湖南省发展玉米生产的途径与对策

分析了湖南省发展玉米生产的潜力，提出了发展玉米生产的主要途径，并对发展玉米生产的技术对策——玉米科研应解决的关键技术问题提出了意见。     

玉米生产信息化咨询服务平台的构建

本研究以玉米生产信息化为对象,针对目前我国玉米生产过程中存在的问题,充分利用现代信息技术手段,建立了服务于玉米生产全过程的14个数据库及其管理系统,开发了适合我国国情的专家在线咨询服务系统和玉米生产可视化远程咨询服务系统等远程应用软件,通过"中国玉米网"集成构建了玉米生产信息化咨询服务平台,为玉米产业的信息化提供支持。玉米生产信息化咨询服务平台已经在科技入户示范工程中推广应用,并获得了较好的服务效果,为农业生产信息化的实现提供有益的借鉴。     

浙江省玉米产消现状及发展趋势探讨

玉米是浙江省重要的旱粮作物。近年来,在鲜食玉米迅速发展的带动下,玉米生产得到了恢复性的增长,初步形成了具有南方特色的鲜食玉米产业。根据浙江省玉米生产和消费现状以及有利条件,探讨了浙江省玉米生产的发展趋势和主推技术。     

优化粮食作物结构 大力发展玉米生产

针对湖南粮食作物结构不合理，玉米严重缺乏的现象，分析了全省玉米生产的现状及发展玉米生产的有利因素，提出了解决玉米不足的方案，即“优化粮食作物结构，大力发展玉米生产”，阐述了全省发展玉米生产的对策。     

玉米瘤黑粉病的发生规律及防治措施

玉米瘤黑粉病又称玉米黑粉病,是威胁玉米生产的一类重要病害,近年来玉米瘤黑粉病在我国玉米主产区发病呈上升趋势,严重危害了我国玉米主产区的玉米生产。对玉米瘤黑粉病的发病症状进行了详细描述,并对玉米瘤黑粉病的发生规律进行了研究,同时探讨了玉米瘤黑粉病的综合防治措施。     

中美玉米生产贸易与比较优势分析——基于成本效益与生产率的视角

在分析中美玉米生产贸易变化趋势的基础上,按照李嘉图比较优势理论研究中国和美国玉米生产的相对比较优势。结果表明,美国玉米生产资金和技术密集决定了美国玉米生产具有明显的竞争优势。与美国相比,中国在玉米生产的土地生产率、技术效率等方面偏低。在相对比较优势方面,中国玉米生产比大豆生产稍具优势,与其他粮食作物相比均不具备比较优势。提高中国玉米生产效益、降低玉米生产成本,需要规范农资市场,实现适度规模经营,加强玉米生产技术集成创新与推广,改造中低产田,实施“沃土工程”。     

基于GIS的吉林省玉米生产发展时空变异分析

在吉林省玉米生产统计数据库建立的基础上,利用地理信息系统工具软件ArcView和MapGis制作吉林省历年玉米播种面积、单产和总产分布图,对吉林省玉米生产的时间和空间分布进行分析,阐述了吉林玉米生产时空变异的特点和发展趋势。对目前吉林省玉米生产的前景、限制因素以及发展对策进行了分析。结果表明：进入90年代,吉林省玉米生产发展迅速,播种面积、单产和总产均有较大幅度增加,玉米整体生产水平较高。以中部地区玉米生产水平最高,包括农安县、榆树县、扶余县、公主岭市等。目前吉林省玉米的生产已达到一定的规模,宜在稳定中求发展,适当压缩种植面积,调整作物布局,努力提高单产水平,改善玉米品质,加速产业化进程。     

山东省玉米的生产现状与发展策略

简要介绍了山东省玉米供需状况、玉米价格变动情况和玉米生产概况,分析了山东省的玉米生产潜力和存在的问题,提出了发展山东省玉米生产的基本思路和提高玉米产量的途径。     

发展玉米生产的对策措施

盐城是江苏省玉米生产大市,玉米面积占全省的五分之一。为更好地适应市场农业新形势,进一步提高玉米生产水平和经济效益,发挥玉米大市的优势,作者在分析玉米生产现状的基础上,阐述了发展玉米生产的对策措施,提出了普及紧凑型杂交品种、推广群体质量栽培、发展立体高效种植、开发优质特用玉米等技术关键。     

安阳市县域玉米比较优势分析与布局研究

通过应用综合比较优势指数法,对安阳市玉米生产县域的比较优势进行了测定和差异分析。结果表明,安阳市玉米生产不同县域之间综合比较优势存在着很大的差异,应按照比较优势进行玉米生产结构的调整,实现玉米生产的合理布局和专业化生产,以充分发挥玉米生产的比较优势。     

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.