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This study deals with the wood of Marsdenia erecta R. Br., which is poorly known from a wood anatomical point of view. M. erecta, a woody-based perennial with numerous herbaceous sprawling stems, is distributed in the south and eastern parts of the Balkan Peninsula (incl. Crete)and Asia Minor to Afghanistan. The study aims at describing the wood anatomy of the species in detail based on IAWA list of microscopic features for hardwood identification, and at determining whether it has paedomorphic wood anatomical features. In M. erecta wood, the typical decreasing age-on-length graphic for vessel elements and exclusively upright and square ray cells provide strong arguments for paedomorphosis and secondary woodiness. However, to make a precise decision, this result based on wood anatomy should be checked with molecular phylogenetic data of the species investigated.
Callus cultures of Tabernaemontana persicariaefolia, (Apocynaceae), an endangered species endemic to the Mascarene Islands, were established from leaf explants on MS medium containing either 5 mg·l⁻¹ 2,4-D and 0.5 mg·l⁻¹ BA or 5 mg·l⁻¹ 2,4-D, 0.5 mg·l⁻¹ BA and 200 mg·l⁻¹ DFMO. Histological studies showed regenerating nodules resembling globular embryos in calli after 4 weeks on the DFMO medium. Green shoot formation was achieved by sequential subculture of the induced calli on media with gradually decreasing 2,4-D concentrations (5→1→0 mg·l⁻¹). Regeneration was greatly stimulated in the presence of DFMO. The first emergence of shoots occured 3 weeks earlier than in untreated callus cultures.
Z hodowanej in vitro tkanki kalusowej Holarrhena antidysenterica (Roxb.) Wall. (Apocynaceae) wyizolowano frakcje polisacharydowe A i B, z wydajnością równą odpowiednio 5,76% i 0,74%. Zawartość cukrów w obu frakcjach jest stosunkowo wysoka i wynosi 34% (dla frakcji A) oraz 37% (dla frakcji B). Wyizolowane frakcje zawierają kwasy nukleinowe i komponent białkowy. Analiza chromatograficzna (PC, TLC) produktów kwasowej hydrolizy frakcji polisacharydowych wykazała, że obie frakcje są heteropolisacharydami, zawierającymi te same cukry, arabinozę i glukozę. Obie frakcje zawierają jakościowo ten sam zespół aminokwasów: alaninę, glicynę, kwas asparaginowy, serynę i treoninę.
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Catharanthus roseus G. Don. (CR) or periwinkle plants are widely grown/cultivated as garden plants in the tropics and subtropics. In spite of its predominantly entomophilous nature, CR pollen had been reported to be airborne and allergenic. The objective of this study was to discover the seasonal changes of CR pollen concentration in air, to determine its potential to cause respiratory allergy and to analyze its allergenic components. A 2-year aerobiological survey was conducted with a Burkard 7-day sampler in an agricultural farm in the suburban zone of Calcutta city where CR pollen was found to be almost perennial with 3.6-5.4% contribution to the aeropollen load. Skin prick test was conducted on 282 respiratory allergic individuals living within a 15 km radius of the study area. 29.8% of them were positive to CR pollen. Among them, 80.9% were directly involved in gardening. The whole pollen extract was subjected to gel fi ltration in a Sephacryl S-200 column. Among 5 eluted fractions, fraction I showed optimum IgE-reactivity in ELISA-inhibition. The fraction I shows 4 protein components in SDS-PAGE, within which 3 (40-66 kD molecular mass) were found to be IgE-reactive in immunoblotting using patient sera. It can be concluded that CR pollen can trigger IgEmediated respiratory allergy in the people living in close proximity.
Several years' studies on germination of Catharanthus roseus seeds (Apocynaceae family) are presented. It was found that in Polish climate conditions the hydroponie cultures in the greenhouses are the best method of Catharanthus roseus seed cultures. In these conditions the plants develope and blossom well and abundantly set seeds. The conditions of laboratory estimation were established. Periodical, every month studies of germination ability of seeds from several years showed that in the first year after crop the seeds germinate very well (90-100%). Vitality of seeds keeping in paper bags in the room temperature is al the same level during the following 3 years. In the next years (4 and 5) it depends on weather in the year in which the seeds were set. The seeds maintained the germination ability at the same level or they decreased it even to 35%. Only the seeds keeping in the freeze (-10°C) lose their vitality after 3 years.
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