茄子开花相关基因SmFT的克隆和表达分析

在光周期途径中,FT基因是决定植物开花时间的重要基因。本研究利用同源克隆的方法从"YZ-14"紫茄品种中分离克隆得到了FT基因,命名为Sm FT。序列分析表明,Sm FT基因的c DNA全长691 bp,开放阅读框为528 bp,编码176个氨基酸,与同科作物马铃薯中FT基因序列的相似性高达92%,与番茄中FT基因序列的相似性也能达到91%。成熟蛋白等电点为5.20,分子量为43.79 k D,荧光定量检测结果表明,Sm FT基因在紫茄的根、茎、叶、花瓣、果皮和果肉中均有表达,但表达水平具有组织特异性,其中,Sm FT基因在茎、叶和花中表达量较高,这可能与FT发挥作用的位置有关。本研究可为深入研究茄子的光周期反应机制提供了理论基础。     

光周期途径成花关键基因GIGANTEA和CONSTANS的研究进展

GIGANTEA(GI)和CONSTANS(CO)在植物光周期开花诱导途径中起促进作用。GI和CO基因受生物钟调控,表达量在一天内呈规律性变化。在长日照条件下,GI和CO基因促进拟南芥开花,但在短日照条件下,对拟南芥开花时间的影响不大。GI是影响生物节律钟输出和植物进行正常生命活动的重要基因,编码一个核蛋白,GI正调控CO基因的表达。CO是编码一个B-box锌指蛋白,是监测日照长度的重要元件,并激活FT基因表达,诱导植物开花。本综述概括了近年来GI和CO基因的结构和功能,为GI和CO基因的深入研究提供参考。     

金柑开花关键基因FcFT1的克隆及表达分析

本研究以融安金柑为试材,采用同源克隆技术获得成花素基因Fc FT1全长序列,并对该基因的生物信息学和遗传进化关系进行了分析。利用q RT-PCR技术,分析了Fc FT1在花发育期间不同花器官、不同组织,以及日周期中Fc FT1在花、茎、叶的表达情况。结果表明:Fc FT1基因完整开放阅读框为531 bp,编码177个氨基酸。Fc FT1编码的蛋白具有单一而非常保守的PEBP结构域;蛋白质结构比较不稳定,为亲水蛋白。系统进化树表明Fc FT1与甜橙、温州蜜柑和枳壳中的FT同源基因亲缘关系最近。q RT-PCR结果显示,在花发育期,花药中Fc FT1表达量最高;日周期变化中,Fc FT1在花、茎、叶中的平均表达量差距不显著,表达较稳定。本研究结果为进一步揭示FT基因在金柑开花调控中的功能奠定了基础。     

筇竹QtKAT1基因的克隆与表达分析

为探究竹类植物K+调控机理及K+通道的系统,本研究以筇竹(Qiongzhuea tumidinoda)为试验材料,对筇竹QtKAT1基因分离克隆及表达分析.通过克隆获得筇竹QtKAT1基因,全长为3 124bp,含2 235 bp的最大开放阅读框,编码744个氨基酸.生物信息学分析表明QtKAT1基因预测编码蛋白分子质...     

紫云英AGL18(AGAMOUS-LIKE18)基因克隆及功能鉴定

紫云英(Astragalus sinicus)是重要的绿肥作物,选育花期适当的品种是重要的育种目标。AGL18是关键的开花抑制基因,为了探究紫云英AGL18基因的功能,本研究通过RACE技术成功克隆了紫云英AGL18基因,基因cDNA全长为957 bp,含有1个738 bp的开放阅读框,编码的蛋白质含有245个氨基酸。编码的氨基酸序列与大豆、蒺藜苜蓿、菜豆的同源蛋白相似性均在77%以上,具有较高的保守性。基因表达分析显示,紫云英AGL18基因在各器官中均有表达,表达量由高到低依次为花芽、花、叶、根、叶芽、茎、荚果。通过超表达AGL18基因拟南芥验证了该基因的功能,结果证明,超表达AGL18基因拟南芥株系的抽薹天数比野生型平均迟10.78 d,开花天数比野生型平均迟11.28 d。本研究为调控紫云英花期提供了科学依据。     

舒马栎CHLD基因克隆及其表达分析

叶绿素是植物绿叶的主要呈色物质,镁离子螯合酶是叶绿素生物合成途径中的一个关键酶,对叶片的呈色具有重要影响。本研究从舒马栎叶片中克隆了一个镁离子螯合酶ChlD亚基(CHLD)基因,该基因cDNA全长为2 851 bp,具有完整的开放阅读框,编码804个氨基酸,与其他植物序列具有较高的一致,故命名为QsCHLD。生物信息学分析显示,QsCHLD基因编码的蛋白无信号肽,具有1个跨膜结构域和多个磷酸化位点。基因表达水平检测结果表明,QsCHLD基因在舒马栎绿色叶片中的表达水平显著高于黄色叶片。这一结果为今后通过基因工程手段调控舒马栎叶片呈色提供了科学依据。     

莲瓣兰大雪素SEP1基因克隆和表达的研究

随着植物中越来越多的MADS-box基因被克隆出来,人们对经典的ABC模型进行了改进和完善,提出花发育的ABCDE模型,其中SEP1、SEP 2、SEP 3、SEP 4为E类基因,SEP1同源基因在花器官的形成过程中起至关重要的作用.本研究以莲瓣兰大雪素作为实验材料,用RACE方法快速地克隆全长cDNA,生物信息学分析全长cDNA为1047 bp,具有完整的开放阅读框(ORF)753 bp,编码250氨基酸的蛋白质,获得一个SEP1同源基因.通过基因表达在各个授粉前和授粉后3d的合蕊柱中.本研究为进一步对这个基因的功能研究奠定基础.     

竹叶花椒查尔酮合成酶基因克隆与表达

查尔酮合成酶(chalcone synthase, CHS)是植物次生代谢途径中的关键酶。本研究依据转录组数据设计特异性引物,采用RT-PCR方法成功地从竹叶花椒(Zanthoxylum armatum)中克隆得到一个全新的CHS基因的全长cDNA序列,命名为ZaCHS (NCBI登录号:MK953733)。序列分析结果表明,ZaCHS包含完整的cDNA开放阅读框(OFR),由1 173 bp组成,编码390个氨基酸。Blast比对结果显示该蛋白属于CHS家族蛋白;系统进化树结果显示竹叶花椒ZaCHS与芸香科植物甜橙、克里曼丁桔等的CHS亲缘关系较近。荧光定量PCR检测显示,ZaCHS在竹叶花椒中的表达量从高到低分别为:嫁接树的叶、嫁接树的茎、实生树的茎、实生树的叶。通过对竹叶花椒CHS基因进行克隆与分析,为后续深入研究竹叶花椒类黄酮代谢途径相关基因、CHS基因表达调控以及CHS基因家族进化提供帮助。     

海南粗榧GGPPs基因克隆与诱导表达分析

濒危植物海南粗榧富含多种抗癌活性次生代谢产物。为研究这些产物的生物代谢途径和表达调控,通过同源克隆和RACE技术获得了海南粗榧紫杉醇生物合成途径中通用前体牻牛儿基牻牛儿焦磷酸合成酶(GGPPs)基因全长并进行了生物信息学分析。该基因命名为CmGGPPs(GenBank登录号:JX971119),并进一步利用不同激发子诱导研究了该基因对不同逆境信号的响应情况。结果表明:海南粗榧GGPPs基因cDNA全长1694bp,包含一个1182bp的ORF框,编码393个氨基酸;预测该基因编码蛋白质分子量为42.91kD,其等电位为7.12。通过BLAST比对结果分析,海南粗榧GGPPs基因全长核苷酸序列与红豆杉科植物的同源性最高可达91%,氨基酸序列有89%的相似性。同时,GGPPs基因氨基酸序列同其他植物也有较高的同源性。用不同类型激发子处理发现,GGPPs在诱导后表达量均上升,但不同激发子诱导的基因表达强度和速率存在明显区别。     

浙贝母ACO基因克隆、表达及生物信息学分析

本研究利用RT-PCR和RACE技术克隆出浙贝母1-氨基环丙烷-1-羧酸氧化酶(1-aminocyclo-propane-1-carboxylateoxidase, ACO)基因全长,对该基因进行生物信息学分析,并以‘浙贝3号’浙贝母花败期根、茎、叶及幼苗期至成熟期鳞茎为材料,采用RT-qPCR测定ACO基因在浙贝母中的时空表达。成功克隆得到的序列全长1 185 bp,开放阅读框为951 bp,编码317个氨基酸;浙贝母ACO氨基酸序列与同属百合科的麝香百合相似性最高,为95.21%。浙贝母不同部位ACO基因表达量依次为茎>根>叶>鳞茎,在鳞茎发育过程中ACO基因表达量逐渐增高,并在成熟期达到最高,比幼苗期提高了193.2%。     

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.