Search results for "botany"
showing 10 items of 4586 documents
Factors affecting shoot proliferation and vitrification inDigitalis obscura cultures
1992
Variations of composition and consistency of the culture medium and time of exposure to growth regulators were assayed to optimize normal caulogenic response ofDigitalis obscura hypocotyls cultured in vitro. The effects of the culture conditions on physiologic changes related to vitrification of the regenerated plants were also investigated. Liquid medium increased the bud-forming capacity of the explants but induced buds failed to develop into shoots and showed symptoms of vitrification. On agar-solidified media, maximum multiplication rates were achieved with 0.7% agar. Increasing agar concentration reduced vitrification but lowered the propagation rate. Changes in the strength of the mac…
Variation of Terpenoids Constituents in Natural Population ofCinnamomum tamala(L.) Leaves
2009
Abstract The leaves of Cinnamomum tamala L. (Lauraceae) were collected from seven plants occurring in seven different areas of Manipur and analyzed for their essential oil and eugenol contents using GC and GC/MS. The yield of the oil was found to vary from 1.5–5.6% (w/w), on a dry weight basis. A total of 79 compounds were identified in the oils. Eugenol was found as a major compound in the leaf oils and its concentration varied from 35.1–94.3% followed by α-phellandrene (1.0–25.4%).
Pythium periplocum, an aggressive mycoparasite of Botrytis cinerea causing the gray mould disease of grape-vine.
1999
Pythium periplocum Dreschler has been found to be an aggressive mycoparasite of Botrytis cinerea, the causal agent of the gray mould disease of the grape-vine. When grown together, the former enters the latter's mycelium, branches freely within, coagulates its cytoplasm and finally tears its hyphae apart, bringing about widespread destruction of the grape-vine pathogen. Extensive coiling around the host, as reported in the case of other mycoparasites belonging to the genus Pythium, has not been observed here. The infected mycelium of B. cinerea fails to infect the grape-vine and does not induce the characteristic gray mould symptoms. Since P. periplocum is not a grape-vine parasite, it coul…
Two new conidial lichenicolous fungi from Spain indicate the distinction ofLichenodiplisandMinutoexcipula
2009
AbstractTwo new conidial lichenicolous fungi are described from Spain:Lichenodiplis crespoaeonCyphelium notarisiiandMinutoexcipula tephromelaeonTephromela atra.Lichenodiplis crespoaediffers from all the described species of the genus in the narrower and shorter conidia, and the hostCyphelium notarisii.Minutoexcipula tephromelaeis characterized by subglobose, conidiogenous cells occasionally bearing 1–2 long proliferating extensions, short conidia and by the hostTephromela atra.
Analysis of pteridines in Pyrrhocoris apterus (L.) (Heteroptera, Pyrrhocoridae) during development and in body-color mutants
1997
By using thin-layer chromatography (TLC) and high-performance liquid chromatography (HPLC), five different pteridines have been quantified in extracts from Pyrrhocoris apterus: neopterin, isoxanthopterin, isoxantholumazine (violapterin), 7-methylxanthopterin, and erythropterin. Biopterin was also detected using HPLC. Pteridines have been analyzed separately in bodies and eyes of the wild type regarding developmental stage and sex. The pteridine content in both bodies and eyes increased from nymphs to 2-day-old adults. After this period, the concentration of pteridines in the eyes of adults remained approximately constant, while in the bodies isoxantholumazine, 7-methylxanthopterin, and isox…
Isolation, culture and plant regeneration from mesophyll protoplasts of Digitalis obscura
1987
High yields of protoplasts were obtained from mesophyll tissue of Digitalis obscura L. Osmotic potential of the isolation medium and Ca2+ were important in obtaining a high viability of the preparations. In different culture techniques employed, liquid-over-agar-solidified medium was superior to liquid medium alone. Agar plating technique was ineffective. On Murashige and Skoog modified medium with casein hydrolysate and several indoleacetic acid and benzyladenine combinations, isolated protoplasts underwent sustained mitotic division and produced calli. The calli formed shoots when transferred to regeneration media. Regenerated shoots could be easily rooted and developed into whole plants …
Differences in the activity and distribution of peroxidases from three different portions of germinating Brassica oleracea seeds
2002
Peroxidase (POD, EC 1.11.1.7) activity, cellular localization and isozyme patterns were investigated in the seed integument, cotyledon and embryo axis of Brassica oleracea cv. Cappuccio during pregermination and seedling growth. Seeds started to germinate after 24 h of imbibition. POD activity was localized in the pigmented layer of the integument and in procambial strands of the cotyledon and embryo axis in the first 24 h of imbibition. It was localized in the integumental cells of palisade, pigmented and aleurone layers and in epidermal, meristematic, procambial cells and xylem elements of the root and hypocotyl after 48 h of imbibition. POD activity increased during germination and early…
Defensive secretions of nymphs and adults of five species of Pyrrhocoridae (Insecta: Heteroptera)
1993
Abstract The chemical composition of the defensive secretions of the nymphs and the adults of Dysdercus fasciatus was investigated. Thirty compounds were identified from the nymphal posterior dorsoabdominal glands, and 34 from the adult metathoracic glands of both sexes. The data were compared with those reported for other species of Pyrrhocoridae. For the species Dysdercus cingulatus, D. fasciatus , and Pyrrhocoris apertus , 63 identified compounds can be divided into 11 chemical groups: aldehydes, saturated hydrocarbons, acetates, alcohols, terpenes, lactones, ketones, esters, alkenes, acids and miscellaneous compounds. These data and those from the literature on Dysdercus intermedius and…
<i>Microcnemum coralloides</i> (Chenopodiaceae- Salicornioideae): an example of intraspecific East-West disjunctions in the Mediterranean…
2008
Kadereit, G. & A.E. Yaprak. 2008. Microcnemum coralloides (Chenopodiaceae-Salicornioideae): an example of intraspecific East-West disjunctions in the Mediterranean region. Anales Jard. Bot. Madrid 65(2): 415-426. Microcnemum is a monotypic genus of Salicornioideae comprising rare, annual, hygrohalophytic herbs growing in hypersaline inland lagoons and salt pans. Microcnemum coralloides shows an East-West disjunction in the Mediterranean region: M. coralloides subsp. coralloides occurs in central and eastern Spain while M. coralloides subsp. anatolicum grows in Turkey, Syria, Armenia and Iran. We studied the phylogeny, biogeography and morphological differentiation of M. coralloides. Molecul…
SOME COMPARATIVE REMARKS ON THE TRANSIENT CHANGE IN LACTIC ACID CONTENT IN SEA URCHIN EGGS FOLLOWING FERTILIZATION.
1964
Abstract During the first few minutes following fertilization a transient increase in the concentration of lactic acid occurs in the eggs of Arbacia lixula , whereas no change at all is observed in the eggs of Paracentrotus liuidus . In the eggs of Psammechinus miliaris there is a transient decrease, soon followed by a recovery so that the level of the unfertilized egg is again reached.