百合种质资源ISSR标记研究的引物筛选

为筛选出适合于百合种质资源ISSR标记研究的有效引物,利用58个ISSR引物,对百合属的卷丹、川百合、西伯利亚和索邦进行PCR扩增,共筛选出11条多态性丰富、条带清晰且可重复性好的有效引物,11条引物在4个样品中共扩增出125条DNA带,其中108条为多态性带,占总扩增带数的86.4％,平均每个引物扩增出11.4条带.该研究结果为应用ISSR标记技术进行百合属植物遗传多样性分析和品种分子鉴别等研究奠定了基础.     

茄子ISSR和SSR分子标记的鉴定技术分析

以茄子为研究对象,初步建立起茄子的ISSR和SSR分子标记技术体系,包括DNA提取、退火温度、循环次数和引物筛选等。结果表明,ISSR分子标记体系中,从49条引物中筛选出3个条带清晰的引物对6个品种进行扩增,共检测出26条带,其中多态性带21条,多态性比例为80.77%;SSR分子标记体系中,从4对引物中筛选出3个条带清晰的引物对6个品种进行扩增,共检测出17条带,其中多态性带5条,多态性比例为29.41%,2种方法均能把6个茄子品种区分开来,本实验为茄子品种鉴定和新品种选育提供理论依据。     

东方百合试管苗ISSR-PCR体系优化及引物筛选

为了对东方百合杂交育种获得的大量杂种后代进行分子标记早期鉴定,本研究采用单因素试验方法对模板DNA、Mg2+、Taq DNA聚合酶、d NTPs、引物等因子设置不同浓度梯度,建立了东方百合试管苗叶片ISSR-PCR最佳反应体系。反应体系为20μL,内含1×PCR Buffer、模板DNA 20 ng、Mg2+2.0 mmol/L、Taq DNA聚合酶0.7 U、d NTPs 0.3 mmol/L、引物0.4μmol/L。PCR扩增程序采用Touchdown-PCR程序。利用优化后的体系对46条ISSR引物进行筛选,最终筛出3A37、3A61、UBC840、UBC841、UBC844等5条多态性高,重复性好的引物,且引物序列以二核苷酸重复序列为主。本研究可为利用ISSR分子标记开展东方百合杂种真实性鉴定提供技术方法和支持。     

25个猕猴桃材料遗传多样性分析及DNA指纹图谱的建立

利用ISSR分子标记对25个猕猴桃品种和种质资源材料进行遗传多样性分析,并构建其ISSR指纹图谱,旨在阐明其亲缘关系,为遗传、育种和利用提供理论依据。结果显示,从100条引物中筛选出10条引物,在25个供试材料中共扩增出172条带,每条引物平均扩增条带数为17.2条,多态性条带169条,每条引物平均扩增多态性条带数为16.9条,多态性比例为98.26%;遗传相似系数值在0.51~0.87之间;在相似系数水平为0.604时,可将所有供试材料聚为三类。本研究构建的指纹图谱可用于猕猴桃种质的分类与鉴定,为种质资源的鉴定、分类、利用和杂交育种亲本的选配等方面提供理论依据。     

菠萝17份种质的ISSR分析

利用ISSR分子标记技术对17份菠萝种质进行了基因组DNA多态性分析。从62个ISSR引物中筛选出6个多态性引物用于PCR扩增，共扩增出70条DNA条带，其中多态性条带44条，所占比例为62.86%，平均每个引物扩增的DNA条带的数目为11.67条。6个品种具有特异性的扩增带，可作为种质鉴定的依据。根据ISSR扩增结果建立的UPGMA聚类图，在距离系数约0.1处可把供试的17份菠萝种质分为3大类。同时对供试品种的遗传关系进行了探讨     

菜心ISSR分子标记技术初步研究

以菜心为研究对象,初步建立起菜心的ISSR分子标记技术体系,包括DNA提取、退火温度、循环次数和引物筛选等.对退火温度进行优化,确定最佳退火温度为48℃,最优循环次数为45次.共筛选了49条引物,其中11条引物能扩增出多态性带,选择4个条带清晰的引物对6个品种进行扩增,共检测出32条带,其中多态性带为22条,多态性比例为68.80%,6个品种的遗传相似性系数为0.19～0.77.说明ISSR标记能够揭示材料间较高的遗传多样性,本试验为菜心的种子纯度鉴定和新品种选育提供理论依据.     

杂交水稻种子纯度分子鉴定技术研究

为了鉴定杂交水稻种子的纯度,用49条ISSR引物对供试的5组三系杂交水稻F1和父母本进行扩增,结果28条引物能扩增出DNA带,随机选取其中3条引物用于指纹分析,3条ISSR引物共扩增出32条DNA带,其中多态性条带为27条,并将这些多态性条带进行聚类分析。     

高羊茅杂交后代ISSR遗传变异研究

利用ISSR分子标记对高羊茅(Festuca arundinacea)杂交后代进行遗传多样性及亲缘关系分析.19个ISSR引物共扩增出255条重复性好、清晰的条带,其中200条是多态条带,多态条带比率(PPL)为78.4％,平均每个引物扩增多态条带数为10.5条,扩增片段大小范围为100～2 000 bp.结果表明,高羊茅杂交后代的多态性较高,遗传多样性较丰富.高羊茅杂交后代遗传相似性系数为0.647 1～0.851 0,聚类分析将高羊茅杂交后代划分为4个大类,有相同亲本的杂交后代先聚类.总之,ISSR标记可以有效地对高羊茅杂交后代进行“亲缘跟踪”和定向选择,为杂交育种提供分子依据.     

蓖麻种质资源多样性AP-PCR与RMAPD分析

为了研究国内主要商业蓖麻品种的种质资源多样性,采用AP-PCR与RMAPD分子标记方法,对来自国内不同地区的31份蓖麻品种进行分析。AP-PCR分子标记的研究结果表明,9条引物扩增的条带为5~12条,共计82条带,平均每条引物扩增出9.1条带,扩增的多态性条带为2~10条,多态率为40%~90.91%,共计53条带,平均每条引物扩增出5.89条多态性带。在9条引物中,引物S3扩增出多态性条带最高,多态率达90.91%。蓖麻种质资源的RMAPD分析结果表明,84对引物扩增的条带为5~12条,共计85条带,平均每对引物扩增出8.5条带,扩增的多态性条带为3~10条,共计56条带,平均每条引物扩增出5.6条多态性带。在84对引物中,引物A3+B4扩增出的条带最多,多态性最高,多态率达83.3%。对AP-PCR与RMAPD分子标记的数据进行联合聚类分析表明,在遗传系数为0.56处,31份蓖麻种质被分成3大类群。2种分子标记之间的相关系数不显著(R=0.009 3)。     

运用SRAP分子标记鉴定辣椒杂交种纯度

摘要：以辣椒品种航椒4号和航椒5号及其亲本H09-4、H09-2、WS-3、B-2-2为试验材料,运用SRAP分子标记技术研究了辣椒杂种与其亲本之间 扩增条带的多态性,鉴定和分析了航椒4号辣椒品种的真实性。结果表明,所试验的18对SRAP引物中有13对引物分别在2个辣椒杂交种和其亲本之间存在扩增条带的多态性,平均每个引物组合扩增的清晰条带数为23.5条,多态性比率为58.89%,其中有3条偏母型引物,2条偏父型引物, 2条互补型引物。用互补型引物DC1-EM9对航椒4号和航椒5号进行了各100粒种子SRAP鉴定,所测纯度分别为100%和97.3%,与田间纯度100%和98.9%非常接近,表明了SRAP分子标记技术是鉴定辣椒一代杂种纯度的有效方法,具有准确、可靠、快速的特点,在辣椒杂交种子纯度室内快速检测中有很大的应用前景。     

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.