咖啡光合速率生理生态的研究

（１）不同荫蔽度下，大田咖啡叶片的各生理参数值具明显差异：光合速率、蒸腾速率、气孔密度和干湿重比都比无荫蔽的为最大，９５％荫蔽度的最小，４０％荫蔽度的居中；气孔张开率和水势则以无荫蔽的为最小，９５％荫蔽度的最大，４０％荫蔽度居中。（２）无荫蔽和４０％荫蔽地咖啡光合速率的日变化呈不对称的双峰曲线，１４：００强光下出现“午休”，而９５％荫蔽地咖啡的光合速率日变化呈单峰曲线，没有“午休”现象，峰顶位于１     

不同玉米自交系光合特性的研究

通过对20个玉米自交系单叶光合速率的研究表明：(1)玉米自交系间单叶光合速率存在极显著的差异。(2)玉米自交系的光合速率随生育时期的推延而呈单峰曲线变化，以抽雄吐丝期为最大。自交系间的差异则随着生育时期的推延而逐渐增大。(3)在生态条件差异较大的海南和北京，不同自交系光合速率值高低的稳定性变差。(4)聚光分析的结果表明，自交系在光合性能两个主要性状—净光合速率和叶面积方面表现出多种类型。     

花生群体光合速率发展动态和日变化

花生叶面积系数（ＬＡＩ）、群体净光合速率和群体呼吸速率分别在播后８２、９０和９０９５天达到高峰。ＬＡＩ与群体净光合速率的关系可分为播后８２天前的相关和其后的非相关阶段。ＬＡＩ与群体呼吸速率在播后５０天前同步增长；５０—８２天ＬＡＩ增加快，群体呼吸速率增加慢；８２９０天ＬＡＩ逐渐下降．群体呼吸速率迅速增加；９８天后同步下降四个阶段。群体净光合速率与群体呼吸速率的关系可分为播后５０天期间同步增长；５０—８０天关系不明显和９８天后同步下降的三个阶段。在不同生育时期，群体呼吸速率一天中均呈单峰曲线变化。群体净光合速率因品种而异，在苗期，海花１号一天中呈双峰曲线变化，并有严重午休现象，鲁花１１号则呈偏峰型。播种３０天后，两品种的群体净光合速率一天中均呈单峰曲线变化，１２∶００时达到高峰，早上６∶００７∶００时前、晚１７∶３０－１９∶００时后为负值。     

灌水量与夏玉米光合性能及产量的关系

利用大型防雨设施池栽,研究灌水量与夏玉米光合性能及产量的关系。结果表明,灌水量与夏玉米光合性能及产量呈高度正相关,不同灌水量对群体光合速率、单叶光合速率、光合速率日变化、叶面积发展动态、干物质积累量及干物质生产率产生显著差异,并随生育进展而加剧。根据产量与耗水量的关系,夏玉米13 500 kg/hm²产量水平的耗水量在630 mm左右,9 000 kg/hm²产量水平的耗水量在490 mm左右,200 mm左右为夏玉米经济产量形成的耗水临界值。穗期、花粒期土壤水分状况不同是导致产量及光合性能差异增大的重要原因之一,保证夏玉米中、后期水分适宜是提高光合性能及产量的重要条件之一。     

鼓粒期芸豆净光合速率日变化研究

运用CB-1102型光合蒸腾作用测定系统,研究了芸豆鼓粒期的净光合速率（Pn）日变化。结果表明：芸豆叶片净光合速率（Pn）日变化呈单峰型曲线,无光合午睡现象。上午10：00光合速率最大;11：00蒸腾速率最快;气孔导度的变化趋势与光合速率一致,10：00出现最大值;胞间CO2浓度呈现“早晚高,中间低”的变化规律。     

复合群体中玉米光合特性日变化研究

通过对小麦/玉米复合群体中玉米的光合速率、光合有效辐射、蒸腾系数、水分利用率、相对湿度、叶室温度、叶片温度和二氧化碳浓度等生态生理指标在一日内的变化进行测定、分析。结果表明:Pn、PAR、Ct、Lt和Tr的日变化均“为单峰型”曲线,其变化趋势一致。CO2浓度和RH%的日变化不明显,Sr的日变化也“为单峰型”曲线,但与Pn的相反。相关分析表明,光合速率(Pn)与PAR呈极显著正相关,与Tr的相关性达显著水平,Pn与Sr呈显著负相关,PAR与Ct、Lt、Tr呈显著相关。在水肥满足的条件下,影响群体Pn的主要生态因子是PAR,要提高复合群体中玉米的经济产量主要靠调整群体结构来完成,即选择株型紧凑的玉米品种不仅能保证光合面积,而且还可改善群体内部的光照条件,从而提高群体的光合能力和经济产量。     

盘锦地区稻米品质与灌浆期光合速率相关性研究

以2010年辽宁省盐碱地研究所试验点省区试中晚熟组部分水稻品种为试材,测定稻米品质及水稻群体光合速率,结果表明：水稻品种间稻米品质及群体光合速率均存在差异,齐穗后14 d左右时水稻群体光合速率与稻米的垩白粒率、垩白度呈显著或极显著正相关。     

苦碟子光合作用日变化及其与环境因子关系的研究

本文对苦碟子叶片净光合速率日变化及其与环境因子的相互关系进行了研究,为苦碟子栽培提供参考。结果表明：苦碟子净光合速率日变化呈明显的双峰曲线,峰值出现在上午10时和下午14时,分别为16．82,14．33μmol／m2／s,有轻微的光合“午休”现象。经相关性分析,净光合速率与光合有效辐射、蒸腾速率、气孔导度之间呈正相关,与胞间CO2浓度呈负相关,与空气相对湿度的相关性不显著。     

夏大豆群体光合特性的研究

本文研究了夏大豆的群体光合特性。结果表明，夏大豆群体内光强自上而下逐渐减弱，群体光合随光减弱而明显下降。开花结荚期一天中，１３时群体光合速率达最大值。在一定范围内，密度大的光合速率在上午上升得快，峰值持续的时间长，对早，晚的弱光利用率较高。音以前和１９时以后，各群体的光合速率均为负值。分枝期的群体光合速率主要决定于种植密度。开花结荚期的群体光合速率与种植密度呈抛物线关系，与百粒重，生物产量和籽粒产     

高产冬小麦不同分蘖成穗类型品种群体光合能力的研究

用Ｌｉ－６２００光合测定仪对高产冬小麦两种不同分蘖成类型穗类型的６个品种群体光合速率进行了测定,结果表明,两类型小麦群体光速速率变化基本 全生育期内各体光速速率变化呈单峰型曲线,至挑旗达最大值。小麦生长前、中期群体大小是决定光合能力的关键因素,开花期以后群体大小的影响逐渐变小,灌浆后期落黄好的品种群体光速率高,反之则较低,小麦各体光合速率与叶面积系数、地上部干物质积累量和籽粒产量呈正相关。证明建立     

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).