芦笋组织培养快繁技术

[目的]探索芦笋的组织培养快繁技术.[方法]利用丰岛芦笋3—4月抽出的嫩茎为外植体,在不同培养基上诱导、增殖和生根.[结果]筛选出芦笋适宜的诱导培养基为MS+1.0 mg/L BA+0.1 mg/L NAA,增殖培养基为MS+0.5 mg/L BA+0.1 mg/L NAA,生根培养基为MS+1.0 mg/L IBA+...     

樱桃砧木吉塞拉6号快繁体系建立

[目的]建立樱桃砧木吉塞拉6号快速繁殖体系。[方法]以甜樱桃吉塞拉6号带腋芽茎段为外植体,探讨其在不同激素组合的培养基上的诱导效果及生根培养效果。[结果]适宜的芽诱导与增殖培养基为MS+6BA 1.0 mg/L+IBA0.1 mg/L+NAA 0.1 mg/L,分化率及增殖倍数可达92%和3.4,适合吉塞拉6号组培苗壮苗的培养基为MS+6BA 1.0 mg/L+IBA 0.05 mg/L+NAA 0.05 mg/L,适宜的生根培养基为1/2 MS+IAA 0.5 mg/L+IBA 0.5 mg/L+活性炭0.5 g/L。[结论]在促进吉塞拉6号的分化方面,6BA、IBA和NAA的共同作用优于6BA和IBA组合。     

“罗宾娜”百合组培快繁体系的建立

以OT百合新品种"罗宾娜"(Robina)的种球鳞片为外植体,开展其组培快繁体系的研究。结果表明,鳞片诱导的最适培养基为:MS+6-BA2.0mg/L+NAA0.5 mg/L,其诱导率达到95.83%;采用分切再生小鳞茎的鳞片叶来扩大增殖,增殖培养基为MS+6-BA0.5 mg/L+NAA0.1 mg/L+2,4-D 0.1 mg/L,平均增殖倍数达6.8;生根培养基为MS+6-BA0.5 mg/L+NAA0.1 mg/L+IAA0.25 mg/L,生根率为96.37%;移栽成活率达97.63%以上。     

彩椒的离体快繁研究

以红盾彩椒为试材,进行组培快繁,研究不同激素类型与配比组合对愈伤组织诱导、不定芽分化及芽的伸长的影响,并初步建立彩椒的组培快繁体系。 结果表明：子叶愈伤诱导最适培养基为：MS＋0.3 mg/L 6-BA＋1.0 mg/L NAA;不定芽诱导最适培养基为：MS＋3.0 mg/L 6-BA＋0.5 mg/L IAA＋4.0 mg/L AgNO3;芽伸长最适培养基为：MS＋2.0 mg/L 6-BA＋0.2 mg/L IAA＋2.0 mg/L ZT＋2.0 mg/L GA3;最后在1/2MS＋0.5 mg/L IBA(或 0.5 mg/L NAA)培养基上进行生根培养。     

麻竹组培苗的生根与移栽技术研究

以麻竹(Dendrocalamus latiflorus Munro)组培增殖苗为材料,探索麻竹生根培养基及关键技术,筛选移栽介质。结果表明：诱导生根时,切取高为2～3 cm的丛芽最好,最佳生根培养基为1/2 MS＋IBA 3.0 mg/L＋NAA 0.8 mg/L,生根率达94.6%;麻竹生根苗移栽最佳的基质是椰糠,成活率可达90%,且幼苗生长健壮。     

蜻蜓凤梨叶片组织培养植株再生的研究

以蜻蜓凤梨试管苗叶片为外植体进行离体再生研究。结果表明，叶片诱导直接分化不定芽的最佳培养基是MS＋BA 5.0 mg/L＋IBA 1.5 mg/L，分化率高达80%。增殖培养基为MS＋BA 0.5 mg/L＋NAA 0.2 mg/L。壮苗培养基为MS＋NAA 2.0 mg/L。生根培养基为MS＋NAA 2.0 mg/L＋AC 0.5 g/L，生根率达100%。     

鼓槌石斛组培快繁技术体系研究

以鼓槌石斛八成熟蒴果为外植体,通过对其种子无菌萌发培养、原球茎继代增殖及生根壮苗培养基的筛选,建立鼓槌石斛的组培快繁技术体系。结果表明：1/2 MS＋1.0 mg/L NAA＋8.0%土豆泥＋0.10%活性炭培养基效果较理想,种子萌发率较高,发芽快;最适增殖培养基为3/4 MS+3.0 mg/L 6-BA＋8%香蕉泥,增殖系数可达7.23;最佳生根培养基为3/4 MS＋1.0 mg/L NAA＋0.5 mg/L CA＋8%香蕉泥,平均根数量达7.49条。炼苗移栽到松树皮作为栽培基质的苗床上,1个月以后,成活率均达80%。     

猫尾射的组织培养

以猫尾射无菌播种苗(去除根部)为外殖体,对其愈伤组织诱导和分化及其不定芽增殖进行研究。结果表明,外殖体在MS＋6-BA 1.0 mg/L＋NAA 0.1 mg/L培养基上,愈伤组织诱导和分化的效果较好,愈伤诱导率为82.0%,分化率为74.5%;经不定芽增殖培养基MS＋6-BA 0.5 mg/L＋NAA 0.05 mg/L培养,不定芽增殖倍数为8.2,平均株高为4.7cm。组培苗在MS＋IBA 0.5 mg/L培养基上生根率达90%。生根苗移栽成活率达84%。     

黑绒观音莲顶芽培养和快速繁殖

以黑绒观音莲小球茎顶端切段为外植体，进行组织培养与快繁试验。结果显示，在MS培养基中加入较高浓度的6－BA对顶芽和丛生芽的诱导及继代增殖有利：生根培养基可用1／2MS＋6－BA0.3-0.5mg/L NAA0.8-1.0mg/L，生根率达100％。生根苗移栽到混合30％－40％珍珠岩的椰糠中，成活率达95％以上。采用自然变化温光条件下培养有利于瓶苗的生根和生长，提高瓶苗素质及移栽成活率。     

频繁开花高产小桐子组织培养的初步研究

为了奠定频繁开花型高产小桐子的快繁及转基因基础,通过对小桐子茎段腋芽培养、叶片和叶柄愈伤诱导及不定芽分化的不同激素组合培养进行研究。结果表明：适合该高产品种的茎段培养的最佳培养基为MS＋6-BA 0.5 mg/L＋IBA 0.1 mg/L,叶片愈伤诱导及不定芽分化培养基为MS＋6-BA 2.5 mg/L＋IBA 0.5 mg/L,叶柄愈伤诱导及不定芽分化培养基为MS＋6-BA 1.0 mg/L＋IBA 0.2 mg/L,生根培养以1/2MS＋IBA 0.5 mg/L＋AC 0.1%较为适宜。引起小桐子组培苗玻璃化现象的主要原因之一是BA浓度过高;在不定芽的分化培养中,愈伤过多会严重影响不定芽的数量及质量。     

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).