Search results for "botany"
showing 10 items of 4586 documents
Floral synorganization and its influence on mechanical isolation and autogamy in Marantaceae
2012
The flowers of Marantaceae (∼ 550 species) exhibit a highly derived pollination mechanism within Zingiberales, with a rapid and irreversible style movement based on a close synorganization of different floral parts. Given the complexity of the structure, we assume that little variation is possible if functionality is to be maintained. To test this, we investigated how much floral diversity exists in the clade and whether this diversity potentially influences the breeding system and placement of pollen on the pollinator. Flowers of 66 species covering the five major phylogenetic clades of the family were analysed. All species are similar in their basic flower construction: the fleshy stamino…
Epitypification of Hagaea alsinifolia (Polyycarpon tetraphyllum subsp. Alsinifolium, Caryophyllaceae)
2018
As part of the ongoing studies on the genus Polycarpon Linnaeus (1759: 859, 881) (see e.g., Iamonico 2015a, 2015b, 2015c, Iamonico & Domina 2015), and on the Italian loci classici (see e.g., Peruzzi et al. 2015, Brundu et al. 2015, Domina et al. 2016, Di Gristina et al. 2017, Domina et al. 2017, 2018a, 2018b), we present here a note regarding Hagaea alsinifolia Bivona-Bernardi (1815: 7–8) [currently accepted (see Bartolucci et al. 2018) as Polycarpon tetraphyllum Linnaeus (1759: 881) subsp. alsinifolium (Biv.) Ball (1877: 370)].
A New Polyploid Species of the Genus Tragopogon (Asteraceae, Cichorieae) from Russia
2008
ABSTRACT Tragopogon soltisiorum Mavrodiev (Asteraceae, Cichorieae, Scorzonerinae) is described as a new species. The new species is a tetraploid (2n = 24), ruderal plant with long flowering and fruiting times and differs from the vast majority of Tragopogon L. species in its ability to reproduce vegetatively from adventitious shoots. The new species is known only from southern Russia and is found in two varieties—a typical variety and a new variety latifolius Mavrodiev.
In vitro control of adventitious bud differentiation by inorganic media components in leaves of matureJuniperus oxycedrus
1995
The effects of changes in the concentration of macronutrients on BA-induced caulogenesis from leaves of matureJuniperus oxycedrus cultured on modified Murashige and Skoog or Schenk and Hildebrandt media are reported. The bud-forming capacity of the explants depended mainly on the ratios among the levels of ammonium, nitrate, and potassium. The most favorable media formulations for differentiation of adventitious buds were those with nitrate:potassium, ammonium:potassium, and nitrate:ammonium ratios near 1, around 0.1, and between 9 and 15, respectively. The total ionic strength of the media limited bud induction, but only when a disequilibrium of these ratios was produced.
Ultrastructure and freeze-fracture studies of the thylakoids ofMantoniella squamata (Prasinophyceae)
1988
The ultrastructure and the supramolecular organization of the thylakoids of the small green flagellate,Mantoniella squamata, were examined in thin sections and freeze-fracture preparations. The whole chloroplast is tightly packed with thylakoids, which show a pattern of meandering, branching and/or anastomosing membranes. In freeze-fracture preparations only two fracture-faces can be distinguished: the PF- and the EF-face. The PF-face has a much higher particle density than the EF-face (PF: 4086 particles/μm2; EF: 865 particles/μm2). The EF-face is not as uniform as the PF-face. The areas which are packed with particles probably correspond to closely appressed thylakoid regions or adhesive …
Activity of bacteria strains originaited from sewage sludge against some soil fungi
2004
Abstract The potential biological activity of three bacterial strains against the four phytopathogens was examined. The bacterial strains were originated from sewage sludge water extract and from the humic acid solution obtained from the sewage sludge. The fresh bacteria cultures and filtered culture broth were used. The noncoated sugar beet seeds were coated by soaking for 15 min in the liquid culture of bacteria, then they were sown in the sterilized soil inoculated by one of the following types of soil fungus: Aphanomyces cochlioides L3, Phoma betas PH8, Pythium irregulare PIR4, Rhizoctonia solani Z10-2. The test proved that Bacillus amytoliquefaciens O1 / O3 and Flaviomonas oryzihabitan…
Invertebrates in Fruitbodies of Heterobasidion spp., Infected Picea abies Logs and Adjacent Soil
2021
Heterobasidion spp. pathogenic fungi produce conspicuous fruitbodies on infected wood, which may represent a habitat for a range of organisms, including invertebrates. The aim was to: (i) assess and compare invertebrate diversity in Heterobasidion spp. fruitbodies, infected Picea abies wood and adjacent soil
Lectotypification of the fountain grass Cenchrus setaceus (Poaceae: Paniceae)
2015
The typification of the name Cenchrus setaceus (Forsskål) Morrone (Poaceae) is discussed, and a lectotype is designated. Cenchrus setaceus is native to northeastern Africa, and cultivated as an ornamental plant in some parts of the world. It is an invasive species in a wide range of natural habitats worldwide, competing strongly with the native flora.
Phytotoxic effects of essential oils of Nepeta curviflora Boiss and Nepeta nuda L.subsp. albiflora growing wild in Lebanon
2009
The chemical composition of the essential oils of two Nepeta species collected in Lebanon was studied by means of GC and GC-MS analysis. The essential oil from N. curviflora Boiss. contained high amounts of β-caryophyllene (41.6%), caryophyllene oxide (9.5%), (E)-β-farnesene (6.2%) and (Z)-β-farnesene (4.8%); in the oil from N. nuda L. subsp. albiflora (Boiss.) Gams. collected in Laklouk the main compounds were β-bisabolene (11.8%), pulegone (10.8%), (E,Z)-nepetalactone (8.0%), (E)-β-farnesene (7.1%) and caryophyllene oxide (6.9%), while N. nuda L. subsp. albiflora collected in Tannourine Cedar Forest contained high percentages of hexadecanoic acid (10.1%), β-bisabolene (7.8%), caryophyllen…
Phenolics of Reichardia and their taxonomic implications
1992
Abstract Fifteen compounds have been detected in Reichardia tingitana and R. picroides (nine flavonoids, four cinnamic derivatives and two unidentified non-phenolic compounds). The present study examines the taxonomic implications of these compounds in relation to the morphological and karyological characteristics.