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Impacts of Shading on Flower Formation and Longevity, Leaf Chlorophyll and Growth of Bougainvillea glabra  [PDF]
M. Saifuddin,A.M.B.S. Hossain,O. Normaniza
Asian Journal of Plant Sciences , 2010,
Abstract: Bougainvillea plants were exposed to artificially reduced light intensity to capture different Photosynthetic Photon Flux Density (PPFD), 0% (direct sunlight), 30, 50 and 75% shading and to observe the effects of shading on flower formation and longevity, leaf chlorophyll and sugar content and quality of plants. Plant attained the greatest leaf size with maximum branching when seedlings were grown in 30 and 50% shading, whereas 0% shading showed the lowest value. Growth parameters related to the plant characteristics such as branch initiation, branch growth and potassium content increased under high shading treatments. Plants exposed to 0% shade showed the highest sugar content and the sugar content decreased by increasing shading. The low light intensity that results in decreased sugar and chlorophyll contents may be attributed to the reduction of flower initiation and in turn to the acceleration of flower abscission. In addition, more than 30% shading led to stop up flower initiation completely. Hence, it is suggested that 0% shading can be applied to maintain frequent flower initiation and flower longevity.
Intraspecific Combinations of Flower and Leaf Volatiles Act Together in Attracting Hawkmoth Pollinators  [PDF]
Zsolt Kárpáti, Markus Knaden, Andreas Reinecke, Bill S. Hansson
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0072805
Abstract: Insects pinpoint mates, food and oviposition sites by olfactory cues. Recognizing and localizing a suitable target by olfaction is demanding. Odor sources emit characteristic blends of compounds that have to be identified against an environmentally derived olfactory background. This background, however, does not necessarily disturb the localization of a source. Rather, the contrary. Sex pheromones become more attractive to male moths when being presented against a relevant plant background. Here we asked whether such olfactory coaction also characterizes foraging cues. The tobacco hornworm Manduca sexta feeds on nectar from wild tobacco Nicotiana attenuata and sacred datura Datura wrightii flowers. We tested how leaf-derived volatile blends as a background affect the moths' approach to flower blends. We found coaction when a flower blend was presented against a conspecific leaf volatile background but not when the blend was presented against volatiles emitted by the other host plant or by a non-host plant. Hence, our results reveal a species-specific coaction between flower blend and leaf volatile background. The ability to integrate information from different odor sources on one plant might provide the moth with a fine-grained analysis of food site quality.
Chemical Composition and Antimicrobial Activity of the Essential Oils from the Flower, Leaf, and Stem of Senecio pandurifolius
Nuran Kahriman,Gonca Tosun,Salih Terzio?lu,?engül Alpay Karao?lu
Records of Natural Products , 2011,
Abstract: The essential oils from the fresh flower, leaf, and stem of Senecio pandurifolius (Asteraceae) were isolated by hydrodistillation in a Clevenger-type apparatus, and characterized by GC-FID and GC-MS. A total of forty-five, sixty, and forty-two compounds were identified, constituting over 90.1 %, 88.0%, and 89.0% of oil composition of the flower, leaf, and stem of S. pandurifolius , respectively. The chemical profile reveals the dominance of sesquiterpene hydrocarbons (flower: 42.4%, leaf: 43.4%, stem: 52.3%) . The main components of essential oils own to S. pandurifolius were α- cuprenene (30.7%) in flower, α-- zingiberene (16.1%) in leaf and γ -curcumene (14.9%) in stem. Terpene related compounds were in minor amounts in all parts (flower: 1.4%, leaf: 1.5%, stem: 1.9%) of the S. pandurifolius . Also there was no monoterpene hydrocarbons and oxygenated monoterpenes in the essential oil of the stem. In addition, antimicrobial activities of the essential oils of S. pandurifolius were investigated. The oils showed activity against Gram positive bacteria, mycobacterium and fungi, but not Gram negative bacteria. A high antimycobacterial activity was observed with leaf essential oil, which deserves further investigation to determine its active components.
A Strawberry KNOX Gene Regulates Leaf, Flower and Meristem Architecture  [PDF]
Mithu Chatterjee, Claudia L. Bermudez-Lozano, Maureen A. Clancy, Thomas M. Davis, Kevin M. Folta
PLOS ONE , 2011, DOI: 10.1371/journal.pone.0024752
Abstract: The KNOTTED-LIKE HOMEODOMAIN (KNOX) genes play a central role in maintenance of the shoot apical meristem. They also contribute to the morphology of simple and compound leaves. In this report we characterize the FaKNOX1 gene from strawberry (Fragaria spp.) and demonstrate its function in trasgenic plants. The FaKNOX1 cDNA was isolated from a cultivated strawberry (F.×ananassa) flower EST library. The sequence is most similar to Class I KNOX genes, and was mapped to linkage group VI of the diploid strawberry genome. Unlike most KNOX genes studied, steady-state transcript levels were highest in flowers and fruits. Transcripts were also detected in emerging leaf primordia and the apical dome. Transgenic strawberry plants suppressing or overexpressing FaKNOX1 exhibited conspicuous changes in plant form. The FaKNOX1 RNAi plants presented a dwarfed phenotype with deeply serrated leaflets and exaggerated petiolules. They also exhibited a high level of cellular disorganization of the shoot apical meristem and leaves. Overexpression of FaKNOX1 caused dwarfed stature with wrinkled leaves. These gain- and loss-of-function assays in strawberry functionally demonstrate the contributions of a KNOX domain protein in a rosaceous species.
Chemical constituents and antimicrobial activity of the ethanol extracts obtained from the flower, leaf and stem of Salvia officinalis L.
DRAGAN T. VELICKOVIC,NOVICA V. RANDJELOVIC,MIHAILO S. RISTIC,ANA S. VELICKOVIC
Journal of the Serbian Chemical Society , 2003,
Abstract: In this paper a comparison of the chemical composition and antimicrobial action of the ethanol extracts from the flower, leaf and stem of the herbal species Salvia officinalis L. (Lamiaceae), originating from the southeast region of Serbia was carried out. The chemical composition of the extracts was determined by GC-FID and GC-MS analyses. Manool has the highest level of all the components (9.0 11.1 %). Antimicrobial activity was determined by the diffusion and dilution method, whereby the latter one was modified by use of cellulose discs, and it was applied for the determination of the minimal inhibitory (MIC) and minimal lethal concentrations (MLC). The leaf extract has a stronger antimicrobial activity than those of the flower and stem.
ANTI-DIABETIC EFFECT OF METHANOLIC EXTRACT OF THESPESIA POPULNEA FLOWER AND LEAF IN NORMAL AND ALLOXAN-INDUCED DIABETIC RATS
S Haja Sherief,Moideen K,Sengottuvelu S,T Sivakumar
International Journal of Research in Ayurveda and Pharmacy , 2011,
Abstract: Methanolic extract of Thespesia populnea flower and leaf exhibited significant Anti hyperglycaemic activity in Alloxan–induced diabetic rats. The flower extract of Thespesia populnea has potent anti hyperglycaemic property compared to standard Glibenclamide. Alloxan induced diabetic rats showed significant increase in the level of blood sugar. Oral administration of flower extract and leaf extract at the dose of 400 mg/kg body weight showed the significant decrease (P< 0.01) on blood sugar level in 10 to 15 days of treatment. The possible mechanism by which the plant extract decreases the blood sugar level may be by potentiation of insulin effect either by increasing the pancreatic secretion of insulin from β-cells of islets of langerhans or by increasing the peripheral glucose uptake.
Bone Remodeling, Biomaterials And Technological Applications: Revisiting Basic Concepts  [PDF]
Helena C. Castro, Jose M. Granjeiro, Patrícia C. Salgado, Plínio C. Sathler, Gutemberg G. Alves, Aline M. de Oliveira, Rodrigo C. de Oliveira, M?nica D. C. Maia, Carlos R. Rodrigues, Paulo G. Coelh, Andre Fuly, Lúcio M. Cabral
Journal of Biomaterials and Nanobiotechnology (JBNB) , 2011, DOI: 10.4236/jbnb.2011.23039
Abstract: Presently, several different graft materials are employed in regenerative or corrective bone surgery. However current misconceptions about these biomaterials, their use and risks may compromise their correct application and development. To unveil these misconceptions, this work briefly reviewed concepts about bone remodeling, grafts classification and manufacturing processes, with a special focus on calcium phosphate materials as an example of a current employed biomaterial. Thus a search on the last decade was performed in Medline, LILACS, Scielo and other scientific electronic libraries using as keywords biomaterials, bone remodeling, regeneration, biocompatible materials, hydroxyapatite and therapeutic risks. Our search showed not only an accelerated biotechnological development that brought significant advances to biomaterials use on bone remodeling treatments but also several therapeutic risks that should not be ignored. The biomaterials specificity and limitations to clinical application point to the current need for developing safer products with better interactions with the biological microenvironments.
The dependency analysis of leaf area mathematic simulation, flower bud length, and flower stem length of Strelitzia reginae
鹤望兰叶面积数学模拟、花苞包片长度与花茎长度相关性研究

QIAN Miao-Fen,
钱妙芬

中国生态农业学报 , 2003,
Abstract: Using geometrical graph method and leaf length multipl yi ng width parametric method, the paper simulates the leaf area of Streditzia re ginae.The results show that flower bud length, leaf area, and stem length have preferble sequence dependency.
The determination of hyperoside in the flower and leaf of hawthorn (Crataegus oxycantha and Crataegus monogyna) by the spectrophotometric method  [PDF]
Mihajlovi? Du?anka,Novkovi? Vesna,Bankovi? Vladimir
Hemijska Industrija , 2006, DOI: 10.2298/hemind0604087m
Abstract: The flower and leaf of hawthorn contains many active components, used in the production of pharmaceutical preparations for cardiotonic, anti-hypertonic anti-hypotonic, artherosclerotic, anti-arithmic and anti-anemic groups. According to the ROTTE list (1996), 159 of 1800 pharmaceutical preparations contain components from hawthorn. Due to the remedial action of hyperoside and other flavonoids from hawthorn, their determination is important for the standardization of extract and preparation quality. The extraction of the flavonoids from a mixture of hawthorn (C. oxycantha and C. monogyna) flower and leaf was carried out by percolation with 40% and 70% (v/v) ethanol. In order to determine the content of total flavonoids calculated as hyperoside spectrophotometric method with aluminium(lll) chloride as a colour reagent at 425 nm was applied. The total flavonoid content in the herbal material mixture was 0.483%, in 40% and 70% (v/v) ethanolic liquid extract it was 138 mg/100 cm3 and 157 mg/100 cm, respectively. The extraction degree of total flavonoids with 40% and 70% (v/v) ethanolic solutions was 57.14% and 65.01% respectively. The yield of total flavonoids in the dry extract was 63% in regard to the herbal mixure content.
Photoelectric Characterization of Dye Sensitized Solar Cells Using Natural Dye from Pawpaw Leaf and Flame Tree Flower as Sensitizers  [PDF]
Mohammed Isah Kimpa, Musa Momoh, Kasim Uthman Isah, Hassan Nawawi Yahya, Muhammed Muhammed Ndamitso
Materials Sciences and Applications (MSA) , 2012, DOI: 10.4236/msa.2012.35041
Abstract: Natural dyes from flame tree flower, Pawpaw leaf and their mixtures were used as sensitizers to fabricate dye-sensitized solar cells (DSSC). The photoelectrochemical performance of the Flame tree flower dye extract showed an open-circuit voltage (VOC) of 0.50 V, short-circuit current density (JSC) of 0.668 mA/cm2, a fill factor (FF) of 0.588 and a conversion efficiency of 0.20%. The conversion efficiency of the DSSCs prepared by pawpaw leaf extract was 0.20%, with VOC of 0.50 V; short-circuit current density, JSC of 0.649 mA/cm2 and FF of 0.605. The conversion efficiency for the flame tree flower and pawpaw leaf dye mixture was 0.27%, with VOC of 0.518 V, JSC of 0.744 mA/cm2 and FF of 0.69. Although the conversion efficiencies, Jsc and the Voc of the prepared dye cells were lower than the respective 1.185%, 7.49 mA/cm2 and 0.64V reported for ruthenium, their fill factors (FF) were higher than that of ruthenium (0.497). It was also observed that both the short-circuit current density and the fill factors of the cells were enhanced using mixed dye.
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