山茶属3种植物花药超低温保存研究

为有效保存山茶属植物的花粉,以茶梅(Camellia sasanqua)、攸县油茶(Camellia yuhsienensis Hu)和多齿红山茶(Camellia polyodonta How)成熟花药为试材,对不同干燥处理的花药进行超低温(液氮,-196℃)保存和水浴解冻的研究。结果表明:不同干燥时间及不同预冻方式对超低温保存后3种山茶属花粉的萌发率有显著影响。茶梅花药经30℃干燥处理4h,含水量为26.92%时,超低温保存后花粉活力最高;攸县油茶花药经30℃干燥处理2~4h,含水量为27.52%~33.71%时,超低温保存后花粉萌发率最高;多齿红山茶花药经30℃干燥处理1~3h,含水量为20.98%~37.95%时,超低温保存效果最佳。3种花药经-26℃预冻处理,超低温保存后花粉萌发率显著高于4℃处理和不预冻处理的对照;超低温保存后38℃(2min)水浴解冻效果最好。3种植物新鲜花药在室温下干燥保存20~40d,花粉活力基本丧失。而经超低温保存半年,3种花药花粉仍具较高的活力,甚至超过保存前的水平。     

黄皮花粉的超低温(LN2,-196℃)保存研究初报

以甜叶黄皮和鸡心黄皮的成熟花粉为试材,采用"培养基发芽法"结合显微镜镜检,对不同干燥处理的黄皮花粉进行了超低温(LN2,-196℃)保存研究。结果表明:新鲜花粉经28℃干燥处理5～6h,含水量为14.6%～19.4%,超低温保存后的生活力最高;花粉在液氮中贮藏14d和180d,其发芽率无明显差异;超低温保存后的花粉发芽时间比对照迟。初步认为黄皮花粉可以在液氮(-196℃)中长期贮存而不显著失去其生活力。     

大豆对SMV数量抗性的育种

为证实潜育期长、病情发展缓慢、最终病情轻的数量抗性的利用价值,在接种SMV-Sa株系条件下,比较了同一遗传背景、不同发病时期、不同病情下大豆品种主要农艺性状的变异.研究表明早期感染SMV对大豆产量、褐斑率等的影响显著大于花期感染;病情指数与大豆产量、单株荚数、单株粒数等存在显著负相关,病情指数越高,对产量等危害越大;通过比较SMV对质量抗性、数量抗性和感病3类大豆品种的影响,证实数量抗性品种在株高、单株粒数以及大豆产量等方面受SMV影响显著小于感病品种,与质量抗性品种接近.说明选育数量抗性品种对控制SMV危害有实质性意义.     

黄淮中北部大豆花叶病毒株系的鉴定与分布

2002-2003年采集了黄淮中北部地区为主的32个县市的大豆SMV病样981份,经初步繁殖鉴定、生物纯化及DAS-ELISA血清学检测,得到95个SMV分离物,根据95个分离物在27个鉴别寄主上的症状反应,最终确定南农1138-2、诱变30、8101、铁丰25、Davis、Bullfalo、早熟18、Kwanggyo、齐黄1号和科丰1号10个品种作为该地区SMV株系的鉴别寄主.利用它们可将95个SMV分离物划分成10个株系群,其中5个与以往鉴定株系群相同,另5个为新发现的株系群,分别将5个新株系群定名为SC-11～SC-15.研究还发现,SC-11株系群所占比例最大,是本地区优势株系;其次为SC-8株系群;SC-11和SC-13株系群分布最广,在黄淮北部各省均有分布.     

6种草本药用植物种子超低温保存技术研究

以草本药用植物杜若、过江藤、夏枯草、皱果苋、罗勒和山香的成熟种子为材料,探讨了含水量和冷冻方法对种子超低温保存的影响。结果表明,经液氮超低温冷冻后,6种草本药用植物种子发芽率较对照组均有显著差异(p0.05);适宜的含水量下,种子经过超低温冷冻后其发芽率甚至高于对照组。3种冷冻方法中,玻璃化冷冻法更适合过江藤和山香种子的超低温保存,缓慢冷冻法更适合皱果苋、杜若和夏枯草种子的超低温保存,直接冷冻法适合于杜若和罗勒种子的超低温保存。所以,液氮超低温冷冻法保存杜若等6种草本药用植物种子是可行的;含水量对超低温保存前后夏枯草、山香和罗勒种子的发芽率影响显著。     

安徽省SMV株系的鉴定及其抗源筛选

为明确安徽省大豆花叶病毒（Soybean mosaic virus,SMV）株系的最新组成、分布及消长动态,以及筛选对流行株系的抗性种质。2009-2010年广泛采集安徽省各大豆主要产区疑似SMV病样461份,采用生物学及血清学方法鉴定得到83个SMV分离物。用全国统一的10个鉴别寄主对这些分离物进行鉴定,共鉴定出14个SMV株系,如SC3-SC9、SC11、SC13-SC15、SC17、SC19和SC22,其中SC5、SC11、SC14、SC15、SC17、SC19和SC22是本研究大豆主产区新发现的。进一步比较分析发现,SMV株系SC3和SC7仍为目前安徽省大豆产区的流行株系,分别占分离物总数的16.9%和25.3%;其次为新发现的强毒株系SC15,在安徽省也有较为广泛的分布,比率为12.1%。针对流行株系SC3和SC7的抗源筛选结果表明,来自参加安徽省区试的149份资源中有中作J8023、中黄45、L85-2308、中涡47号和濉科13等5份材料对SC3表现高抗,中黄45、宿03-4-1-4和鲁06-7等9份材料对SC7表现高抗;来自参加我国南方区试的95份种质资源中有13份对强毒株系SC15表现抗病,占鉴定品种的13.7%。本研究明确了安徽省大豆产区的流行株系及变化趋势,筛选出针对SMV流行株系的抗源,为培育抗病品种和抗病品种布局提供了依据。     

大豆花叶病毒致病基因的克隆与序列分析

通过生物学纯化与血清学鉴定(ELISA)得到5个大豆花叶病毒(SMV)分离物,利用RT-PCR法扩增其CP、HC-Pro、P1和P3基因片段并进行测序。结果表明:5个分离物P1基因全长均为927个核苷酸,编码产生309个氨基酸。同源性分析表明,5个分离物核苷酸序列同源性为88.0%~99.9%,由此推导的氨基酸序列同源性为86.1%~100.0%。此外,5个分离物4个SMV基因CP、HC-Pro、P1和P3长度均为4 137个核苷酸,编码1 378个氨基酸。分析结果显示,5个分离物之间的核苷酸及氨基酸的同源性分别为92.6%~99.3%和95.1%~99.2%。根据系统进化树的分析,结合5个分离物在10个大豆鉴别寄主上的致病性反应,发现SMV的4个基因CP、HC-Pro、P1和P3与SMV的致病力及病样的来源地之间具有一定的关系。同时,这4个SMV基因能够将传统的SMV株系分离物与重组性分离物进行区分。     

不同抗性大豆品种感染SMV后过氧化物酶、多酚氧化酶、超氧化物歧化酶的变化分析

本文采用两个高抗SMV3号株系种质哈91R3-184、哈91R3-301，两个感病品种合丰25、黑农16于真叶期分别接种SMV3号株系，在R1、R3、R5期分别测定过氧化物酶（POD），多酚氧化酶（PPO）、超氧化物歧化酶（SOD）同工酶活性，结果表明：1、抗感病品种未接种健株POD、PPO酶谱构型没有差异，只是活性高低有别，说明抗性与POD、PPO活性有关。2、接种SMV后感病品种POD、SOD酶活性明显高于未接种健株和抗病品种，其POD、PPO部分酶带加宽色深，部分酶带缺失，3、各生育阶段抗感品种PPO、POD、SOD酶活性动态的变化，可作为抗感病品种的生化鉴定指标。     

黄淮和长江中下游地区大豆花叶病毒株系鉴定与分布

通过生物学测定和血清学方法检测了从黄淮和长江中下游地区采集的135个病样，其中81个表现为SMV阳性反应。证明大豆花叶病毒仍为该地区的优势病毒，根据这81个SMV分离物在25个鉴别寄主上的反应，结合分离物来源进行分析，结果表明：(1)黄淮和长江中下游地区大豆花叶病毒可划为SC～1～SC-8八个株系群；(2)从多组鉴别寄主体系中挑选出的南农1138-2、齐黄10号、8101、铁丰25、Davis、Buffalo、早熟18、Kwanggyo、齐黄1号九个大豆品种可以作为一套综合的SMV株系鉴别寄主；(3)弱毒株系群SC-1和SC-3在黄淮和长江中下游地区分布较广，强毒株系群SC-8仅在江苏南京发现。     

2002-2004年国家大豆区试品种对大豆花叶病毒抗性的评价

在接种东北大豆产区SMV主要株系N1、N3和黄淮与南方大豆产区SMV株系Sa、SC3条件下,对最新育成的参加2002-2004年国家大豆区试的134个大豆品种进行了抗性评价,结果表明:接种4个株系后,分别有13个品种(东农L13、汾豆56、汾豆60、汾豆61、晋大74、K丰52-1、航天2号、辽03-20、辽95025-5-4、中作2-29、中豆32、科9208、油春32)和5个品种(铁95025-5-5、铁94037-6、汾豆69、冀99、冀鉴27)分别对4个株系和3个株系表现抗侵染,中黄4、中作016、吉林2001-14等25个品种对1-2个株系表现抗侵染;5个品种(公交03-1212、冀鉴37、秦豆9、淮02-02、滑豆20)对4个株系表现抗扩展.以上品种除可用于生产外,还可作为抗SMV育种的抗源.该批参试品种中,黄淮地区品种的平均病情指数最轻,其次是东北地区品种,然后长江流域,华南地区品种的病情最重.从不同类型品种的病情分析,按黄淮夏大豆、北方春大豆、南方夏大豆、南方春大豆、菜用大豆、热带多熟制大豆的顺序逐步加重.在田间条件下,免疫品种数量不多,占参试品种的7.9%,严重度为1级的高抗品种占47.5%,未发现严重度为4级的高感品种,表明多数品种田间抗性较好.     

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.