It is becoming increasingly important that support is provided for users who are dealing with complex information spaces. The need is driven by the growing number of domains where there is a requirement for users to understand, navigate and manipulate large sets of computer based data; by the increasing size and complexity of this information and by the pressures to use this information efficie...

Three studies tested the hypotheses that the activation of communal mental representations promotes relationship commitment (communal activation hypothesis) and that this effect is stronger among narcissists than among nonnarcissists (Communal Activation x Narcissism hypothesis). Across experimental, longitudinal, and interaction-based research methods, and in participant samples ranging from c...

Compounds that promoted the growth of pollen tubes were isolated from the style of Rhedodendeon muerenatum and were identified as azalein, (+)-catechin, and (-)epicatechin. Among these compounds, 50-100ppm of (+)-catechin or (-)-epicatechin increased the growth of pollen tubes in thmetlia japoniea, R. mueronatum, Slyrax japoniea, and Pinus densij7bra by 16-20%. These compounds had no significan...

A simple RNA isolation method based on hot borate and proteinase K was used to extract high-quality RNA from petals of daffodils (Narcissus pseudonarcissus L. 'Dutch Master'). The method was adapted from the isolation technique described by Wan and Wilkins (1994). A single isopropanol precipitation and ethanol wash replaced all the second day steps of the Wan and Wilkins procedure. The RNA isol...

Flower senescence is a highly controlled developmental event that culminates in the death of the floral organs. Most research on flower senescence has focused on the perianth, since it typically determines the commercial life of the flower. The mechanism by which the perianth dies differs between species: in some flowers, wilting is the primary symptom of senescence whereas in others, the peria...

PREMISE OF THE STUDY Microsatellite markers were developed using hoop-petticoat daffodils (Narcissus sect. Bulbocodii; Amaryllidaceae) to aid in the taxonomic revision of the section, and to further evaluate their broad applicability for daffodil cultivar identification. METHODS AND RESULTS Three hundred fifty-one primer pairs were developed using a commercial service. Nineteen polymorphic an...

The spatial context of reproduction is of crucial importance to plants because of their sessile habit. Since pollen and seed dispersal is often restricted, mating success is likely to depend on the quantity and quality of mates in local neighbourhoods. Here we use neighbourhood models to investigate the spatial ecology of pollination and mating in Narcissus assoanus, a sexually polymorphic plan...

Although chromoplasts and chloroplasts are mor­ phologically and functionally very different, it has been shown in certain plants and under certain con­ ditions, that they are interconvertible [see 1 5]. One could then expect such plastids to contain, at least qualitatively, the same plastome. It appears questionable, however, whether this applies to all plastid types. For example, FreyWyssling...

Stigma-height dimorphism is a sexual polymorphism in which plant populations are composed of two floral morphs that differ significantly in style length but not anther position. The morphs exhibit approach and reverse herkogamy, floral designs that in most species typically occur as monomorphic conditions. We investigated the floral biology of stigma-height dimorphism in the Mediterranean geoph...