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The growth of axillary shoots was initiated on nodal stem segments, excised from aseptically grown seedlings of Gentiana acaulis L., G. cruciata L., G. lutea L. and G. purpurea L. In later subcultures, a basal callus tissue developed on the shoots, giving rise to de novo formed buds. Optimum benzyladenine and indoleacetic acid combinations for shoot development were established. They were slightly different in the four species. From 35-70% of shoots rooted spontaneously, except in G. lutea, in which adventitious roots were induced by applying naphthaleneacetic acid. It was conduded that the four Gentiana species were amenable to propagation in vitro. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   

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A continuous 15 month study of the floral ecology of four syntopic understorey palm species of Genoma was conducted in Amazonian Peru lowland rainforest. The spicate inflorescences of G. macrostachys, G. acaulis and G. gracilis are strictly protandrous and the plants are functionally dioecious. Data suggest that in G. macrostachys and G. acaulis pollination is based on a mimicry system, the pistillate flowers mimicking the staminate ones in colour, shape and scent. Pollen-collecting meliponine bees (Hymenoptera, Apidae, Meliponinae) and pollen-feeding syrphid flies (Diptera, Syrphidae) which visit inflorescences during both sexual stages are the pollinators of G. macrostachys. Geonoma acaulis is pollinated by small pollen-feeding weevils (Coleoptera, Curculionidae, Derelomini) that visit male and female spikes. Additionally, in G. macrostachys another pollinator type, viz. euglossine bees (Hymenoptera, Apidae, Euglossinae), which are attracted and rewarded by both types of flowers may account for long-distance pollination. The palm G. gracilis shows a very distinct pollination system. Although opportunistic insect visitors are attracted to the inflorescences of this species it seems to be mainly anemophilous because pollen becomes powdery during an thesis. The branched inflorescences of G. interrupta are also protandrous, but unlike the other species of Geonoma observed, staminate and pistillate anthesis of individual flowers are, for the most, overlapping. A broad spectrum of visitors is attracted (bees, wasps, flies, and beetles), which all may act as pollinators. Outcrossing is especially encouraged during the purely female phase at the end of the flowering cycle when there are no more staminate flowers in the inflorescence. Effects on the reproductive biology and population structure of different pollination systems and breeding system are discussed.  相似文献   

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The leaf anatomy of Goniothalamus andersonii, G. macrophyllus, G. malayanus and G. velutinus from the peat swamps of Sarawak is compared. Sufficient anatomical differences exist to differentiate the four species. G. velutinus has many points of difference from the other three species and G. macrophyllus is readily identified by the presence of fibre-sclereids in the lamina mesophyll. G. andersonii and G. malayanus are similar to each other, but G. andersonii can be distinguished, in particular by the more pronounced multiple projections of the outer periclinal walls of the epidermal cells and the presence of thick and cutinised outer ends of the anticlinal walls of the epidermal cells.  相似文献   

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《BMJ (Clinical research ed.)》1936,2(3962):1238-1239
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1. Blood samples obtained from 114 animals of three species of the genus Gazella (Gazella dama, Gazella dorcas and Gazella cuvieri) were analyzed from hematology (osmotic fragility, red blood cells morphology and hemoglobin electrophoresis) and biochemical values (glucose-6-phosphate dehydrogenase, pyruvate kinase and glutathione reductase deficiencies and superoxide dismutase activity). 2. Standard methods were used. Hemoglobin polymorphism was found. 3. There was no abnormality in the osmotic fragility and red blood cells morphology. 4. The biochemical results are compared with information from the literature and with the normal human range.  相似文献   

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