中国西南地区小麦品种(系)遗传多样性的SSR分析

为了给中国西南地区小麦新品种选育以及杂种优势研究提供依据,采用微卫星分子标记(SSR)对2005～2006年西南地区参加国家小麦区试及预试的33个小麦品种(系)进行了遗传多样性分析,筛选出24对扩增谱带稳定的引物,共检测到126个等位基因变异,每对引物检测等位基因3～11个,平均5.25个.33个品种(系)之间的遗传相似系数为0.373～0.794,平均为0.597.品种间遗传相似系数变幅较大,表明西南麦区小麦品种(系)间存在着不同程度的遗传多样性差异.用UPGMA法可将33个品种(系)分为6个类群,聚类结果在一定程度上反映了它们之间的亲缘关系.     

甘蓝型黄籽油菜SSR标记遗传多样性

利用 42对SSR引物对19个甘蓝型黄籽油菜品种(系)进行遗传多样性分析,共检测出336个等位基因,每对引物在不同品系间的等位基因数在2～21之间,平均位点为8个.位点多态性信息含量为0.17～0.85,平均为0.73.对SSR扩增结果进行UPGMA分析,可将19个品种(系)分为4个群体,聚类结果与系谱来源比较一致.并且只需NAS99、NAS98、NAS91及NAS31 4对多态性高的引物即可将19个材料区分开来.     

部分水稻不育系的指纹图谱构建和遗传多样性分析

利用56对SSR引物对20个水稻不育系进行了DNA指纹图谱构建和遗传多样性分析。结果表明,56对SSR引物在供试不育系中共扩增出191个多态性片段,平均每对引物可检测出3.41个等位基因(变幅2~7个)。供试引物的平均多态性频率为0.52,平均PIC值为0.50,平均有效等位基因数为2.20。经聚类分析,20个不育系间的遗传相似系数变幅为0.51~0.93,以遗传相似系数0.65为阈值,可将供试不育系分为3个群,聚类分析结果与亲缘系谱表现出较好的一致性。     

南方主要两系不育系遗传多样性分析及指纹图谱构建

分析水稻两系不育系遗传多样性和构建指纹图谱,可为两系不育系选育与组合选配、品种真实性和纯度鉴定提供理论依据。以目前中国南方广泛应用的11个水稻两系不育系为研究材料,利用分布于水稻12条染色体上的48对SSR引物,结合荧光毛细管电泳检测方法,进行遗传多样性分析,并构建指纹图谱。结果表明,48对SSR引物在供试材料中共扩增出122个多态性片段,平均每对引物可检测出2.54个等位基因,平均PIC值为0.412,平均有效等位基因数为1.96;11个不育系间的遗传相似系数变幅为0.45～0.93,平均为0.64,遗传背景趋同,亲缘关系较近;以遗传相似系数0.58为阈值,将供试不育系分为3个群:株1S及其衍生系聚为Ⅰ群,广占63S单独为Ⅱ群,其他不育系聚为Ⅲ群。选用12对多态性较高的SSR引物构建的指纹图谱能区分11个两系不育系。     

大麦DUS测试标准品种的遗传多样性分析及指纹图谱的构建

为对大麦种子的真伪进行有效监控,防止假冒伪劣品种进入市场,也为新品种登记测试以及种质资源遗传多样性分析提供参考,采用SSR标记技术对29个大麦DUS测试标准品种进行了遗传多样性分析和指纹图谱的构建.利用筛选出的28对有多态性的SSR引物共扩增出125个等位基因,每对引物可扩增出3～7个等位基因,平均4.46个等位基因,每对引物在29个品种中的PIC值为0.25～0.81,平均为0.62.聚类分析表明,29个大麦DUS测试标准品种可聚成4类,具有较远的亲缘关系,这些材料首先按照穗棱型进行聚类,表明不同穗棱型品种间存在较大遗传差异.构建了29个大麦DUS测试标准品种在28个SSR位点上的指纹图谱.     

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。     

中国西南地区小麦品种（系）遗传多样性的SSR分析

为了给中国西南地区小麦新品种选育以及杂种优势研究提供依据,采用微卫星分子标记（SSR）对2005～2006年西南地区参加国家小麦区试及预试的33个小麦品种（系）进行了遗传多样性分析,筛选出24对扩增谱带稳定的引物,共检测到126个等位基因变异,每对引物检测等位基因3～11个,平均5．25个。33个品种（系）之间的遗传相似系数为0．373～0．794,平均为0．597。品种间遗传相似系数变幅较大,表明西南麦区小麦品种（系）间存在着不同程度的遗传多样性差异。用UPGMA法可将33个品种（系）分为6个类群,聚类结果在一定程度上反映了它们之间的亲缘关系。     

西双版纳糯玉米地方品种遗传多样性分析

利用SSR标记对西双版纳的36个小糯玉米地方品种和2个对照品种进行遗传多样性研究。从800余对SSR引物中筛选出100对多态性好、稳定性高的SSR引物。结果表明, 这100对SSR引物在36个糯玉米地方品种中共检测出353个等位基因, 每对引物检测出2～8个, 平均为3.53个, 平均多态性息量(PIC)为0.53, 平均标记索引系数(MI)为2.00。聚类分析表明, 糯玉米地方品种聚为6个类群, 与对照品种相比, 地方品种独立成群。     

利用ISSR分子标记进行不同来源大豆品种的分类

采用ISSR分子标记技术对不同来源大豆品种(系)进行了分类研究,对UBC ISSR801-850引物进行筛选,发现有11个引物没有产物,选出39个引物具有扩增产物,一般每个引物可以扩增出1-6条带,产物片段大小多在831-3530b之间.39个引物共扩增出121条带,其中多肽性带47条,占38.84%.每个引物平均可扩增出带数为3.1条;其中多肽性带数为1.21条.ISSR引物扩增的结果表明,ISSR分子标记技术能很好地用来区分不同来源的大豆品种(系).不同大豆品种(系)因其遗传背景不同,经ISSR引物扩增出来的谱带数也不一样,而且不同品种(系)还具有特异性的标记谱带.另外,对沈农系列大豆品种(系)的生产力与本试验采用的日本大豆品种的比较分析可以看出,沈农系列大豆品种(系)的生产力要高于日本大豆品种的生产力.     

33个育成花生品种遗传多样性分析

利用75对SSR标记引物对33个育成花生品种进行遗传多样性分析,结果表明,其中有10对标记引物扩增出多态性,共检测到33个多态等位点,每对引物分别检测出4～8个等位点变异,平均为6.0个,33个花生品种间的遗传相似系数在0.242～1.000之间,平均为0.621。聚类分析结果表明33个参试花生品种在遗传相似系数0.600处分为2个类群,亲本来源相近的品种优先聚在一起。     

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.     

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.     

Recent Modifications of Chitosan for Adsorption Applications: A Critical and Systematic Review

Chitosan is considered to be one of the most promising and applicable materials in adsorption applications. The existence of amino and hydroxyl groups in its molecules contributes to many possible adsorption interactions between chitosan and pollutants (dyes, metals, ions, phenols, pharmaceuticals/drugs, pesticides, herbicides, etc.). These functional groups can help in establishing positions for modification. Based on the learning from previously published works in literature, researchers have achieved a modification of chitosan with a number of different functional groups. This work summarizes the published works of the last three years (2012–2014) regarding the modification reactions of chitosans (grafting, cross-linking, etc.) and their application to adsorption of different environmental pollutants (in liquid-phase).