六个八倍体小偃麦的选育和鉴定

以中间偃麦草（Elytrigia intermedia）与普通小麦品种烟农15杂交，从其杂种后代中选育出6个细胞学稳定的八倍体小偃麦山农TE183、山农TE185、山农TE188、山农TE198、山农TE256和山农TE347。这些八倍体小偃麦植株健壮、育性正常、穗大多实，高抗白粉病、务锈病等小麦病害。种子醇溶蛋白电泳分析证明，6个八倍体小偃麦醇溶蛋白图谱中均具有亲本中间偃麦草的特异带，并且山农TE183、山农TE185、山农TE198、山农TE256和山农TE347等5个八倍体小偃麦的带型基本一致，为同一类型，而山农TE188为另一类型。细胞学鉴定结果表明，6个八倍体小偃麦的根尖细胞染色体数目为2n=56，花粉母细胞减数分裂中期I（PMCMI）染色体构型为2n=28II，具有高度的细胞学稳定性。以山农TE188和山农TE198分别与中2、中3和中1、中5杂交，对其杂种F1染色体构型分析结果表明，山农TE188与中。和中2、山农TE198与中1和中5的染色体构成是不同的。综合种子醇溶蛋白电泳和细胞学分析结果，初步认为本研究选育的6个八倍体小偃麦与前人选育的中1、中2、中3、中4、中5等5个八倍体小偃麦所携带的中间偃麦草染色体组可能不完全相同。     

小麦-滨麦2D/2Ns异代换系DM2411的分子细胞遗传学鉴定

为进一步挖掘利用滨麦优异基因,并丰富小麦遗传种质资源,利用形态学、细胞遗传学、基因组原位杂交(Genomic in situ hybridization,GISH)、EST-STS分子标记、SSR分子标记等技术,对从八倍体小滨麦M842-16和硬粒小麦D4286杂交F_7代材料中筛选出的1个遗传稳定的小滨麦异代换系DM2411进行了鉴定。细胞遗传学观察表明,DM2411的染色体主要构型为2n=42=21Ⅱ,遗传稳定。根尖体细胞和花粉母细胞的原位杂交研究表明,DM2411含有1对滨麦Ns基因组。SSR分析表明,DM2411可能缺失了小麦2D染色体。EST分析表明,DM2411可能含有滨麦2Ns染色体。形态学调查表明,DM2411的株高极显著降低。     

兼抗白粉病和条锈病的八倍体小偃麦的鉴定

为了选育兼抗小麦白粉病和条锈病的桥梁种质材料,对从中间偃麦草与普通小麦品种烟农15杂交后代中选育的3个小偃麦材料山农TE0537、TE0524和山农TE0543进行了形态学、细胞学和白粉病、条锈病抗性鉴定.结果表明,山农TE0537农艺性状较好,其主要性状介于双亲之间,对白粉病免疫,高抗条锈病,具有高度的细胞学稳定性,其根尖细胞染色体数目为2n=56,PMC MI染色体构型为2n=28II;山农TE0524和山农TE0543对白粉病、条锈病均表现为高抗,根尖细胞染色体数目为2n=55,PMC MI平均染色体构型分剐为2n=2.32Ⅰ 26.22Ⅱ 0.06Ⅳ和2n=1.20Ⅰ 26.90Ⅱ,在细胞学上尚不稳定.研究表明,3个小偃麦材料是小麦白粉病和条锈病的良好抗源,在小麦白粉病和条锈病的遗传改良中具有重要利用价值.     

小麦-滨麦附加易位系DM 5911的创制及其细胞遗传学鉴定

滨麦(Leymus mollis(Trin.)Pilger,NsNsXmXm,2n=28)具有抗旱、耐寒、抗多种真菌和细菌病害、茎秆粗壮、大穗多花等特性,是麦类作物品种改良的优异种质资源。本研究采用细胞遗传学方法对由八倍体小滨麦M842-16与硬粒小麦品种D 4286杂交F6代选育出的1个附加易位系DM 5911进行了鉴定和农艺性状分析。细胞学镜检显示,DM 5911的染色体构型为2n=44=22Ⅱ;根尖体细胞原位杂交鉴定显示,DM 5911含有2条完整的Ns染色体和2条易位的Ns染色体;花粉母细胞原位杂交鉴定显示,DM 5911的2条完整Ns染色体和2条易位Ns染色体可以进行正常的联会配对和遗传。表明DM 5911是1个遗传稳定、包含1对完整的Ns染色体和1对易位Ns染色体的小滨麦附加易位系。形态学调查显示,DM 5911在株高和分蘖数等农艺性状方面得到了明显的改善。该附加易位系作为进一步创制小滨麦小片段染色体易位系的重要种质材料,可用于小麦染色体工程育种与遗传改良。     

一个大穗型小麦-黑麦异代换系的细胞学和SSR鉴定

为了深入研究大穗型小麦的遗传基础,利用细胞学和SSR方法对从普通小麦与六倍体小黑麦杂交后代中选育的大穗型小麦-黑麦材料7-25进行了鉴定.结果表明,品系7-25的根尖细胞染色体数目为2n=42,花粉母细胞减数分裂中期I(PMC MI)绝大多数细胞内可观察到21个二价体,平均染色体构型2n=20.94Ⅱ 0.11Ⅰ,它与中国春杂种F1的多数花粉母细胞染色体构型为2n=20Ⅱ 2Ⅰ,因此表明品系7-25 是一个小麦-黑麦的二体异代换系.使用位于黑麦1R～3R、5R～7R染色体上的黑麦特异的20对SSR引物,其中有2对引物SCM268和SCM120能在7-25品系中稳定地扩增出黑麦特异染色体片段.SCM268、SCM120分别位于黑麦5R染色体的短臂和长臂上.综合细胞学和SSR分析结果,进一步确定品系7-25为小麦-黑麦5R代换系.     

抗条锈病小麦-滨麦衍生后代的分子细胞遗传学鉴定

为了有效挖掘滨麦优异的基因资源,利用形态学、细胞学、荧光原位杂交(FISH)、基因组原位杂交(GISH)和分子标记等技术,对小麦-滨麦衍生后代M13063-3-3进行了鉴定。结果表明,M13063-3-3的染色体构型为2n=44=22Ⅱ。以滨麦基因组DNA为探针的原位杂交结果显示,二条染色体有杂交信号,且能配对,表明两条外源染色体是滨麦的一对同源染色体。SSR、EST和PLUG标记分析表明,M13063-3-3附加的滨麦染色体归属于第6部分同源群染色体。A-PAGE电泳分析表明,M13063-3-3在α区具有滨麦染色体特征带,进一步验证了附加的滨麦染色体与小麦第6部分同源群染色体有部分同源关系。田间条锈病调查结果表明,M13063-3-3对条锈菌生理小种条中31号、条中32号和条中33号混合菌种表现高抗。因此,M13063-3-3是一个附加了一对滨麦第6部分同源群染色体的抗条锈病的普通小麦材料,为小麦抗病育种提供了新的种质资源。     

抗条锈病普通小麦-滨麦6BS·6NsS附加易位系的分子细胞遗传学鉴定

易位系是向小麦转移外源种属优异基因的重要种质资源。普通小麦-滨麦衍生系M13063A-1由小麦-滨麦第六部分同源群二体异附加系材料连续自交获得。为了给普通小麦-滨麦衍生系M13063A-1的利用提供依据,本研究利用形态学、细胞学、原位杂交、分子标记等技术,对该材料进行了鉴定。细胞学鉴定结果显示,M13063A-1有丝分裂中期染色体数目为44条,减数分裂中期I染色体构型为2n=22Ⅱ,且在减数分裂后期Ⅰ可均等分离。原位杂交结果表明,M13063A-1含有42条普通小麦染色体和1对普通小麦-滨麦易位染色体,易位染色体长臂为滨麦Ns基因组染色体片段,短臂为6BS。分子标记分析确定M13063A-1携带的滨麦染色体片段为6NsS。成株期条锈病抗性鉴定显示,M13063A-1抗条锈菌生理小种条中31和条中32。因此,M13063A-1是一个抗条锈病的普通小麦-滨麦6BS·6NsS附加易位系,可以用作小麦抗病育种的桥梁材料。     

普通小麦与偏凸山羊草代换系的细胞学和RAPD鉴定

为了解偏凸山羊草与普通小麦杂种后代抗白粉病种质BC5-2的遗传组成,对其进行了细胞学和RAPD鉴定。结果表明,BC5-2根尖细胞染色体数目为2n=42,花粉母细胞减数分裂中期(PMC M)染色体构型为2n=21。经核型和C-分带分析初步证明BC5-2为偏凸山羊草的双代换系,其中一对为偏凸山羊草的2MV染色体,另一对为6MV染色体,在BC5-2中被代换的小麦染色体是1B和6A染色体。对BC5-2及其亲本进行RAPD分析,在100个随机引物中有2个引物在BC5-2中扩增出偏凸山羊草的特异DNA带,它们分别记为S2011550、S20031000,进一步证明BC5-2是一个普通小麦与偏凸山羊草的双代换系。     

小麦-滨麦衍生系18DM134的分子细胞遗传学及赤霉病抗性鉴定

滨麦[Leymus mollis(Trin.) Pilger]作为小麦的野生亲缘种之一,具有抗寒、抗旱、耐盐碱等优良特性,同时对多种小麦病害具有良好抗性,是小麦遗传改良的重要基因资源。本研究前期从八倍体小滨麦M842和硬粒小麦D4286的杂交后代中筛选出一个抗赤霉病的衍生系18DM134,为给该材料的利用提供依据,本研究利用细胞遗传学、原位杂交、液相芯片、分子标记等技术对其染色体组成进行鉴定,并对其农艺性状和赤霉病抗性进行调查。细胞学观察结果显示,18DM134的染色体构型为2n=42=21Ⅱ。原位杂交结果显示,18DM134含有38条小麦染色体、2条完整的Ns染色体以及2条易位染色体,其中整条6A染色体和5DS染色体缺失,2条Ns染色体片段易位到3DS染色体,2条3DL染色体易位到5DL染色体。液相芯片和分子标记分析结果显示,18DM134中来自滨麦的6Ns染色体替换了小麦6A染色体,部分5Ns染色体片段与3DS染色体发生了易位,5DS染色体缺失。因此,18DM134为小麦-滨麦代换易位系,其染色体组成为12A+14B+10D+2(6Ns)+2(T3DS-5Ns片段)+2(T3DL-...     

小麦-茸毛偃麦草异附加系Y176-3的分子细胞遗传学鉴定

为了解茸毛偃麦草（Thinopyrum intermedium ssp.trichophorum）与小麦经过杂交、回交所选育的小偃麦新种质Y176—3的遗传特性,对该系进行了抗条锈性鉴定与：分子细胞学分析。结果表明,Y176—3对当前的条锈病流行小种和新小种免疫。其根尖细胞染色体数目为2n=44,有2对随体,花粉母细胞减数分裂中期I（PMCMI）染色体构型为2n=22Ⅱ。利用C-带分析,观察到Y176-3中可能附加了一对来自茸毛偃麦草的端部有强带的短染色体。以拟鹅观草（Pseudoroegneria spicata,2n=14）DNA作探针、中国春基因组DNA为封阻进行的原位杂交结果表明。Y176-3含有2条较短的茸毛偃麦草染色体,该染色体属于St组,推测新种质Y176-3中导入的来自茸毛偃麦草的St染色体可能携带新的抗条锈病基因。     

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.