高,但是有DNA污染;TRIZOL法提取的总RNA OD260∕OD280为1.65,可能有多糖和酚类物质的污染,并且产率最低;改良CTAB法提取的总RNA纯度很高,OD260/OD280平均值在2.0左右,产率在上述两种方法之间,电泳图清晰,而且改良CTAB法提取的总RNA,经RT-PCR获得了清晰的特异性条带。表明改良CTAB法提取的总RNA纯度和产率高,完全可以满足进一步分子生物学研究的需要,是血红鸡爪槭叶片总RNA提取的适宜方法。     

魔芋叶片中4种总RNA提取方法的比较

本研究分别利用TRIzol法、异硫氰酸胍法、改良的CTAB法及试剂盒这4种方法提取魔芋叶片的总RNA,并用紫外光谱和琼脂糖凝胶电泳对各个提取效果进行鉴定。反复试验的结果表明:TRIzol法难以提取魔芋叶片总RNA,异硫氰酸胍法提取的总RNA浓度低、杂质较多且有部分降解,这两种方法不适宜用于魔芋叶片总RNA提取;试剂盒方法提取的总RNA产率和纯度较高,但稳定性差、成功率低且成本较高;改良的CTAB法利用PVP和β-巯基乙醇去除酚类物质,水饱和酚-氯仿去除蛋白质,醋酸钾去除多糖,该方法提取得到的总RNA的纯度较高,OD260/OD280值为1.893,而且效果稳定,有良好的可重复性。因此,我们认为改良的CTAB法是一种简便、快速且经济的提取魔芋叶片总RNA的方法。     

银杏叶片RNA提取方法的研究

为了获得一种银杏（Ginkgo biloba L.）叶片总RNA提取的理想方法,为后续的分子生物学研究打下基础,笔者以不同生长期的叶片为材料,利用生物分光光度计和凝胶电泳法比较了改良CTAB法、乙二醇丁醚法以及改良Trizol法提取的银杏总RNA的产率和纯度。结果表明：改良Trizol法所提取RNA的OD260/OD280比值介于1.8~2.0之间,并且OD260/OD230在1.9~2.1之间,具有较高的纯度。凝胶电泳结果表明,改良Trizol法有28S rRNA和18S rRNA 2条清晰的条带,且很少有降解;CTAB法获得的RNA品质也较好,但存在降解和弥散现象,乙二醇丁醚法提取效果较差。这表明改良Trizol法提取的总RNA具有很高的纯度,可以满足进一步分子生物学研究的要求。     

野生香蕉叶片总RNA提取方法研究

采用TRIZOL试剂盒法、RNAsio试剂法和改良CTAB法提取香蕉叶片总RNA,并通过凝胶电泳、紫外分光光度法检测提取的RNA样品的质量。研究结果表明：改良CTAB法提取的RNA具有28SrRNA和18SrRNA两条清晰的条带,OD260／OD280在1.80-1.95之间,OD260／OD230在1.75-2.10之间,具有较高的纯度;其它两种方法获得的RNA纯度不够,降解严重。将提取的RNA分别逆转录成cDNA,经RT-PCR扩增,只有改良CTAB法出现清晰的条带,进一步证明改良CTAB法提取的RNA具有很高的纯度,可以满足进一步分子生物学研究的要求。     

适宜苹果组培苗总RNA提取方法的研究

利用CTAB_异硫氰酸胍法、改良CTAB法和RNAplant试剂盒法,从富含多糖和酚类物质的苹果组培苗继代苗中提取总RNA。结果表明CTAB_异硫氰酸胍法对苹果组培苗总RNA的提取有较好的效果,所得RNA的A260/A230大于2.0,A260/A280为1.8~2.0,产率在16.95μg/g左右。改良CTAB法和RNAplant试剂盒法提取的RNA均有少量DNA污染,但RNAplant试剂盒法比CTAB法更快捷,简便。     

草莓果实总RNA提取方法的比较

为建立草莓果实总RNA的提取方法,针对草莓成熟果实中富含多糖、多酚和色素等次级代谢物质,总RNA提取难度大的特点,比较改良的EASYspin 植物RNA提取试剂盒法和改良的CTAB法提取草莓果实中总RNA的质量。通过琼脂糖凝胶电泳和核酸蛋白测定仪(NanoDrop 2000)检测2 种方法提取总RNA的浓度、纯度及完整性等。改良的EASYspin 植物RNA提取试剂盒法和改良的CTAB法都能够完成草莓果实总RNA 的提取,电泳检测在28S 和18S 处呈2 条清晰的条带,OD260/OD280值和OD260/OD230值均在2.0 左右;改良的EASYspin 植物RNA提取试剂盒法成本较高,且提取总RNA质量劣于改良的CTAB法,但是EASYspin植物RNA提取试剂盒法操作简便,安全可靠,节省时间。通过RT-PCR验证,2种方法所获得的草莓果实总RNA质量较好,可达到分子生物学试验对RNA质量的要求。     

椰子果肉组织中总RNA的提取及质量分析

本研究以椰子(Cocos nucifera L.)果肉组织为材料,应用改良CTAB法对不同成熟度的椰肉组织总RNA进行提取分析.结果表明:改良CTAB法能有效去除椰肉组织中不同种类杂质的干扰,从两种不同成熟度的椰肉组织中获得了高质量的总RNA;应用琼脂糖凝胶电泳检测得到两条清晰的谱带,分别为28S和18S.通过紫外分光光度计检测含量和纯度显示:OD260/OD280值介于1.6～1.9之间,不同成熟度的椰肉组织提取的总RNA的浓度分别为0.070 μg/μL和0.053μg/μL.本研究使用的方法适用椰肉组织总RNA的提取,能够获得质量好、产率高、完整性强的总RNA,为进行椰子果实发育相关基因的克隆和分析奠定了一定的研究基础.     

适宜当归实时荧光定量分析的总RNA提取方法研究

为了有效消除次生物质、多糖和多酚类物质的严重干扰,获得高质量适宜于实时荧光定量分析的当归总RNA,本研究采用CTAB法、试剂盒法和Trizol法分别提取当归根、茎、叶组织的总RNA,并通过紫外可见光分光光度计、非变性琼脂糖凝胶电泳和反转录荧光定量PCR检测总RNA的纯度、产率、完整性及质量。结果表明：CTAB法提取的当归根、茎、叶组织总RNA纯度较高、完整性较好且叶组织总RNA得率较高;试剂盒法所提的总RNA完整性亦较好,但纯度略差且各组织的得率均较低;Trizol法提取的茎组织总RNA能满足荧光定量PCR要求,但提取的根和叶组织总RNA均出现严重污染,无法满足后续研究要求。因此,CTAB法是一种经济、可靠、适宜当归实时荧光定量分析的总RNA提取方法。本研究结果为今后有效开展当归分子生物学研究奠定了方法学基础,也为其他药用植物总RNA的提取提供了参考。     

水茄果实总RNA提取方法的比较分析

水茄果实中富含多糖、蛋白、色素和其他代谢物质,影响其总RNA提取的质量。本研究中比较Trizol法、改良Trizol法、改良CTAB法和两种试剂盒法5种方法提取的水茄果实总RNA,用琼脂糖凝胶电泳检测总RNA的完整性,Onedrop光谱仪检测总RNA的浓度和纯度。结果表明:改良Trizol法最为有效,该方法提取的总RNA在琼脂糖凝胶上得到清晰的28S和18S条带,OD_(260nm)/OD280nm值在1.8~2.1之间、OD_(260nm)/OD_(230nm)的比值大于2.0;改良CTAB法获得的RNA质量较好,但步骤较为繁琐,耗时长;Trizol法和试剂盒法得到总RNA浓度较低。RT-PCR试验进一步表明,以改良Trizol法获得的总RNA可用于基因分离,所得条带清晰,与目的片段大小一致且比对正确。     

三种改良提取长雄野生稻根叶总RNA方法的比较研究

为探讨野生稻总RNA的提取,笔者尝试了改良SDS、CTAB和TRIzol三种提取方法分别提取长雄野生稻根和叶总RNA,通过琼脂糖凝胶电泳和分光光度计检测,比较这三种方法的提取效果.结果表明,改良SDS、CTAB法提取的根总RNA的电泳条带清晰,几乎没有污染,无明显降解,OD260/OD280在1.75～2.0之间,能满足一般的分子操作要求,但所提取的叶片总RNA则有明显的DNA污染和少量的蛋白质污染.用TRJzol法提取的总RNA,无论是根还是叶片,均有不同程度蛋白质污染.若要进行下一步的分子操作,需先进行RNA的纯化,以去除蛋白质.可见改良SDS、CTAB法提取根的总RNA是首选.     

Biological Activity and Quantification of Suspected Allelochemicals from Alfalfa Plant Parts

Autotoxicity restricts reseeding of alfalfa (Medicago sativa L.) after alfalfa until autotoxic chemical(s) breaks down or is dispersed into external environments. A series of aqueous extracts from leaves, stems, roots and seeds of alfalfa ‘Vernal’ were bioassayed against alfalfa seedlings of the same cultivar to determine their autotoxicity. The highest inhibition was found in the extracts from the leaves. Extracts at 40 g dry tissue l^?1 from alfalfa leaves were 15.4, 17.5 and 28.7 times more toxic to alfalfa root growth than were those from roots, stems and seeds, respectively. A high‐performance liquid chromatography (HPLC) analysis with nine standard compounds showed that the concentrations and compositions of allelopathic compounds depended on the plant parts. In leaf extracts that showed the most inhibitory effect on root growth, the highest amounts of allelochemicals were detected. Among nine phenolic compounds assayed for their phytotoxicity on root growth of alfalfa, coumarin, trans‐cinnamic acid and o‐coumaric acid at 10^?3 m were most inhibitory. The type and amount of causative allelochemicals found in alfalfa plant parts were highly correlated with the results of the bioassay, indicating that the autotoxic effects of alfalfa plant parts significantly differed.     

Changes in Seed Yield and Quality with Maturity in Onion (Allium cepa L., cv. 'Early Cream Gold')

Development of onion (Allium cepa L., cv. ‘Early Cream Gold’) seed under cool climate conditions in Tasmania, Australia occurred over a longer duration than previously reported, but similar patterns of change in yield components were recorded. In contrast to previous studies, umbel moisture content declined from 85 to 67 % over 57 days while seed moisture content decreased from 85 to 31 %. Seed yield continued to increase over the duration of crop development, with increasing seed weight compensating for seed loss resulting from capsule dehiscence in the later stages of maturation. Germination percentage was high and did not vary significantly from 53 to 77 days after full bloom (DAF), but mean germination time declined and uniformity of germination increased significantly over the same time period. The percentage abnormal seedlings declined with later harvest date, resulting in highest seed quality at 77 DAF. The results of this study suggest that the decision to harvest cool climate onion seed crops before capsule dehiscence will result in a loss of potential seed yield and quality.     

Location of a high-lysine gene and the DDT-resistance gene on barley chromosome 7

Summary The high-lysine gene in Risø mutant 1508 conditions an increased lysine content in the endosperm via a changed protein composition, a decreased seed size, and several other characters of the seed. The designation lys3a, lys3b, and lys3c, is proposed for the allelic high-lysine genes in three Risø mutants, nos 1508, 18, and 19. Linkage studies with translocations locate the lys3 locus in the centromere region of chromosome 7. A linkage study involving the loci lys3 and ddt (resistance to DDT) together with the marker loci fs (fragile stem), s (short rachilla hairs), and r (smooth awn) show that the order of the five loci on chromosome 7 from the long to the short chromosome arm is r, s, fs, lys3, ddt. The distance from locus r to locus ddt is about 100 centimorgans.     

Simultaneous Determination of Four Phenolic Acids in Radix Salviae Miltiorrhizae Formula Granules by QAMS

[Objectives]This study aimed to establish a QAMS(quantitative analysis of multi-components by single-marker)method for simultaneous determination of four phenol...     

Water Extraction Process of Chinese Herbal Compound Man Gan Ning

[Objectives]To optimize the water extraction process of Chinese Herbal Compound Man Gan Ning and establish a method for its extraction and content determination...     

Present status and future strategy in breeding faba beans (Vicia Faba L.) for resistance to biotic and abiotic stresses

Progress is being made, mainly by ICARDA but also elsewhere, in breeding for resistance to Botrytis, AScochyta, Uromyces, and Orobanche; and some lines have resistance to more than one pathogen. The strategy is to extend multiple resistance but also to seek new and durable forms of resistance. Internationally coordinated programs are needed to maintain the momentum of this work.Tolerance of abiotic stresses leads to types suited to dry or cold environments rather than broad adaptability, but in this cross-pollinated species, the more hybrid vigor expressed by a cultivar, the more it is likely to tolerate various stresses.     

Pollen and pollination experiments. III. The viability of apple and pear pollen as affected by irradiation and storage

Summary Apple and pear pollen was irradiated with doses of 0, 50, 100, 250 and 500 krad (gamma rays) and stored at 4°C and 0–10% r.h. From the in-vitro germination percentages an average LD 50 dose of about 220 krad was estimated. For both irradiated and untreated pollen a close and corresponding lineair relationship existed between germination percentage and pollen tube growth.Irradiated pollen was much more sensitive to dry storage conditions than untreated pollen, resulting in less germination and more bursting. Apparently, irradiation caused the pollen cell membrane to lose its flexibility faster than normal. Rehydration of dry-stored, irradiated pollen in water-saturated air restored germination percentages up to their initial levels. The importance of this procedure in germination trials is stressed.     

Optimization of Extraction Technology and Determination of Content of Total Phenols of Leaves in Acanthopanax giraldii Harms

[Objectives] To determine the optimum extraction technology for total phenols of leaves in Acanthopanax giraldii Harms.[Methods]The single factor test and ortho...     

Cytoplasmic male sterility,resistance to gall mite and mildew,and season of leafing out in black currants

Summary Cytoplasmic male sterility (cms) is described in the F₁ hybrids Ribes × carrierei (R. glutinosum albidum × R. nigrum) and R. sanguineum × R. nigrum. In backcrosses to R. nigrum, progenies with R. glutinosum cytoplasm were either all male sterile, or segregated for full male fertility (F) and complete (S) and partial (I) male sterility. Ratios of F:I+S suggested that two linked genes controlled cms, F plants being dominant for one (Rf ₁) and recessive for the other (Rf ₂).Segregation for cms in relation to three linded genes, Ce (resistance to the gall mite, Cecidophyopsis ribes), Sph ₃(resistance to American gooseberry mildew, Sphaerotheca mors-uvae) and Lf ₁(one of two dominant additive genes controlling early season leafing out) indicated that Rf ₁and Rf ₂were in this linkage group. The gene order and approximate crossover values appeared to be: % MathType!MTEF!2!1!+-% feaafiart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn% hiov2DGi1BTfMBaeXafv3ySLgzGmvETj2BSbqef0uAJj3BZ9Mz0bYu% H52CGmvzYLMzaerbd9wDYLwzYbItLDharqqr1ngBPrgifHhDYfgasa% acOqpw0xe9v8qqaqFD0xXdHaVhbbf9v8qqaqFr0xc9pk0xbba9q8Wq% Ffea0-yr0RYxir-Jbba9q8aq0-yq-He9q8qqQ8frFve9Fve9Ff0dme% aabaqaciGacaGaamqadaabaeaafaaakeaacaWGdbGaamyzamaamaaa% baGaaiiiaiaacccacaGGWaGaaiOlaiaacgdacaGG0aGaaiiiaiaacc% caaaGaaiiiaiaacccacaGGGaGaamOuaiaadAgaliaaigdakmaamaaa% baGaaiiiaiaacccacaGGGaGaaiiiaiaaccdacaGGUaGaaiOmaiaacs% dacaGGGaGaaiiiaiaacccacaGGGaGaaiiiaaaacaWGsbGaamOzaSGa% aGOmaOWaaWaaaeaacaGGGaGaaiiiaiaacccacaGGGaGaaiiiaiaacc% cacaGGGaGaaiiiaiaacccaaaGaamitaiaadAgaliaaigdakmaamaaa% baGaaiiiaiaacccacaGGGaGaaiiiaiaacccacaGGGaGaaiiiaiaacc% cacaGGGaGaaiiiaiaacccacaGGGaaaaiaadofacaWGWbGaamiAaSGa% aG4maaaa!6E4D!\[Ce\underline { 0.14 } Rf1\underline { 0.24 } Rf2\underline { } Lf1\underline { } Sph3\]. Crossover values of 0.36 for Ce-Lf ₁, and 0.15 for Lf ₁-Sph ₃were estimated from the relative mean differences in season of leafing out between seedlings dominant and recessive for Ce and Sph ₃.It is suggested that competitive disadvantage of lf ₁-carrying gametes and/or zygotes at low temperatures may be implicated in the almost invariable deficit of plants dominant for the closely linked mildew resistance allele Sph ₃. Poor performance of lf ₁- (and possibly lf ₂-) carrying gametes and young zygotes during periods of low temperature at flowering might also account for the liability of some late season cultivars and selections to premature fruit drop (running off).     

Screening techniques and sources of resistance to parasitic angiosperms

Parasitic angiosperms cause great losses in many important crops under different climatic conditions and soil types. The most widespread and important parasitic angiosperms belong to the genera Orobanche, Striga, and Cuscuta. The most important economical hosts belong to the Poaceae, Asteraceae, Solanaceae, Cucurbitaceae, and Fabaceae. Although some resistant cultivars have been identified in several crops, great gaps exist in our knowledge of the parasites and the genetic basis of the resistance, as well as the availability of in vitro screening techniques. Screening techniques are based on reactions of the host root or foliage. In vitro or greenhouse screening methods based on the reaction of root and/or foliar tissues are usually superior to field screenings and can be used with many species. To utilize them in plant breeding, it is necessary to demonstrate a strong correlation between in vitro and field data. The correlation should be calculated for every environment in which selection is practiced. Using biochemical analysis as a screening technique has had limited success. The reason seems to be the complex host-parasite interactions which lead to germination, rhizotropism, infection, and growth of the parasite. Germination results from chemicals produced by the host. Resistance is only available in a small group of crops. Resistance has been found in cultivated, primitive and wild forms, depending on the specific host-parasite system. An additional problem is the existence of pathotypes in the parasites. Inheritance of host resistance is usually polygenic and its transfer is slow and tedious. Molecular techniques have yet to be used to locate resistance to parasitic angiosperms. While intensifying the search for genes that control resistance to specific parasitic angiosperms, the best strategy to screen for resistance is to improve the already existing in vitro or greenhouse screening techniques.