不同基质对中苗期红掌生长及体内氮、磷、钾、钙、镁养分吸收利用的影响

通过不同体积比的粗砂、椰衣、椰糠、花生壳、谷壳的组合对中苗期红掌品种“热情”的处理,研究了不同基质配比对中苗期红掌植株的生长以及N、P、K、Ca、Mg养分吸收利用的影响,结果表明：配方为V椰糠∶V谷壳∶V花生壳＝2∶1∶1的栽培基质其各项理化性状更优,且最有利于中苗期红掌的生长及干物质的积累;中苗期红掌地上部及地下部N、P、K、Ca、Mg的利用率之间无显著规律性,但上述元素的积累量也在配方为V椰糠∶V谷壳∶V花生壳=2∶1∶1的栽培基质上最高。     

不同栽培基质对观赏凤梨‘丹尼斯’营养生长的影响

研究了不同基质配方对观赏凤梨‘丹尼斯’营养生长的影响。结果表明,以体积比为1∶1的椰糠和珍珠岩混合而成的基质对‘丹尼斯’的营养生长最为有利,该基质有利于植株干物质积累,对促进根系的生长及干物质的积累作用尤其明显,同时使植株叶片数增多,株型紧凑、美观。关键词 观赏凤梨 ;花卉 ;栽培基质 ;营养生长     

椰糠替代泥炭作观赏凤梨基质的研究

以奥斯塔拉凤梨为试材,广东泥炭、进口泥炭、蛭石、珍珠岩、海南椰糠为栽培基质材料,按不同比例混合,选用国内外较为通行的改良配方,设定3个营养液浓度进行无土栽培试验.试验以土壤栽培为对照,通过测定基质的物理特性和植株的株高、冠幅、光合速率以及叶片元素(氮、磷、钾、镁、钙、铜、锰)含量,探讨不同基质对奥斯塔拉凤梨生长的影响.结果表明:奥斯塔拉凤梨无土栽培最佳基质配方为:进口泥炭∶蛭石∶珍珠岩=1∶1∶1,而在椰糠∶蛭石∶珍珠岩=1∶1∶1中生长的整齐度最好,可见,椰糠完全可以替代泥炭广泛应用于园艺生产栽培.     

不同基质对秋枫全冠苗生长及生理指标的影响

采用盆栽试验法,研究不同栽培基质对秋枫全冠苗生长和部分生理生化的影响。结果表明:除对照组外,其它3种基质的理化性状差异并不是特别显著;不同基质处理间秋枫叶片的丙二醛、可溶性糖、脯氨酸含量差异不显著,说明四种基质的环境对秋枫苗木的生长来说并不是逆境,秋枫在这四个基质中均可正常生长,是适应性很强的植物。综合胸径和冠幅等表现生长数据和叶绿素、丙二醛、脯氨酸等生理指标,外加基质的理化性状进行分析,基质T2中秋枫的生长状况最好,冠幅最大,叶绿素含量最高。因此,本实验中最适合秋枫生长的基质配比为:泥炭土:椰糠:黄心土:河沙:有机肥=5:1:2:1:1。     

不同基质对闭鞘姜生长发育和光合作用的影响

采用随机区组设计,研究不同配比的红壤、泥炭、椰糠和珍珠岩6种基质配方对闭鞘姜生长的影响。测定6种基质的物理和化学性质,观测萌芽率、叶片数、茎粗、株高、株幅、光合日变化、根茎鲜重和根茎干重。结果显示,基质S4（泥炭+椰糠+珍珠岩=1∶2∶2）的植株净光合速率（P_n）显著高于其他基质处理。在6种基质生长的植株叶片净光合速率曲线呈单峰或双峰变化,而蒸腾速率曲线呈单峰变化。最大株高、最大根茎鲜重和根茎干重也出现在基质S4种植的植株。从以上结果可知,基质S4比较适合闭鞘姜的生长和根状茎干物质积累。     

不同栽培基质对蝴蝶兰矿质营养积累的影响

以蝴蝶兰品种‘内山71’和‘9#’为材料,研究椰糠、泥炭基质栽培下蝴蝶兰品种营养生长及生殖生长时期中叶片、根系的氮、磷、钾及钙、镁、铁的吸收规律。结果表明,椰糠的基质物理性状适合蝴蝶兰栽培。然而,椰糠基质的养分含量不同于泥炭,在生产中需适量增加氮肥和钙肥的供应。蝴蝶兰在生殖生长时期比营养生长时期需要吸收更多的养分,对磷、钾的吸收比率显著升高。2种基质均能生产出商品性状优良的蝴蝶兰,椰糠可替代泥炭进行蝴蝶兰栽培。     

基质与营养液耦合对工业大麻扦插苗生长及产量的影响

为探究温室条件下工业大麻扦插苗栽培的最优基质和营养液配方,进而为工业大麻扦插苗规模化无土栽培提供理论依据。于2021年在长春市农业博览园温室下设置4种栽培基质(泥炭Z1、岩棉Z2、珍珠岩Z3和椰糠Z4)和3种营养液处理(M1、M2、M3),研究栽培基质种类和营养液配方对工业大麻扦插苗营养生长特性、基质温湿度及花叶产量的影响。结果表明,基质和营养液耦合对基质温度无显著影响,基质的湿度为泥炭>椰糠>珍珠岩>岩棉;椰糠+营养液1处理(Z4M1)的工业大麻扦插苗花叶产量、茎粗、植株干物质积累量及开花前后的干物质积累速率均最高。在营养生长期和成熟期,工业大麻扦插苗的干物质积累速率和分配比例均表现为根系最低,茎秆次之,叶片最高。成熟期的工业大麻扦插苗花叶产量与植株干物质积累量、叶绿素含量、叶片含氮量、株高、茎粗和分枝数呈极显著正相关,与土壤温度及土壤湿度无相关性。试验发现,椰糠+营养液1为工业大麻扦插苗温室栽培的最适基质和营养液组合。     

基于椰糠的新型无土栽培基质研究(Ⅱ.) --配方试种筛选

在新型椰糠复合基质研究基础上,通过夏、秋两季作物种植,分别对基质进行配方优化筛选与评价.结果表明：在复合基质配方中,最佳栽培基质配方是椰糠、沙、珍珠岩、污泥的体积比6.75：2：1：0.25,其次是体积比为6.5：2：1：0.5.新型椰糠复合基质盆栽小白菜的鲜重、干重、叶片叶绿素含量、植株含N量以及光合氮效率等指标均高于对照泥炭复合基质配方的,且加营养液供肥方式效果比在基质中一次性加入固体复合肥的供肥方式的好.     

山椒子果实营养成分分析及其种子育苗试验

分析山椒子果实营养成分，并将山椒子种子播种于6种基质[红土、椰糠、河沙、红土＋椰糠(1∶1)、红土＋河沙(1∶1)、河沙＋椰糠(1∶1)]中进行育苗实验。结果表明：山椒子果实所含营养成分丰富，其中果肉和果皮总糖含量分别为14.30%和9.04%，粗纤维含量分别为2.92%和7.12%；检测到17种氨基酸，果肉和果皮中氨基酸总含量分别达1.05%和1.37%；山椒子的最佳育苗基质为红土＋椰糠1∶1基质。山椒子是一种优质野生果树资源，具有重要的引种栽培和开发利用前景。     

不同轻基质配方对油茶全光照扦插生根的影响

以10种轻基质材料为原料配置16种配方,并在全光照间歇喷雾条件下研究这16个配方对普通油茶优良无性系‘岑软3号’扦插生根的影响。结果表明,不同配方轻基质对油茶扦插生根有明显的影响,生根率从6.67%到100%不等,含有椰糠的轻基质配方生根情况明显优于不加入椰糠的配方。在含有椰糠的5种配方中,配方12(椰糠∶菌渣∶泥碳土体积比为4∶2∶1)的生根率最高,达100%,且成本在5个配方中从高到低位列第4,成本较低,最适合作油茶全光照喷雾扦插育苗的基质。     

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).