Parasitisme chez la vigne et consequences oenologiques

Sans résumé     

Sur quelques huiles essentielles nouvelles ou peu connues

Conclusions Douze essences sont étudiées, l'une, connue, celle de Vergerette du Canada et les autres, nouvelles. Les constituants principaux sont des terpènes, sauf pourNepeta mussini (alcool) etScrophularia lucida (cétone). Le terpène dominant, surtout dans les huiles essentielles de Composées, est l'-pinène droit; dans cette famille botanique, j'ai relevé deux fois (Phagnalon sordidum etCota tinctoria), la présence d'un sesquiterpène azulénogène, tel qu'on les trouve surtout dans l'absolue de Camomille romaine. L'acide valérianique, le plus souvent sous la forme combinée, est d'occurrence à peu près constante.Les méthyl-heptyl-cétone et méthyl-nonyl-cétone qui n'avaient guère été signalées que dans les essences de Rue ont été détectées, la première chezScrophularia lucida, la seconde chezAristolochia clematitis, plantes aussi éloignées botaniquement qu'elles le sont, l'une et l'autre, desRuta. Dans deux huiles essentielles, j'ai indiqué l'abondance de paraffines et, dans l'une d'elles, conjointement, celle de résines.

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On some new or less known essential oils

Summary The author gives the chemical and physical characteristics of the essential oils in the following plants:Erigeron canadensis, Phagnalon sordidum, Pulicaria dysenterica, Filaga spathulata, Achillea ageratum, Cota (Anthemis) tinctoria, Senecio erucifolius, Catanche coerulea, Salvia grahami. Nepeta mussini, Scrophularia lucida, Aristolochia clematitis. With the exception ofNepeta mussini (alcohol) andScrophularia lucida (cétone) terpenes are theprincipal constituents. The dominating terpene in the essential oils of the Compositae is the right pinene. Twice in this family, inPhagnalon sordidum and inCota tinctoria, the presence of a sesquiterpene, the azulogenene, has been proved, as it has been found specially in the Roman camomile. The valeric acid, mostly combined occurs nearly always. The methyl-heptyl-cetone and the methyl-nonyl-cetone which have been found until now only inRuta, were found, the former inScrophularia lucida and the latter inAristolochia. In two essential oils paraffines have been found abundantly in one of them, moreover the occurrence of resins has been proved.

     

Le genrePolygonum L. (Polygonacées)

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Radiotherapy of Metastatic Seminoma in the Dog Case Reports

Four dogs with metastatic seminoma were treated with cesium 137 teleradiotherapy. Minimum total tumor dose ranged from 17 to 40 gray (Gy) and was usually given through bilateral opposing sublumbar ports in eight to ten fractions, with three fractions given weekly. The tumor regressed in all four dogs. The first dog (case 1) was free of tumor and died of non-tumor related causes at 57 months. The second dog (case 2) was free of tumor but was euthanatized at 37 months for a limb fracture. The third dog (case 3) was euthanatized for undertermined pulmonary disease 43 months after radiotherapy. The fourth dog (case 4) was euthanatized 6 months following radiotherapy because of transitional cell carcinoma and renal failure. No evidence of seminoma was found at necropsy. Radiotherapy was shown to be effective treatment for seminoma with regional metastasis.     

Towards Commercial Production of Sponge Medicines

Sponges can provide potential drugs against many major world-wide occurring diseases. Despite the high potential of sponge derived drugs no sustainable production method has been developed. Thus far it is not fully understood why, when, where and how these metabolites are produced in sponges. For the near future sea-based sponge culture seems to be the best production method. However, for controlled production in a defined system it is better to develop in vitro production methods, like in vitro sponge culture or even better sponge cell culture, culture methods for symbionts or the transfer of production routes into another host. We still have insufficient information about the background of metabolite production in sponges. Before production methods are developed we should first focus on factors that can induce metabolite production. This could be done in the natural habitat by studying the relation between stress factors (such as predation) and the production of bioactive metabolites. The location of production within the sponge should be identified in order to choose between sponge cell culture and symbiont culture. Alternatively the biosynthetic pathways could be introduced into hosts that can be cultured. For this the biosynthetic pathway of metabolite production should be unraveled, as well as the genes involved. This review discusses the current state of sponge metabolite production and the steps that need to be taken to develop commercial production techniques. The different possible production techniques are also discussed.     

Regeneration of timber trees in a logged tropical forest in North Bolivia

For sustainable forest management, it is important to know the response of timber species to the change in environment caused by logging. We performed a 2-year study on germination, survival and growth of four timber species, Cedrela odorata, Swietenia macrophylla, Hymenaea courbaril, and Cariniana micrantha, and one non-commercial species Tachigali vasquezii. We sowed seeds of these species in five microenvironments: log landing, gap-crown and gap-trunk, skidder trail and understory, in a tropical lowland moist rain forest in northern Bolivia. We related seed and seedling performance to light availability, soil compaction, and plant competition. Germination did not differ significantly between microenvironments but survival of germinated seeds for most species was significantly higher (P < 0.05) in the log landing (46–100%) than in the understory (0–7%). After 2 years, the tallest plants were always found in the log landing (119–190 cm) and the smallest in the understory (12–26 cm) caused by a higher relative height growth rate (RHGR) in the log landing (0.003–0.004 cm cm⁻¹ per day) compared to the understory (0.000–0.001 cm cm⁻¹ per day). During the first year RHGR was positively related to canopy openness for all species and negatively to the number of overtopping competitors for three species. During the second year also water infiltration explained observed variation to RHGR. These results show that abandoned log landings and logging gaps are suitable environments for the regeneration of timber species studied. This finding suggests that the removal of competitors in log landings and logging gaps combined with leaving seed trees near these microenvironments or sowing seeds, will improve regeneration of timber species in tropical forests.     

Chemical characterization of an aqueous extract and the essential oil of Tithonia diversifolia and their biocontrol activity against seed-borne pathogens of rice

Journal of Plant Diseases and Protection - The high cost of chemical pesticides and their negative impact on the environment prompted the search for natural pesticides from plants. The objective of...