甜菜DAMD-PCR体系的建立及优化

为了建立甜菜DAMD扩增体系,以期利用DAMD引物应用于甜菜品种指纹图谱的构建及分子标记辅助育种。本实验利用单因素变量的方法对甜菜DAMD体系进行优化。同时选用12个甜菜品种,利用优化的体系对25条DAMD引物进行扩增。获得甜菜的最适DAMD体系:总体积为20μL,包含模板DNA 10~80 ng、0.75 U的DNA聚合酶、0.2μL的d NTPs(2.5 mmol/L each)以及2.0μL的引物(10μmol/L)。同时25条引物均扩增出了清晰条带,除了个别引物多态性较差外,其余引物多态性都非常的丰富,其中引物62H(-)就可以把实验中用到的12个甜菜品种全部区分开。由此可见,DAMD引物的扩增效率很高,并且扩增结果稳定,条带清晰,非常适合甜菜品种指纹图谱的构建及遗传多样性分析。     

橄榄SRAP-PCR体系的建立和优化

以橄榄品种为材料,采用L16（45）的正交试验设计,对影响PCR反应的Taq酶量、Mg2+浓度、模板DNA含量、dNTPs浓度和引物浓度5个因素进行了SRAP-PCR扩增反应条件优化研究,并利用反应体系对11个橄榄品种进行了SRAP-PCR扩增。结果表明：在20μl体系中,Taq酶1.5U、Mg2+2.5 mmol/L、模板DNA 60ng、dNTPs 0.2 mmol/L和引物0.15μmol/L时的扩增效果最好;利用该体系,SRAP标记引物对Me5- Em2在11个橄榄品种中可以扩增出7条清晰的多态性条带。     

砂仁及其混伪品益智仁的ISSR分子鉴别

为创建砂仁及其主要混伪品益智仁的ISSR分子鉴别方法,以UBC818为引物,对影响ISSR-PCR反应体系的引物、dNTPs、DNA模板、Taq DNA聚合酶和Mg2+浓度进行5因素4水平正交优化试验,并在此基础上筛选阳春砂ISSR引物及砂仁正伪品的鉴别引物。结果表明,20μL阳春砂ISSR-PCR最佳反应体系包括引物0.5μmol/L、dNTPs 0.25 mmol/L、DNA模板40 ng、Taq DNA聚合酶1.2 U、Mg^2+2.0 mmol/L;从52条ISSR引物中筛选出10条阳春砂ISSR引物,从6条阳春砂和益智的共同引物中,筛选出扩增条带清晰、多态性强的砂仁正伪品的鉴别引物UBC808,利用UBC808对15份样品进行验证试验,结果表明鉴别体系稳定性好,可用于砂仁与益智仁的快速、准确鉴别。     

牡丹杂交品系SRAP-PCR反应体系优化及引物筛选

通过研究牡丹杂交新品系的遗传多样性,解决其在牡丹品种分类体系中位置的问题。利用正交设计,从Mg2+、dNTPs、引物浓度、DNA聚合酶和不同模板DNA浓度5种因素4个水平来优化牡丹杂交品系SRAP-PCR反应体系,对引物进行筛选。建立牡丹杂交品系SRAP-PCR反应最佳体系(25 μL)为： 2.0 mmol/L Mg2+、1.5 U Taq酶、0.25 mmol/L dNTPs、2 ng/μL模板DNA、0.25 μmol/L引物;运用试验结果从100对引物中筛选出扩增条带清晰、多态性丰富的SRAP引物30对。优化体系的建立及引物的筛选,可为利用SRAP标记技术研究牡丹杂交品系的遗传多样性及亲缘关系提供技术基础和理论依据。     

红毛丹SRAP反应体系优化及多态性标记筛选

为建立成熟可靠的红毛丹SRAP-PCR扩增检测技术体系,本研究首先采用单因素实验设计,对反应体系中的DNA模板、Mg2+、d NTPs、Taq DNA聚合酶和引物浓度等5个主要影响因素,设置不同的水平梯度,筛选出适宜的因子范围;在此基础上,进一步采用L16(45)正交设计,建立了红毛丹SRAP-PCR最佳反应体系:20μL体系中包含DNA模板20 ng、d NTPs 0.25 mmol/L、引物0.6μmol/L、r Taq酶1.0 U、Mg2+2.5 mmol/L。并利用优化的反应体系,从116对SRAP引物组合中筛选出37对扩增条带清晰、产物多态性较好的引物。本研究建立的SRAP-PCR体系及筛选的引物,将为红毛丹从分子水平进行种质资源遗传多样性分析、品种指纹图谱构建等研究提供基础。     

金银花ISSR-PCR反应体系的建立与优化

以金银花叶片基因组DNA为模板,通过单因素试验,研究了退火温度、Taq DNA 聚合酶的用量及模板DNA、引物、dNTPs、Mg2+浓度等6种因素对ISSR－PCR扩增的影响,建立了适合于金银花ISSR-PCR反应体系和扩增程序,即在20 μL反应体系中,内含1×PCR反应缓冲液（Mg2＋free）、1.5 U Taq DNA 聚合酶、0.15 mmol·L-1 dNTPs、0.4 μmol·L-1引物、1.5 mmol·L-1 MgCl2、60 ng模板DNA。确定了适宜的退火温度为49.9 ℃。扩增程序为94 ℃预变性5 min ;35个循环为94 ℃变性30 s,49.9 ℃退火30 s,72 ℃延伸1.5 min;最后72 ℃延伸7 min,4 ℃保存。利用优化反应体系,从100条ISSR引物中筛选出10条稳定性和重复性高的引物;以这10条引物对22个金银花品种基因组DNA扩增,共扩增出108条带,其中多态性条带96条,多态性条带比率为88.9%。金银花ISSR反应体系的建立为利用ISSR标记技术进行金银花品种鉴别、分类、种质资源遗传多样性分析奠定了良好基础。     

正交设计优化青蒿SRAP-PCR反应体系及引物筛选

为了建立青蒿的SRAP最佳扩增体系,并筛选出SRAP多态性引物,本研究以青蒿叶片DNA为模板,采用正交试验设计,以Mg^2+、dNTP Mix、Taq DNA聚合酶、引物和DNA模板5种因素5个水平,对青蒿SRAP反应体系进行研究。结果表明,青蒿SRAP-PCR最佳反应体系为:引物0.6μmol/L、Mg^2+2.0 mmol/L、模板DNA 5.1 ng、Taq DNA聚合酶2.0 U、dNTPs 0.25 mmol/L,总体积为25μL。各因素对扩增反应均有不同影响,其中引物浓度的影响最大,dNTPs的影响最小。运用该体系对不同种质资源的青蒿进行验证,证明该体系稳定可靠,并在30个引物组合中筛选出了25对扩增条带清晰,多态性丰富的引物组合。这一结论为今后利用SRAP标记技术进行青蒿分子遗传学研究提供了科学依据。     

二月兰SSR-PCR反应体系的优化及引物筛选

为建立适合二月兰的SSR-PCR反应体系,采用正交试验设计方法对影响二月兰SSR反应体系的5个因素(DNA模板、Mg~(2+)、d NTPs、引物和Taq聚合酶)进行优化试验,筛选出每个因素的最佳水平。结果表明,10μL反应体系中,Mg~(2+)浓度2.0 mmol/L,d NTPs浓度0.4 mmol/L,引物浓度0.6μmol/L,DNA模板量20 ng,Taq聚合酶量0.6 U。以3份二月兰基因组DNA为模板,利用优化后的SSR-PCR反应体系进行引物筛选,从50对SSR引物中成功筛选出扩增条带清晰、具有多态性的引物有12对,证明该反应体系具有较好的稳定性和通用性。研究建立和优化的二月兰SSR-PCR反应体系,为进一步利用SSR标记技术开展二月兰分子生物学研究提供了理论依据和技术参考。     

药用菊花SSR-PCR反应体系优化及引物筛选

为进一步开发利用药用菊花种质资源和开展分子标记辅助选择育种,本研究利用L25(56)正交设计对影响药用菊花SSR-PCR反应的模板DNA、Mg2+、d NTPs、Taq酶、引物等5个因素进行优化,并对SSR引物进行筛选。结果建立了药用菊花SSR-PCR最佳反应体系(20μL):模板DNA 60 ng,正、反向引物0.25μmol/L,d NTPs 0.3 mmol/L,Mg2+3.0 mmol/L,Taq酶1.5 U。运用优化后的反应体系,从136对引物中成功筛选出了扩增条带清晰、多态性丰富的SSR引物57对,大多数条带大小集中在100~500 bp,不同引物扩增的条带数为5~15条。优化的SSR-PCR反应体系在多个药用菊花品种遗传多样性研究中得到了验证,获得了稳定性、重复性良好和多态性丰富的扩增图谱。该体系的建立可为今后利用SSR标记对药用菊花种质鉴定、遗传多样性分析、系统发育研究、遗传图谱构建、基因定位和分子标记辅助育种等研究提供了依据。     

茶花品种SSR指纹图谱分型技术反应体系优化

建立茶花品种分子指纹图谱对茶花品种鉴别、品种选育和深入实施品种产权保护等具有重要意义。为筛选适用于茶花品种SSR指纹图谱构建的引物及其最优反应体系,采用梯度退火温度和正交试验设计的方法,对4对SSR引物反应条件进行了研究。结果表明,2对引物扩增出目的条带,其中引物MSCjaF25最适退火温度52.9℃,10 mL体系中各组分含量为Mg²⁺ 1.2 mmol/L、dNTPs 0.2 mmol/L、Taq DNA聚合酶0.5 U、引物0.2 mmol/L以及模板DNA 40 ng时图谱质量最优;引物MSCjaF37最适退火温度58.2℃,10 mL体系中各组分含量为Mg²⁺ 0.8 mmol/L、dNTPs 0.1 mmol/L、Taq DNA聚合酶1.0 U、引物0.3 mmol/L以及模板DNA 40 ng时,图谱质量最优。以12个茶花品种进行扩大试验证明,优化的体系重复性和稳定性良好。研究为茶花品种分子指纹图谱的构建奠定重要基础。进一步分析显示,全面开展茶花品种分子指纹图谱研究还面临着筛选更多通用SSR引物的挑战。     

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.     

A note on the origin of Kalanchoë x vadensis Boom & Zeilinga (Crassulaceae)

Summary K x vadensis is a hybrid of K. blossfeldiana and K. marmorata obtained after doubling the number of chromosomes.     

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...     

Avoidance of leaf rust fungi in wild relatives of cultivated cereals

Summary Avoidance of rust fungi that was based on poor appressorium induction was previously found in Hordeum chilense. In the present study 95 accessions of Triticeae were screened for avoidance of Puccinia hordei. The percentage of appressorium formation per germinated spore ranged from 6 to 90%. On none of the 41 accessions of Aegilops, Agropyron, Elymus, Secale, Thinopyrum or Triticum studied was the rate of appressorium formation lower than 25%. Lower rates of appressorium formation were, however, found on accessions of wild barley species Hordeum brachyantherum, H. marinum, H. parodii and H. secalinum. Its implications in cereal breeding are discussed.     

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.     

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...     

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).     

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...     

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.     

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.