Search results for "botany"
showing 10 items of 4586 documents
Characterisation of Pythium paroecandrum and its antagonism towards Botrytis cinerea, the causative agent of grey mould disease of grape.
2004
Pythium paroecandrum (B-30), an oomycete, was isolated from soil samples taken from a wheat field in Genlis in the Burgundy region of France and was found to check the growth and development of Botrytis cinerea, a serious grapevine pathogen. The oomycete is a fast-growing organism, living on vegetable debris, and can be recognised by its catenulate hyphal swellings, catenulate oogonia, and monoclinous antheridia. When grown together with B. cinerea, the causal agent of the grey mould disease of the grapevine, P. paroecandrum shows a pronounced antagonism and suppresses its growth and its aptitude to provoke the grey mould symptoms. Morphological features of this oomycete, its antagonism to …
A new mycoparasite, Pythium lycopersicum, isolated in Isparta, Turkey: morphology, molecular characteristics, and its antagonism with phytopathogenic…
2008
Pythium lycopersicum sp. nov. has been isolated from soil samples taken in an agricultural land in the Isparta region of Southern Turkey. This oomycete is characterized by its contiguous sporangia having globose to elongated elements linked with hyphal filaments, ornamented oogonia, and monoclinous antheridia with large antheridial cells. The oomycete is reminiscent of Pythium ornamentatum described by the corresponding author in 1987 from soil samples taken in Algeria. Sequence analyses of the internal transcribed spacer (ITS) regions of rRNA show a close relationship with Pythium oligandrum and other mycoparasites possessing ornamented oogonia. Morphological and molecular features of this…
Chemical variability in the essential oil of Cinnamomum tamala L. leaves from India.
2011
The chemical composition of the essential oils obtained from the fresh leaves of Cinnamomum tamala Nees et Eberm. was determined by GC and GC–MS. The yield of the oil on a dry weight basis ranged from 1.2% to 3.9% (w/w). Phenyl propanoids constitute the major portion (88.9–95.0%) of the oils. Fifty-four compounds were identified from the oils. Eugenol (91.4–41.8%) was the main compound, followed by eugenyl acetate (0.0–47.1%) and α-phellandrene (0.6–2.5%) in the analysed oils.
Non-Botrytis grape-rotting fungi responsible for earthy and moldy off-flavors and mycotoxins
2012
Abstract The grape microflora is complex and includes filamentous fungi, yeasts and bacteria with different physiological characteristics and effects on wine production. Most studies have focused on the wine microbiota, but a few studies have reported the ecology of grape microorganisms. Some of these organisms — such as non-Botrytis bunch rotting fungi, which greatly influence the safety or sensory quality of wine, due to the production of mycotoxins and off-flavors, respectively — are considered to be spoilage agents. We review here the diversity of filamentous fungi on grapes and the factors influencing their development, such as grape ripening stage, environmental factors (climate, rain…
Pythium contiguanum nomen novum (syn. Pythium dreschleri Paul), its antagonism to Botrytis cinerea, ITS1 region of its nuclear ribosomal DNA, and its…
2000
Pythium drechsleri Paul was described as a new species from soil samples taken in a salt-marsh of Arzew, Algeria [Paul, B. (1988) Une nouvelle espece de Pythium isolee d'une saline de l'ouest Algerien. Cryptogam. Mycol. 9, 325-333]. The name of the fungus, P. drechsleri, is a nomen invalidum, as it is a later homonym of P. drechsleri Rajgopalan and Ramakrishnan [Rajagopalan, S. and Ramakrishnan, K. (1971) Phycomycetes in agricultural soils with special reference to the Pythiaceae. Madras Univ. J. Sect. B 37,38, 100-117]. A new name, Pythium contiguanum is now being given to P. drechsleri Paul. This species is characterised by its contiguous inflated type of sporangia, smooth-walled oogonia …
Essential Oil Composition of the Aerial Parts of FiveOcimumspecies from Western India
2015
AbstractChemical composition of the essential oils of five Ocimum species namely Ocimum tenuiflorum syn Ocimum sanctum L. (green and purple), Ocimum kilimandscharicum Guerke, Ocimum viride Willd, Ocimum basilicum L. and Ocimum gratissimum L., obtained by a hydrodistillation was determined by GC and GC-MS. A total of one hundred three compounds were identified in the oils of five Ocimum species, of which fifteen compounds were found to be major (5.0–81.8 %) compounds. Analysis of Ocimum viride oil showed the highest amount of eugenol (81.8 %) among species besides germacrene D (7.0 %) and cis-ocimene (4.1 %). Ocimum tenuiflorum green and Ocimum tenuiflorum purple were found contain eugenol (…
Performance of Host-Races of the Fruit Fly,Tephritis conuraon a Derived Host Plant, the Cabbage ThistleCirsium oleraceum: Implications for the Origin…
2008
The thistle-infesting fruit fly Tephritis conura Loew (Diptera: Tephritidae) forms host races on the melancholy thistle, Cirsium hetewphyllum (L.) Hill (Asterales: Asteraceae) and the cabbage thistle, Cirsium olemceum (L.). Scop. Previous research indicates that the host shift occurred from C. hetewphyllum to C. oleraceum. In this paper we address whether the host shift involved physiological adaptations by studying oviposition acceptance and survival of the two host races on the derived host C. oleraceum. Performance differed significantly between host races. T. conura originating from C. oleraceum produced adults in 75% of all egg-laying trials in contrast to only 6.6% in T. conura origin…
Agronomical and chemical characterisation of Thymbra capitata (L.) Cav. biotypes from Sicily, Italy
2015
In this study the agromomical and chemical characterization of 13 sicilian biotypes of Thymbra capitata (L.) Cav. (or Thymus capitatus Hoff. et Link.) collected from different areas of Sicily (Italy) and grown under the same agricultural and environmental condition are reported. The main morpho-productive parameters and quali-quantitative profile of essential oils were determined . Essential oils were extracts from the aerial parts of the plants by hydrodistillation. The essential oils were analyzed by GC-FID and GC-MS. Hierarchical Cluster Analysis and Principal Component Analysis statistical methods were used to group biotypes according to the essential oils chemical composition. The esse…
Composition and antibacterial activity of the essential oil ofAnisochilus carnosus (Linn. ?l.) Benth., a Tamil plant acclimatized in Sicily
2003
The essential oil from aerial parts of Anisochilus carnosus (Linn. fil.) Benth. (Lamiaceae) was obtained by hydrodistillation. The oil content was 0.13% (v/w), on a fresh weight basis. The oil composition was analysed by GC and GC–MS and 28 compounds were identified, accounting for 94.3% of the oil. Carvacrol (27.9%), camphor (14.1%) and α-cis-bergamotene (10.2%) were the most abundant components. The oil is active against Gram-positive and Gram-negative bacteria. Copyright © 2003 John Wiley & Sons, Ltd.
<p><strong><em>Linaria semialata</em> and <em>L. amethystea </em>subsp.<em> aedoi</em>,<em> <…
2020
Two new taxa of the genus Linaria are described, illustrated and compared, through a morphometric analysis, to morphologically similar species from L. sect. Supinae: L. amethystea, L. diffusa, L. intricata, and L. orbensis. A Principal Component Analysis and Linear Discriminant Analysis were carried out in order to find out which morphological characters were the most important to discriminate these species. Morphometric analyses revealed that discrimination of species were more related to their particular morphological character combinations than to a private character. Two taxa are described as new to science, by providing a detailed description, illustrations, scanning-electron micrograp…