氮离子注入对同源四倍体水稻成熟胚组织培养体系的影响

选择3份同源四倍体水稻为材料,研究了氮离子注入对其成熟胚诱导愈伤组织和分化成苗的影响。结果显示,低剂量范围(1.0×1016~2.0×1016ions/cm2)的N 注入能明显提高愈伤组织诱导率;无论离子注入剂量大小,N 注入能明显改善愈伤组织的发育状态,抑制其褐化衰老的进程,提高愈伤组织的绿苗分化率。     

N+离子注入对同源四倍体水稻种子萌发的影响

以同源四倍体水稻IR36(4)为材料,研究了不同剂量的低能(25 keV)N 离子注入对种子萌发的效应,结果表明,低能N 离子注入对种子的萌发有一定影响。在低剂量(2×1016N /cm2)时,N 注入对IR36(4)种子萌发起到刺激作用,种子的存活率、吸水率、幼苗淀粉酶活性相对CK都有所提高;当注入剂量在2×1016~10×1016N /cm2范围内,N 注入对IR36(4)种子萌发起抑制作用,表现为种子存活率显著降低、淀粉酶活性下降、膜透性增大。     

金钱树四倍体的诱导与鉴定

以金钱树块茎为材料,采用秋水仙素溶液处理不定芽生长点,研究秋水仙素浓度和处理时间的诱变效果。结果表明：0.1%的秋水仙素溶液浸泡处理块茎的不定芽48 h效果最好,其诱导率为30%。通过流式细胞仪对金钱树植株DNA相对含量的测定,鉴别出四倍体和嵌合体。四倍体植株与二倍体植株在叶厚、保卫细胞大小、气孔密度等方面存在明显差异,其中气孔的形态及密度可作为鉴别四倍体、嵌合体和二倍体的重要性状。     

氮离子束注入和钴60伽玛辐射对大豆产量性状和品质的影响

分别以3种剂量的N离子束注入(4×1016,6×1016和8×1016 N+ ·cm-2)和3种剂量的60C o-γ射线辐射(100,150和200 Gy)处理4份大豆干种子,在相同种植条件下对其M6代产量性状和品质进行研究,比较2种处理方法对大豆产量性状及品质的诱变效应.结果表明:与对照相比,新大豆3号4×1016N+·cm-2离子束注入处理单株荚数显著增加,6×1016N+ ·cm-2离子束注入处理产量极显著增加;合99-756 8×1016 N+ ·cm-2离子束注入处理单株粒数和单株粒重显著减少,6×1016N+ ·cm-2离子束注入处理百粒重显著减少,100 Gy60 Co-γ射线辐射处理蛋白质含量显著降低,100,150和200 Gy60 Co-γ射线辐射使脂肪含量显著提高;新大豆8号4×1016和8×1016 N+ ·cm-2离子束注入、100和200 Gy60Co-γ射线辐射处理单株粒重显著减少,4×1016和6×1016 N+ ·cm-2离子束注入及200 Gy60Co-γ射线辐射处理产量极显著或显著增加;N离子束注入和60Co-γ辐射对石大豆2号产量、各产量构成因素及品质的影响差异不显著.因此,诱变育种目标应根据材料的敏感性、诱变方法和剂量综合确定.     

基于DH系的种质基础和秋水仙素浓度对玉米单倍体加倍效果的研究

以先玉335为母本、高频孤雌生殖诱导系G5为父本杂交诱导产生的单倍体为实验材料,研究秋水仙素浸芽加倍处理玉米单倍体的最佳浓度和时间。结果表明,秋水仙素浓度为0.7 mg/m L、浸芽8 h处理下的玉米单倍体加倍率最高,高达14.4%;秋水仙素浓度为0.8 mg/m L、浸芽8 h处理下的单倍体加倍率次之,为12.1%。以自交系PHB1M、PH4CV、PH6WC、PHGJ4和DH系Z2、Z8为亲本组配的PHB1M×PH4CV、PHB1M×Z2、PH4CV×DZ2、PH6WC×PHGJ4、PH6WC×Z8、PHGJ4×Z8组合为母本,以G5为父本,研究玉米DH系对杂交后代加倍率的影响,结果表明,PH4CV×Z2(26.2%)、PHB1M×Z2(25.8%)、PHGJ4×Z8(23.3%)和PH6WC×Z8(21.3%)的单倍体加倍率显著高于PHB1M×PH4CV(13.5%)和PH6WC×PHGJ4(8.4%),以DH系为亲本组配选系基础材料可显著提高玉米杂交组合的单倍体加倍率。     

君子兰二倍体与四倍体叶片性状的比较研究

[目的]观察秋水仙素离体诱导后的四倍体君子兰形态性状是否发生改变,为其多倍体诱导及鉴定提供更多依据。[方法]以移栽后的2年生君子兰二倍体和秋水仙素诱导获得的四倍体株系为材料,对不同倍性君子兰的叶片厚度、长度、宽度以及叶片下表皮气孔密度、大小、叶绿体数进行观察比较。[结果]君子兰加倍植株的性状稳定,四倍体君子兰叶片变厚、变短、变宽,且表面粗糙,生长缓慢;二倍体君子兰叶面光滑,叶薄,生长较快。此外,四倍体君子兰的气孔(40.5μm×12.3μm)和保卫细胞(59.9μm×21.9μm)明显变大,气孔密度(14.3个/mm²)变小。[结论]秋水仙素离体诱导君子兰所获得的四倍体植株性状稳定,叶片和气孔性状可以作为判断君子兰是否加倍的辅助指标。     

离子束处理甜菜杂交种当代效应研究

培育和改良具有优质、高产的作物新品种是品种选育和资源利用的重要研究内容。本研究以甜菜杂交种为处理材料,用N+离子作为诱变源,用35kev的能量,分别以40次、60次脉冲,注入剂量4×1016/cm2、6×1016/cm2进行激发诱变,甜菜杂交种的产量、含糖率均有明显的提高,为甜菜杂交种处理获得当代效应提供了有益参考。     

秋水仙素对猪屎豆的诱变及同源四倍体种质创制的研究

猪屎豆是重要的农业植物资源,在绿肥、饲用和药用等方面都有重要的开发潜力,然而目前关于猪屎豆的品种培育还处于空白,生产上缺乏优良品种导致生产性能参差不齐的问题突出,开展多倍体育种研究可为今后猪屎豆种质资源创新利用和培育新品种奠定材料基础。本研究以二倍体猪屎豆为实验材料,通过不同质量浓度秋水仙素和不同处理时间对猪屎豆露白种子进行多倍体诱导,探讨秋水仙素对二倍体猪屎豆的诱变效果,并利用流式细胞倍性检测和根尖染色体核型分析对诱变后代的倍性进行检测,进一步比较分析二倍体和同源四倍体的气孔和保卫细胞大小以及叶片和种子形态等特征变化。结果表明：与对照相比,秋水仙素处理抑制了猪屎豆种子胚根的生长和下胚轴的伸长,使种子胚轴发生诱变而缩短变粗。研究发现以100 mg/L的秋水仙素浓度浸泡12h时猪屎豆种子四倍体诱导率最高,为13.33%,总体效果最佳。与二倍体相比,同源四倍体植株叶片下表皮的气孔长度和宽度、保卫细胞长度和宽度显著增加而气孔密度显著降低;同源四倍体植株的叶片宽度和叶柄宽度显著增加,而叶片长度和叶柄长度显著缩短;同源四倍体植株的叶形指数显著减小。此外,同源四倍体植株所获种子较二倍体显著增大,种...     

药用万寿菊多倍体的诱导与特征分析

为获得四倍体药用万寿菊材料,采用秋水仙素对药用万寿菊‘内蒙1号’的种子进行多倍体诱导研究。以0.15%浓度的秋水仙素处理露白的万寿菊种子24 h,幼苗变异率较佳,可达到56%。幼苗定植于田间,初步筛选并标记形态变异植株,自花授粉后采收种子播种并观测子代形态指标,对形态变异明显的植株进行流式细胞仪检测,确定获得15株纯合四倍体。通过将四倍体与二倍体进行比较,四倍体植株茎粗、栅栏组织厚度、栅栏组织与海绵组织的比例和单朵花重量显著高于二倍体植株,四倍体植株总叶量、叶宽、叶长、叶长宽比、叶片气孔密度和单株花朵数量显著低于二倍体植株。获得的四倍体万寿菊植株单株花总重量比二倍体显著增加。     

秋水仙素处理后水稻种子内胚乳蛋白的差异性比较分析

经过秋水仙素对二倍体水稻品种圭630（2）处理后,其后代材料在蛋白质水平上表现出明显的差异性。染色体组的倍性水平对水稻种子内胚乳蛋白的表达量有明显的影响。经过秋水仙素处理后,在具有嵌合性特征的植株上大粒种子与原始亲本的种子在总蛋白含量上存在着明显的差异,大粒种子与小粒种子的差异也很明显。染色体组的多倍化对原始亲本的胚乳蛋白含量有明显的影响,由此所获得的同源四倍体水稻株系,其种子内的蛋白质含量比较多。SDS—PAGE分析结果表明,经过秋水仙素诱导后,试验材料的种子内蛋白质亚基的类型没有出现新的变异,而蛋白质亚基的表达量发生了明显的变化。     

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).