柱花草种质遗传多样性的SSR和SRAP分析

应用SSR和SRAP标记,对20份柱花草种质的遗传多样性进行研究。从113对SSR引物中筛选出41对多态性较好的引物,共扩增出229个位点,多态性比率达76.86%,平均每个引物扩增多态性位点4.29个。从224对SRAP引物中筛选出25对多态性较好的引物,共扩增出359个位点,平均每个引物扩增多态性10.72个,多态性比率达74.65%。综合SSR和SRAP两种标记对20份材料计算出的遗传相似系数(GS)为0.65~0.90,表明柱花草种质遗传多样性比较丰富;通过UPGMA聚类分析,把这20份材料聚为3个类群,其中类群Ⅰ又分为4个亚类。     

大麦基因型间SSR标记的多态性及其亲缘关系分析

为了解大麦种质资源的遗传多样性,利用位于大麦7条染色体上的42对SSR引物对42个大麦种质多态性及其亲缘关系进行了分析,结果表明,42对SSR引物在42个大麦品种间均有多态性,共检测到112个等位基因,每一对引物的等位基因个数在2～5之间,平均为2.591个。42对SSR引物的多态性信息含量(PIC)变幅为0.321～0.857,平均为0.433。聚类结果表明,这些大麦基因型间的遗传相似系数分布范围较小,为0.321～0.857,在遗传相似系数值0.550水平上,这些品种聚成4大类。SSR标记揭示多数二棱啤酒大麦和多棱饲料大麦品种分别聚在不同类群中,表明其遗传距离较远,遗传基础较广泛;同一类品种(系)间的分布范围相对较近,表明其遗传基础较狭窄;大麦地方品种遗传背景相对复杂。     

24份木薯(Manihot esculenta)种质的遗传多样性研究

采用产量性状和12个表型性状聚类分析以及SSR标记技术,对不同产地来源的24份木薯(Manihot esculenta)种质遗传多样性进行了研究。结果表明,依据12个表型性状在欧氏距离系数为39.353处可将供试的24个木薯种质分为3类,一些品种的表型性状与地理来源之间存在相关性;利用18对SSR引物对24份木薯种质进行多态性分析,共检测到154条带,其中多态性带145条,每一个位点上检测到5～12条,平均8.6条。材料间相似系数在0.510～0.967之间,平均相似系数为0.695。以相似系数0.78为结合点,可以将材料分为三大类。不同国家和地区来源的材料不能明显聚类,不同淀粉含量、干物质量分数的品种却聚在一起,且没有发现与淀粉含量、干物质量分数相关的特异性条带。农艺性状的聚类结果与SSR聚类的结果有很大的差异,说明木薯在长期的演化和自然选择过程中发生了显著的表型变化。     

石斛兰亲缘关系的SSR分析

利用SSR标记分析石斛兰品种遗传多样性及亲缘关系,为合理利用石斛兰种质资源、培育观赏价值高的石斛兰新品种提供依据.从22对SSR引物中筛选获得11对多态性引物,对28个市场流行石斛兰品种的基因组DNA进行扩增.共获得158条多态性位点,平均每个引物产生14个多态性条位点.材料间遗传相似系数变化范围为0.04～0.85,根据SSR标记的结果,采用UPGMA法进行聚类分析,在相似系数0.295处将28份石斛兰种质分为5类.结果表明,石斛兰品种具有丰富的遗传多样性,遗传基础较宽;SSR标记技术很好地从分子水平上揭示石斛兰品种的遗传背景、亲缘关系.     

不同甜高粱种质的SSR多态性分析

利用SSR标记研究了32份甜高粱种质的遗传变异,从30对SSR引物中筛选出11对扩增产物是具有稳定多态性的引物。11对引物在供试材料中共扩增出112条带,其中多态性带91条,多态性达81．3％,每对引物扩增出5-16条,平均10．2个,每个位点的多态性信息量（PIC）变化在0．429-0．926之间,平均为0．708。32份甜高粱种质间的遗传相似系数变化范围为0．583-0．969,平均值为0．724,揭示出这32份种质的遗传基础相对比较狭窄。UPGMA聚类分析结果表明,32份供试材料在遗传相似系数0．730处被划分为三大类,HE1和HL2的亲缘关系最近,SART和L-32的亲缘关系最远。     

热辣2号辣椒纯度鉴定及优良自交系遗传多样性分析

为了提高种子质量和充分利用辣椒种质资源,应用SSR分子标记对热辣2号杂交种纯度进行鉴定并对部分辣椒优良自交系进行遗传多样性分析。以热辣2号母本材料CAYB02和父本材料CAYB01为模板筛选85对辣椒SSR引物,其中12对引物在亲本间能扩增出明显的多态性,多态性比率为14.12%,多态性标记分别位于辣椒1、3、4、6、7、9、11、12号染色体,利用3对位于不同染色体上的SSR标记对热辣2号黄灯笼椒杂交种的纯度进行鉴定,热辣2号种子纯度为98.79%,标记鉴定结果与田间鉴定结果一致。研究结果表明,利用SSR标记鉴定辣椒杂交种纯度是切实可行的。利用12对多态性明显、稳定可靠的SSR引物对部分辣椒自交系进行遗传多样性分析,共扩增出60条条带,多态性位点比率为100%,平均每对引物检测出5个等位基因。30份辣椒自交系间遗传相似系数变幅为0.33~1.00,平均为0.65,表明供试材料间具有丰富的遗传多样性。聚类分析结果表明,在遗传相似系数为0.47时,可以将中国辣椒和一年生辣椒区分开来。在遗传相似系数为0.85时,30份辣椒优良自交系分为11个类群,辣椒种质遗传关系与地理来源和农艺性状具有一定的相关性。     

62个小麦品种基于EST-SSR标记的遗传多样性分析

为了解从匈牙利、捷克引进的39个欧洲小麦品种的遗传多样性,以23个中国黄淮冬麦区小麦品种为对照,利用55个多态性EST-SSR标记检测参试材料的遗传多态性.结果表明,55个标记在62 个小麦品种中检测到213条差异带,能够将所有品种区分开来;单个引物扩增差异带数目为1～9条,平均为3.87条;多态性信息指数(PIC)为0～0.87,平均为0.53;品种间遗传相似系数为0.48～0.94,平均为0.70.引进品种平均等位变异数高于国内品种,而相似系数却低于国内品种,表明引进品种遗传变异基础大于本研究中的国内品种.聚类分析在相似系数0.69处将62个品种聚为两类,第I类包含匈牙利的2个品种,其他60个品种聚为第II类.第II类又分为四个亚类,其中,第一(II-1)和第三亚类(II-3)包含了引进和国内品种,而第二亚类(II-2)全部为国内品种,第四亚类(II-4)全部为引进的品种.     

小麦穗部组织 EST-SSR标记引物开发及其在小麦遗传多样性分析中的应用

为了筛选光温敏雄性不育系（PTGMS）小麦穗部的EST-SSR 分子标记,探讨其EST-SSR标记用于小麦品种遗传差异研究的可行性,用SSRSCAN软件对PTGMS小麦穗部的3 264条EST序列进行SSR 位点查找,结果得到108条含有SSR标记的序列。设计64对引物并进行PCR扩增及非变性聚丙烯酰胺凝胶(PAGE)电泳。结果显示,64对引物中有41对能在42个小麦品种中扩出PCR条带,有多态性条带的为36对,具有较高的扩增效率。聚类分析结果显示,42个小麦品种的遗传相似系数在0.64~0.87之间,3个PTGMS小麦品种具有较高的遗传相似系数。     

抗稻瘟病水稻品种Dacca6与部分杂交水稻亲本遗传多样性分析

为筛选新的抗稻瘟病种质资源,选取水稻染色体上68对SSR引物,对Dacca6抗稻瘟病材料与其它27个杂交水稻之间的遗传差异进行分析.结果表明,68对引物在28份供试材料中共扩增出251条条带,63对引物具有多态性,多态性位点百分率为92.6％.每对引物扩增出条带的变幅为2～9,平均每对引物扩增出条带数为3.9.在遗传相似系数0.44处可将28份材料聚类为2类,Dacca6与这些材料的遗传差异较大,单独归为一亚类.Dacca6与各材料之间的遗传相似系数在0.330～0.517之间,平均相似系数为0.402.因此,Dacca6可被用来与其它遗传差异较大的亲本或抗源杂交,进行抗病新品种的选育.     

黄淮麦区小麦新品种(系)的遗传多样性分析

为了解黄淮麦区新育成小麦品种的遗传多样性,选用33对SSR引物对2011/2012年度国家黄淮冬麦区(南片)区试42个小麦品种(系)的遗传差异情况进行了分析。结果显示,(1)33对引物共检测到128个等位变异,每对引物检测到等位变异数2～6个,平均3.88个;每个SSR位点多态性信息指数(PIC)为0.09～0.77,平均为0.53。(2)小麦新品种3个基因组的平均遗传丰富度不同,由高到低排序为A>B>D,平均遗传多样性指数为B>A>D。(3)品种间遗传相似系数(GS)为0.15～0.88,平均为0.52。聚类分析结果表明,42个品种被聚为2大类,4个亚类,其中大部分品种聚集于前两个亚类。本研究表明,黄淮麦区小麦区试品种(系)中少数品种具有较大遗传差异,可为亲本利用提供参考,但参试品种总体遗传多样性水平较低。     

Comparative Assessment of the Efficacy of Various Nitrogen Fertilizers

Summary

The efficiency of N fertilizers is usually poor; often less than 50% of the applied N is taken up by the crop. This review focuses on various N fertilizers with respect to the significance of different N loss pathways, namely (i) ammonia volatilization, (ii) dinitrogen and nitrogen oxide emissions, and (iii) nitrate leaching. Further, the significance of biological N immobilization, ammonium fixation and, finally, the impact of nitrate vs. ammonium uptake on crop yield are also discussed. The reviewed literature shows that N fertilizers may differ markedly in their susceptibility to losses. There is, however, considerable scope to improve N efficiency of each N source by proper N management practices.     

Studies on natural repellents against potato tuber moth (Phthorimaea operculella Zeller) in country stores

Summary The effects of the leaves of five plant species, one from each of the generaAmbrosia, Anemone, Eupatorium, Eucalyptus andLantana, on potato tuber moth were investigated under indigenous storage conditions at the Central Potato Research Station, Shillong (1800 m above sea level). Their action was compared with that of a biological insecticide (spores ofBacillus thuringiensis), a chemical insecticide (carbaryl), and an untreated control. The data collected after six months storage on tuber damage, sprout damage and the rotting indicated that the leaves ofLantana aculeata provided most protection to the tubers, reducing damage from over 70% in the check to below 5%, and sprout damage from over 45% to below 3%. Next best wasEucalyptus globulus followed byB. thuringiensis. They may be used on tubers stored for table use or for seed as they had no adverse effect on germination or on the yield of a subsequent crop.     

Mineral composition of some traditional Mexican teas

Teas of plant origin traditionally consumed by the Mountain Pima of Chihuahua, Mexico, were analyzed for mineral nutritional content. Fe, Cu, Zn, Ca, and Mg composition was determined for native teas made from shoots ofTagetes lucida, T. filifolia, Elytraria imbricata, andHolodiscus dumosus, and from root xylem ofCeanothus depressus andPhaseolus ritensis. Native uses of these teas are also described.     

Novel food and non-food uses for sorghum and millets

Sorghum and millets have considerable potential in foods and beverages. As they are gluten-free they are suitable for coeliacs. Sorghum is also a potentially important source of nutraceuticals such antioxidant phenolics and cholesterol-lowering waxes. Cakes, cookies, pasta, a parboiled rice-like product and snack foods have been successfully produced from sorghum and, in some cases, millets. Wheat-free sorghum or millet bread remains the main challenge. Additives such as native and pre-gelatinised starches, hydrocolloids, fat, egg and rye pentosans improve bread quality. However, specific volumes are lower than those for wheat bread or gluten-free breads based on pure starches, and in many cases, breads tend to stale faster. Lager and stout beers with sorghum are brewed commercially. Sorghum's high-starch gelatinisation temperature and low beta-amylase activity remain problems with regard to complete substitution of barley malt with sorghum malt . The role of the sorghum endosperm matrix protein and cell wall components in limiting extract is a research focus. Brewing with millets is still at an experimental stage. Sorghum could be important for bioethanol and other bio-industrial products. Bioethanol research has focused on improving the economics of the process through cultivar selection, method development for low-quality grain and pre-processing to recover valuable by-products. Potential by-products such as the kafirin prolamin proteins and the pericarp wax have potential as bioplastic films and coatings for foods, primarily due to their hydrophobicity.     

In vitro antimicrobial activity of different accessions ofSolanum commersonii Dun. from Uruguay

Summary The in vitro antimicrobial activity of extracts from accessions ofSolanum commersonii Dun. collected in the south of Uruguay was investigated against five microorganisms including the pathogenRalstonia solanacearum. A total of 30 extracts corresponding to organic and aqueous extracts were studied. Interestingly, most of the positive results for growth inhibition were againstR. solanacearum. The extracts were also analyzed for the presence of glycoalkaloids and lectins. Six of the ten aqueous extracts showed lectin presence and a wide variation in the type and amounts of glycoalkaloids, was found. Results indicate that there is no clear relationship between the antimicrobial activity against the five microorganisms screened and the presence or amounts of lectins and glycoalkaloids, traditionally regarded as possible antimicrobial metabolites in theSolanum genus, which indicates the presence of as yet unidentified antimicrobial compounds.     

Extreme resistance to infection by potato virus X in genotypes of wild tuber-bearingSolanum species

Summary Clones derived from thirty-one different accessions (nineteen of Argentine origin) belonging to eightSolanum species were screened for resistance to infection by potato virus X strain cp (PVX cp) by mechanical inoculation of plantlets that had been micropropagated in vitro. Estimates of PVX multiplication obtained by enzyme linked immunosorbent assay and slot blot nucleic acid hybridization allowed the identification of resistant clones derived from five accessions belonging toS. commersonii S. oplocense, S. sparsipilum andS. tuberosum andigena. Resistant genotypes supported PVX concentrations 5 to 15 times smaller than did the susceptible control cultivar Spunta. Graft inoculation test confirmed the presence of extreme resistance similar to that conferred by the ‘immunity’ gene X¹ (also called RX_act).     

Cyanobacteria Secondary Metabolites as Biotechnological Ingredients in Natural Anti-Aging Cosmetics: Potential to Overcome Hyperpigmentation,Loss of Skin Density and UV Radiation-Deleterious Effects

The loss of density and elasticity, the appearance of wrinkles and hyperpigmentation are among the first noticeable signs of skin aging. Beyond UV radiation and oxidative stress, matrix metalloproteinases (MMPs) assume a preponderant role in the process, since their deregulation results in the degradation of most extracellular matrix components. In this survey, four cyanobacteria strains were explored for their capacity to produce secondary metabolites with biotechnological potential for use in anti-aging formulations. Leptolyngbya boryana LEGE 15486 and Cephalothrix lacustris LEGE 15493 from freshwater ecosystems, and Leptolyngbya cf. ectocarpi LEGE 11479 and Nodosilinea nodulosa LEGE 06104 from marine habitats were sequentially extracted with acetone and water, and extracts were analyzed for their toxicity in cell lines with key roles in the skin context (HaCAT, 3T3L1, and hCMEC). The non-toxic extracts were chemically characterized in terms of proteins, carotenoids, phenols, and chlorophyll a, and their anti-aging potential was explored through their ability to scavenge the physiological free radical superoxide anion radical (O₂^•−), to reduce the activity of the MMPs elastase and hyaluronidase, to inhibit tyrosinase and thus avoid melanin production, and to block UV-B radiation (sun protection factor, SPF). Leptolyngbya species stood out for anti-aging purposes: L. boryana LEGE 15486 presented a remarkable SPF of 19 (at 200 µg/mL), being among the best species regarding O₂^•− scavenging, (IC₅₀ = 99.50 µg/mL) and also being able to inhibit tyrosinase (IC₂₅ = 784 µg/mL), proving to be promising against UV-induced skin-aging; L. ectocarpi LEGE 11479 was more efficient in inhibiting MMPs (hyaluronidase, IC₅₀ = 863 µg/mL; elastase, IC₅₀ = 391 µg/mL), thus being the choice to retard dermal density loss. Principal component analysis (PCA) of the data allowed the grouping of extracts into three groups, according to their chemical composition; the correlation of carotenoids and chlorophyll a with MMPs activity (p < 0.01), O₂^•− scavenging with phenolic compounds (p < 0.01), and phycocyanin and allophycocyanin with SPF, pointing to these compounds in particular as responsible for UV-B blockage. This original survey explores, for the first time, the biotechnological potential of these cyanobacteria strains in the field of skin aging, demonstrating the promising, innovative, and multifactorial nature of these microorganisms.     

Marine Pharmacology in 2009–2011: Marine Compounds with Antibacterial,Antidiabetic, Antifungal,Anti-Inflammatory,Antiprotozoal, Antituberculosis,and Antiviral Activities; Affecting the Immune and Nervous Systems,and other Miscellaneous Mechanisms of Action ?

The peer-reviewed marine pharmacology literature from 2009 to 2011 is presented in this review, following the format used in the 1998–2008 reviews of this series. The pharmacology of structurally-characterized compounds isolated from marine animals, algae, fungi and bacteria is discussed in a comprehensive manner. Antibacterial, antifungal, antiprotozoal, antituberculosis, and antiviral pharmacological activities were reported for 102 marine natural products. Additionally, 60 marine compounds were observed to affect the immune and nervous system as well as possess antidiabetic and anti-inflammatory effects. Finally, 68 marine metabolites were shown to interact with a variety of receptors and molecular targets, and thus will probably contribute to multiple pharmacological classes upon further mechanism of action studies. Marine pharmacology during 2009–2011 remained a global enterprise, with researchers from 35 countries, and the United States, contributing to the preclinical pharmacology of 262 marine compounds which are part of the preclinical pharmaceutical pipeline. Continued pharmacological research with marine natural products will contribute to enhance the marine pharmaceutical clinical pipeline, which in 2013 consisted of 17 marine natural products, analogs or derivatives targeting a limited number of disease categories.