36个马铃薯品种的SSR分析

为明确36个马铃薯品种在DNA分子水平上的遗传差异,利用SSR分子标记技术对其多态性进行了分析。试验从90对SSR引物中筛选出适宜于36个马铃薯品种基因组DNA扩增的引物10对,PCR扩增获得301个SSR条带,多态性条带百分率为71.1%。引物STACCA3和SSR111扩增的SSR指纹图谱差异明显,可作为36个马铃薯品种间鉴别的分子依据。36个马铃薯品种间的遗传距离(GD)变幅为0.33～0.85,平均为0.54,其中,大于GD平均值的品种有20个,占供试品种的55.56%。以GD值0.57为基准,将36个马铃薯品种划分成7类,从DNA分子水平揭示出各供试品种间的亲缘关系。     

利用SSR标记鉴定杂交粳稻‘花优14’种子纯度

本研究以杂交粳稻‘花优14’及其亲本为材料,利用SSR分子标记技术,对其多态性进行了引物筛选和种子纯度鉴定研究。从48对广泛分布在水稻12条染色体上的候选SSR分子标记中,筛选得到6对引物,在‘花优14’和其双亲之间表现为稳定的共显性且能将杂交种及其亲本完全区分,利用这些引物对‘花优14’种子进行分子纯度鉴定,并将鉴定结果与田间小区种植纯度鉴定结果相比较,结果显示两者鉴定结果基本一致。因此,最终确定了多态性位点最多且特异性差异最显著的RM274和RM1195标记组合作为核心引物,建立了一套更为快速、有效地鉴定杂交粳稻‘花优14’种子纯度的技术方法。     

利用SSR荧光标记构建20个高粱品种指纹图谱

为建立高粱种子纯度及真实性鉴定技术体系,构建高粱栽培品种DNA指纹图谱数据库是必要的。利用SSR荧光标记技术筛选出36对SSR荧光标记引物,构建我国高粱杂种优势利用以来中晚熟区主推的20个品种的SSR指纹图谱。36对SSR引物共扩增出235个等位基因,平均每个等位基因检测到多态性位点7个,多态性位点变化范围为2~12个。20个高粱品种36个SSR位点的遗传多样性指数和多态性信息量的变化范围分别为0.3490~0.8813和0.3144~0.8696,平均值分别为0.6976和0.6571。从36对SSR引物中筛选到多态性丰富的2对引物作为高粱品种鉴定的特征引物,2对SSR特征引物组合可区分所有供试品种。20个高粱品种的SSR指纹图谱互不相同,可以作为各品种特定的图谱,为品种鉴别提供依据。     

利用DAMD分子标记构建甜菜品种的分子身份证

为了根据遗传背景快速区分和鉴定甜菜品种的真实性和特异性,补充和打破形态学鉴定法的短板和局限,以96份甜菜登记品种为试材,采用DAMD分子标记技术构建了甜菜品种的分子身份证。结果显示,有7条扩增条带清晰、多态性较好的DAMD引物可用于鉴别甜菜品种,这7条引物共检测出103条带,其中多态性条带101条,多态性98.1%;96个品种间的最小遗传距离为0.039,最大为0.485,平均遗传距离0.237。通过聚类分析,96个甜菜品种被分为两类群,类群I仅有54号品种,类群II包含其余95个品种,类群II进一步又分两个亚群。仅利用URP1F、URP17R和URP2R这3条引物组合将96个供试甜菜品种完全区分。利用DAMD引物构建甜菜品种的分子身份证,为快速、高效地鉴定甜菜品种提供了一种新的途径,也为保护育种家和农民的利益提供了保障。     

新疆春小麦SSR指纹图谱的构建

建立快速、准确的品种鉴定方法,是中国种子产业化发展的需要,同时对保护农民以及育种家的利益也具有重要意义。本研究采用SSR标记技术对新疆维吾尔自治区已审定的24个新春系列春小麦品种进行了初步分析,共确定了5对SSR核心引物,其中引物Xgwm 349的多态性最高,可将17个供试材料一次性区分开;引物Wmc47除了可以鉴别出5个供试品种外,还可将其余材料分为4个类群;此外,利用Wmc41、DP 269与Xgwm 304三个引物构建的全部供试品种SSR数字化指纹图谱,可以将所有供试材料完全鉴别出来。     

基于SSR和SRAP标记的苦瓜品种鉴定及亲缘关系分析

本研究应用SSR和SRAP 2种标记对11个苦瓜品种进行鉴定和亲缘关系分析。结果发现,应用筛选的8对SSR引物共扩增条带860条,多态性条带占68.0%,10对SRAP引物共扩增条带961条,多态性条带占79.4%。SSR标记检测到品种间遗传相似系数介于0.344~0.779,平均值为0.652;SRAP标记检测到品种间遗传相似系数介于0.373~0.700,平均值为0.625。聚类分结果发现,在遗传相似系数为0.54和0.52时,SSR和SRAP 2种标记都可以将11个品种分为相同的两组。每对SSR和SRAP引物能平均区分3.1和3.7个品种。最少用3对SSR引物或3对SRAP引物组合就可成功区分11个苦瓜品种。研究结果表明,SSR和SRAP标记均可高效地被用于苦瓜的品种鉴定和亲缘关系分析。     

厚皮甜瓜品种组合SSR指纹图谱构建

采用SSR(Simple sequence repeat )标记技术对21份厚皮甜瓜品种(Cucumis melo ssp. melo) 组合进行分析,初步建立其DNA指纹图谱,为厚皮甜瓜品种DUS测试和品种鉴定奠定基础。从700对SSR引物中筛选23对多态引物组合,对所有供试材料进行分析,共检测出63条多态性条带,平均每个引物多态性条带为2.74条;多态信息含量（PIC）在0.52～0.69,平均0.61。应用其中6对引物组合（CMGAN12、MU7161、F22_85、F21_16、ECM79和MU5499）获得了每个品种组合的SSR特征带,可以将所有供试材料区分,初步建立21份厚皮甜瓜品种组合的SSR指纹图谱,为品种的真伪鉴定和知识产权保护提供有效的科学依据。     

俄罗斯马铃薯种质资源遗传多样性的SSR分析

俄罗斯马铃薯种质资源具有综合抗性强的特点。尤其适合东北三省及内蒙古东部地区种植。为了丰富中国马铃薯品种改良的基因资源,本试验选取54份俄罗斯血缘的马铃薯品种,利用SSR分子标记技术对其遗传多样性进行分析,从DNA分子水平上明确各品种间的遗传差异。本试验从50对SSR引物中筛选出14对多态性好,目的条带清晰的引物,对供试的54份品种进行PCR扩增,共扩增出229个多态性条带,多态性条带百分率到达92.7%。扩增片段在100~1 500 bp。其中引物STM0030可以将供试的54个品种全部区分开。遗传相似性系数的变幅为0.52~0.99,平均为0.68。经聚类分析,在遗传相似性系数0.756处,将供试品种分为10类,从分子水平上揭示了各供试品种间的亲缘关系。     

用SRAP标记分析黄瓜品种遗传多样性及鉴定品种

利用相关序列扩增多态性（SRAP）分子标记技术对35份不同类型的黄瓜品种进行了指纹图谱遗传多态性分析,从38对引物组合中筛选出3个多态性高的引物组合,此3对引物扩增得到的图谱可将35份黄瓜品种完全区分开来。依据SRAP指纹图谱聚类分析结果确定了品种之间的遗传距离以及鉴别的难易程度。用SRAP分子标记技术得到了两个黄瓜品种杂交组合F1与亲本的指纹图谱中的鉴别条带,可以用于黄瓜杂交种的纯度检测。     

SSR分子标记对24个春小麦育成品种的聚类分析

为了进一步了解新疆春小麦品种的遗传基础,给春小麦育种工作提供有益参考,利用SSR分子标记技术对24个新疆春小麦育成品种进行了遗传背景分析。结果表明：41对SSR引物共检测到432个等位位点,其中多态性位点占93.1%,引物多态性信息量（PIC）平均0.86;聚类分析在遗传距离0.8处,供试春小麦品种可分为4个大类,具有亲缘关系的品种并不一定能聚成一类,说明新疆春小麦育成品种间具有很丰富的遗传差异。     

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.     

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.     

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...     

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.     

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.     

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.     

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.