A comparative study of the lectins from the families Amaryllidaceae and Alliaceae reveals many common features: all bind D-mannose exclusively and have similar molecular structures and amino acid compositions. All these lectins contain subunits of M, 11500-14000 which are not linked by disulphide bonds and occur as dimers (in Allium sativum, A. vineale, A. ursinum, A. moly, Narcissus pseudonarc...

Measurements of natural selection in hermaphrodite populations require the analysis of performance through both female and male sex functions. Here, we investigate selection on three floral traits: flower number, flower length, and corona width through both sex functions in natural populations of the tristylous daffodil Narcissus triandrus. Selection through female function was examined in six ...

Plastid DNA has been isolated from many dif­ ferent sources and characterized in terms of bouyant density, base composition, renaturation kinetics, and sedimentation velocity (for references, c f . 1' 2). For many years, however, it was not possible to isolate plastid DNA in a form sufficiently intact to determine its molecular weight by length measure­ ments in electron micrographs. Only recen...

Three new mannose-binding lectins, isolated from daffodil (NPA), amaryllis (HHA), and snowdrop (GNA) bulbs, are capable of precipitating with a linear mannopentaose (Man alpha 1-3Man alpha 1-3Man alpha 1-3Man alpha 1-2Man). NPA and HHA reacted strongly with the mannopentaose whereas GNA gave a precipitate only at concentrations greater than 500 microM. A phosphate group at C-6 of the nonreducin...

The quality of education of a university depends on its teacher’s major strength and their performance. In a country there have several kinds of universities but their standards of educational qualities are not same. A university will be developed and well known around the world by its educational quality which is completely depend on the quality of an instructor’s teaching proficiency and his ...

Narcissus, the daffodil genus, exhibits an unusual diversity of sexual systems, with populations that are monomorphic, dimorphic or trimorphic for style length. Associated with this variation are striking differences among species in floral morphology and pollination biology. This diversity provides an opportunity to investigate the evolution of mating polymorphisms, and to determine how floral...

Carotenoids are essential pigments of the photosynthetic apparatus and an indispensable component of the human diet. In addition to being potent antioxidants, they also provide the vitamin A precursor beta-carotene. In tomato (Solanum lycopersicum) fruits, carotenoids accumulate in specialized plastids, the chromoplasts. How the carotenoid biosynthetic pathway is regulated and what limits total...