香蕉假茎象甲成虫的空间格局研究

香蕉假茎象甲成虫的空间分布规律研究结果表明,香蕉假茎象甲成虫在香蕉园呈较强的聚集分布,平均拥挤度、个体群平均大小随成虫密度增大而增大,个体群所占空间随密度增大而减小;成虫聚集分布主要是由于蕉园环境的异质性引起的。建立了成虫最适理论抽样数公式,提出了为防治决策服务的序贯抽样模型。      

香蕉假茎象甲触角感器的扫描电镜观察

应用日立S-3000N型扫描电镜对香蕉假茎象甲雌、雄成虫的触角形态和感器进行了观察。结果表明:香蕉假茎象甲触角为膝状,由柄节、梗节和鞭节组成。触角表皮普遍具有波浪形刻纹,共有4种感器,即毛形感器、刺形感器、锥形感器和芽孢形感器,其中,毛形感器有3种类型,刺形感器有2种类型。香蕉假茎象甲雌、雄个体间触角感器类型及其分布均无明显差异。触角上的各种感器类型多样,数量众多,分布集中,鞭节上感器最多,梗节次之,柄节无感器。     

香蕉根颈象甲研究进展

香蕉根颈象甲是危害香蕉的重要害虫,在部分地区的留芽蕉园内发生较为严重。本文对国内外香蕉根颈象甲的生物学特性、香蕉根颈象甲的农业防治、化学防治、信息化合物防治及生物防治方面的研究进行了综述,并对其前景进行讨论,旨在为国内开展香蕉根颈象甲的研究和在生产中的防治提供参考。     

红棕象甲成虫对5种植物发酵挥发物的行为反应

利用Y型嗅觉仪测定了红棕象甲(Rhynchophorus ferrugineus)成虫对甘蔗(Saccharum officinarum)、椰子(Cocos nucifera)、假槟榔(Archontophoehix alexandra)、槟榔(Areca catechu)和菠萝(Ananas comosus)等5种植物发酵挥发物的选择行为.结果表明,红棕象甲成虫对不同植物发酵挥发物敏感性不同,对寄主植物的选择性显著高于非寄主植物菠萝,依次排序:甘蔗≈椰子>假槟榔≈槟榔>菠萝.雌成虫和雄成虫对椰子和甘蔗的行为反应同其他3种植物相比有更强的趋性,但雄成虫对假槟榔、槟榔和菠萝3种植物发酵挥发物的选择性无显著差异.甘蔗、椰子、假槟榔3种植物食物诱饵的田间诱捕试验结果表明,植物挥发物对红棕象甲聚集信息素具有极显著的增效作用(P<0.01).3种植物田间诱捕效果差异显著(P<0.05),依次为:甘蔗>椰子>假槟榔.不同食物诱饵诱捕的雌成虫数均多于雄成虫.     

威廉斯香蕉果实膨大期矿质元素累积与分配特征分析

以威廉斯8818香蕉为试材,采用整株挖掘、分解取样的方法,研究其干物质的构成特点、各器官矿质元素含量和累积及分布特征。结果表明,香蕉植株果实膨大期总干物质量为5.4 kg/株,其中叶片占36.1%,假茎占34.3%,球茎占15.1%,果实占10.6%,根占2.9%,果轴占1.1%。每株累积吸收N 61.65 g、P 4.40 g、K 49.65 g,N、P、K的吸收比例为1∶0.07∶0.81。此时期,N、P、K分配率规律为叶片＞假茎＞果实,果轴中则最低。叶片中N含量最高,其次为果实和果轴,假茎(叶鞘)最低。P以果实含量最高,叶片次之,球茎最低。K以果实含量最高,根次之,假茎(叶鞘)和球茎最低。叶片、假茎(叶鞘)、真茎(地上茎)和球茎中各矿质元素含量的大小顺序为N＞K＞P,而果实、果轴和根中则为K＞N＞P。     

LED光质对香蕉组培苗生长的影响

以“巴西蕉”组培生根苗为材料，研究不同LED光质处理对香蕉组培生根苗生长指标的影响，筛选适合香蕉组培育苗的光源方案。结果表明，蓝光（B）处理香蕉组培苗假茎粗度、植株干重显著高于其他处理；红光（R）、黄光（Y）对香蕉组培苗株高有促进作用；绿光（G）处理抑制香蕉组培苗生长；复合光质条件下，红光:蓝光=3:1(R3B1)处理在株高、茎粗、根数、鲜重等指标上均显著高于对照白光（W），可有效促进香蕉组培苗的生长，明显改善香蕉组培苗的生长状况，有利于香蕉组培苗的生长。     

香蕉新株系"热蕉1号"生物学特性研究初报

香蕉新株系"热蕉1号"来源于台湾北蕉的田间芽变体,报道其在香蕉种质资源圃所表现的生物学特性.研究结果表明:在第一茬果假茎高度、围度和巴西蕉相近而高于北蕉,单株产量比巴西蕉和北蕉都高.在第二茬果,"热蕉1号"的假茎高度、围度和单株产量都比其他二个品系高.整体株型表现为茎杆高、叶片宽大较紧密,果型外观整齐、大小适宜,果实主要营养成分指标含量也高,内在品质较好.     

补充营养对茶银尺蠖成虫寿命和产卵量的影响

茶银尺蠖[Scopula subpunctaria (Herrich-Schaeffer)]是危害茶树的常见害虫之一。为了更好地在实验室内饲养此害虫,获得大量供试虫源,研究了补充不同营养对茶银尺蠖成虫寿命和产卵量的影响。结果表明,成虫补充10%蜂蜜水和10%糖水时,雌成虫平均单雌产卵量显著提高,分别为(152.5±16.83)粒和(177.5±19.01)粒;产卵期显著延长,分别为(17.8±1.08) d和(21.4±1.27) d。补充不同营养对雌成虫产卵期和产卵后期有显著影响,但对产卵前期影响不显著。补充10%糖水时,雌成虫的寿命最长,为(29.1±1.41) d,显著高于其他处理;而在10%蜂蜜水、水和对照处理下,雌成虫寿命分别为(23.8±1.15)、(14.4±0.48)、(6.3±0.37) d。补充10%糖水和10%蜂蜜水时,雄成虫的寿命分别为(21.3±0.93) d和(19.5±1.20) d,显著高于水和空白对照处理。在每个处理下,雌成虫的寿命均高于雄成虫。综上所述,10%糖水可作为成虫补充营养的最佳选择。     

不同供氮水平下加硅对香蕉生长与氮营养的影响

采用砂培方法,探讨在正常供氮(200mg/L)和高供氮条件下(400mg/L)加硅对3个香蕉品种生长与氮营养的影响。结果表明:正常供氮和高供氮条件下加硅显著影响3个香蕉品种的生物量、根系活力、硝态氮含量、全氮与硅含量,显著影响氮、硅在根系与地上部分的分配比例,不同品种香蕉响应特征不同,香蕉硅氮代谢相互影响。加硅对宝岛蕉和威廉斯蕉地上部分生物量或根系生物量在2个供氮水平间的变化规律影响不显著,加硅降低或提高这种变化程度。巴西蕉在正常供氮条件下、宝岛蕉和威廉斯蕉在高供氮条件下,加硅提高根系活力,分别较对照提高46.0%、38.4%和1.86倍;加硅降低巴西蕉根系氮与叶片氮含量比例,宝岛蕉、威廉斯蕉在正常供氮条件下加硅提高根系中氮/假茎氮含量比例;加硅显著提高香蕉叶片硅含量,较对照提高17.6%～102.3%;加硅对根系和假茎硅含量影响分别与供氮水平与香蕉品种有关;高氮不加硅条件下,根系中硅含量与氮含量呈显著正相关。     

海南香蕉根颈象甲卵的空间分布型及理论抽样数确定

香蕉根颈象甲[Cosmopolites sordidus(Gemar)1已在海南香蕉园发生,对香蕉生产造成危害.为了研究香蕉象甲的分布和发生规律、指导田间取样,应用几种聚集度指标的计算公式以及Taylor幂法则、Iwao的m*-m回归分析法,分析和测定了香蕉根颈象甲卵的空间分布格局和田间理论抽样数.结果表明:海南香蕉根颈象甲卵在一定密度下呈聚集分布,空间分布符合负二项分布;聚集度指标,I>0,m*/m>1,C>1,Cα>0;Tavlor幂模型表明香蕉根茎象甲卵在一定密度下的分布为聚集的,而且聚集强度随种群密度的上升而升高:Iwao的m*-m回归模型分析表明,m*和m呈显著相关,香蕉根茎象甲个体间相互吸引,最适抽样数n与卵密度m及相对误差D的关系为:n=1/D2(1.3717/m+0.046 3).     

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).