异色瓢虫十九斑变型对豆黄蓟马成虫的捕食功能反应

异色瓢虫十九斑变型是长春地区大豆田中重要的捕食性天敌昆虫之一,为明确这种天敌昆虫对豆黄蓟马成虫的控制作用,在实验室条件下测定了其捕食作用以及密度和种内干扰对其捕食能力的影响。结果表明:异色瓢虫十九斑变型成虫对豆黄蓟马成虫的捕食功能反应符合HollingⅡ方程,回归模型为Na=0.934 6N/(1+0.0339N);异色瓢虫捕食作用受自身密度制约,平均捕食量随自身密度增大而减少,回归模型为A=13.534P~(-0.702 9);异色瓢虫成虫间存在种内干扰,干扰反应回归模型为E=57.218P~(-1.246)。异色瓢虫十九斑变型对豆黄蓟马成虫有较好的捕食作用和控制潜能。     

不同温度下鞍形花蟹蛛亚成蛛对茶尺蠖3日龄幼虫的捕食功能

鞍形花蟹蛛（Xysticus ephippiatus Simon）是茶园害虫的重要捕食性天敌,为了明确它对茶尺蠖（Ectropis obliqua Prout）的控制能力,在20、25、30℃ 3种不同温度条件下,研究了鞍形花蟹蛛亚成蛛对茶尺蠖3日龄（1龄末2龄初）幼虫的捕食反应。结果表明,鞍形花蟹蛛雌蛛和雄蛛对茶尺蠖3日龄幼虫的捕食功能反应均符合HollingⅡ型方程,在相同温度下,捕食量随着猎物密度的增大而增加。在25℃和30℃时,雌虫的捕食上限均为68头;雄虫的捕食上限以30℃时最大,为67头。相同条件下雌、雄蛛之间的捕食量没有明显差别,而温度对鞍形花蟹蛛的捕食量有明显影响。     

白斑猎蛛对假眼小绿叶蝉的捕食作用

假眼小绿叶蝉是茶园的重大害虫之一,白斑猎蛛是假眼小绿叶蝉的重要捕食性天敌之一。室内条件下,白斑猎蛛对假眼小绿叶蝉的捕食作用的研究结果表明,白斑猎蛛对假眼小绿叶蝉具有一定的捕食作用。白斑猎蛛雌、雄蛛对假眼小绿叶蝉成、若虫的功能反应均为Holling型反应,白斑猎蛛对假眼小绿叶蝉控制能力(a/Th)的大小比较关系为:雌蛛对若虫>雄蛛对若虫>雌蛛对成虫>雄蛛对成虫。白斑猎蛛对自身密度的干扰反应可用E=Na/(NP)和E=QP-m拟合,表明白斑猎蛛个体之间具有极显著的相互干扰作用。      

草间小黑蛛对假眼小绿叶蝉捕食作用的研究

在实验室条件下，研究了草间小黑蛛成蛛对不同密度的假眼小绿叶蝉的捕食功能及温度对捕食功能的影响和捕食者自身密度对捕食作用的影响。其功能反应的类型属于ＨｏｌｌｉｎｇⅡ型反应。温度对寻找产应有一定影响，２４℃条件下，处置时间短，捕食率较高。草间小黑蛛对自身密度的寻找效应可用Ｗｅｔｔ型模拟。     

5种杀虫剂亚致死剂量对龟纹瓢虫捕食作用的影响

测定5种杀虫剂亚致死剂量对龟纹瓢虫捕食作用的影响效应,在龙眼角颊木虱同一猎物密度条件下,亚致死剂量处理的龟纹瓢虫对猎物的捕食量显著低于对照组,但是其捕食功能反应模型结构没有改变,均属于HollingⅡ型,只是功能反应模型参数发生了明显的变化,即捕食者对猎物的瞬间攻击率a下降,处理时间Th延长,最大理论捕食量下降。结果表明:杀虫剂亚致死剂量处理对龟纹瓢虫的捕食作用存在明显的不良影响,5种杀虫剂中以吡虫啉对龟纹瓢虫的捕食作用影响最小,氰戊菊酯的影响程度最大。     

草皮逍遥蛛对大豆蚜的捕食功能反应研究

采用室内试验与田间罩笼试验的方法分别测定了草皮逍遥蛛对大豆蚜的捕食功能与田间控害作用。结果表明:草皮逍遥蛛在室内条件下对大豆蚜的捕食功能反应符合Holling-Ⅱ型方程,当蚜蛛比小于100时,草皮逍遥蛛的捕食量随着大豆蚜密度增加而上升,日均最大捕食量为49.2头。在田间罩笼条件下,草皮逍遥蛛的日均最大捕食量为84.4头,当蚜蛛比小于50时,草皮逍遥蛛可以对大豆蚜起到较好的控制作用,当蚜蛛比大于50时,草皮逍遥蛛可以将大豆蚜发生高峰期推迟约3 d。草皮逍遥蛛可以对大豆蚜起到较好的生态调控作用,但是当大豆蚜处于"窝子蜜"阶段和之后的上升期和盛期时,需要有瓢虫等其它天敌存在时才能有效控制蚜虫危害。     

六斑月瓢虫成虫对几种蚜虫捕食作用的研究

六斑月瓢虫是华中、华南地区栖息于蔬菜、果树等作物上的一种重要的食蚜天敌.其成虫能捕食豆蚜、玉米蚜、桃蚜、高售指管蚜和桔二叉蚜等.当5种蚜虫同时存在时,其较喜食桃蚜.在一定的猎物密度范围内,随着猎物密度的增大,其捕食量逐渐增加,两者之间存着密切的相互性.单头成虫对豆蚜、玉米蚜、桃蚜、莴苣指管蚜和桔二叉蚜的日捕食量上限分别为127、141、256、111和233头.当猎物密度不变时,随着捕食者自身密度的增加,其个体日捕食量减小,因而六斑月瓢虫成虫各个体之间在捕食蚜虫的过程中存在相互干扰效应.     

拟小食螨瓢虫成虫对朱砂叶螨捕食作用的研究

拟小食螨瓢虫是一种栖息于木薯上的朱砂叶螨的重要天敌。其成虫能捕食朱砂叶螨的各个虫态,随着猎物密度的增加其捕食量逐渐上升,对朱砂叶螨卵、幼螨、若螨和成螨的日捕食量上限分别为146粒,87、91和11头。当猎物密度不变时,随着拟小食螨瓢虫成虫密度的增加,其捕食量下降。     

异色瓢虫对取食转Bt基因棉花的扶桑绵粉蚧的捕食功能反应

以转Bt基因棉和常规棉为材料,通过室内测定,研究了以转Bt基因棉为食的扶桑绵粉蚧（Phenacoccus solenopsis）对异色瓢虫（Harmonia axyridis）成虫功能反应的影响。结果表明,异色瓢虫对用转Bt基因棉处理的扶桑绵粉蚧的捕食量与常规棉无显著差异,捕食量均随着密度的增加而逐渐增大,捕食功能反应符合Holling-Ⅱ模型。异色瓢虫对用转Bt基因棉处理的扶桑绵粉蚧的日最大捕食量明显大于常规棉,所用处置时间短于常规棉,瞬间攻击率无显著差异。     

条纹蝇虎对灰茶尺蠖幼虫的捕食作用

为明确条纹蝇虎（Plexippus setipes）对灰茶尺蠖（Ectropis grisescens）的防控效果,在室内条件下,开展了条纹蝇虎对灰茶尺蠖幼虫的捕食量、捕食功能反应、捕食选择性和种内干扰效应的研究。结果显示,条纹蝇虎偏好捕食灰茶尺蠖低龄幼虫,不同发育阶段捕食能力存在显著差异;其中成蛛捕食能力最强,日均可捕食灰茶尺蠖1龄幼虫17.44头,幼蛛捕食能力相对较弱,日均捕食1龄幼虫2.33头。条纹蝇虎捕食功能反应符合Holling Ⅱ模型,捕食量随灰茶尺蠖幼虫密度的增加而增加,而搜寻效应逐渐降低。捕食选择性试验表明,条纹蝇虎对灰茶尺蠖1龄幼虫和2龄幼虫表现为正喜好性（Ci>0）,对3龄幼虫表现为负喜好性（Ci<0）。条纹蝇虎对灰茶尺蠖幼虫的捕食作用同时受自身密度的影响,存在较强的种内干扰反应,该反应符合Hasse Ⅱ模型。研究表明,条纹蝇虎对灰茶尺蠖幼虫具有较强的捕食能力和良好的防控潜能,这为利用茶园蜘蛛天敌资源提供理论依据。     

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.