Background and Aims is called an eternal flower and has large,
Background and Aims is called an eternal flower and has large, coloured, scarious bracts. other flowers MHY1485 or leaves. The cells of the bract differ from other tissues with secondary cell walls, suggesting that they may be a new cell type. has compound flowers comprised of many tubular flowers and scarious bracts (Everett, 1980). The scarious bracts are large and coloured like a corolla. They maintain their aesthetic value without wilting or discoloration for many years, even after cutting. is usually, therefore, suitable as a dried flower. Many species in the Compositae family Inurae tribe have such characteristic flowers, including and and have similarly characteristic flowers. The same can be said of and in the Amaranthaceae family and of in the Plumbaginaceae family. In all these plants, the scarious bracts or sepals of their flowers are large and coloured like a corolla, similarly to those in seikounoaki was found to be 885 %, that of the scarious bracts of Jumbo Yellow was 386 %, and that of the scarious sepals of Sundaeviolet MHY1485 was 212 %. Water contents of the leaves of these species were 889 %, 910 % and 759 %, respectively. Thus, scarious tissues have a low water content, while growing herb tissues typically contain 80 to 90 % water. Wood is usually composed mostly of dead cells, and has a low water content. For instance, the sapwood that functions in transport in via the xylem contains 35C75 % water (Taiz and Zeiger, 2002). The scarious bract of is usually composed of dead cells (Troll, 1957). These observations suggest that scarious bracts and scarious sepals are composed of dead cells. However, to the best of our knowledge, no research studies show this, nor are there reports of the cell morphology of scarious bracts and sepals. We investigated whether the cells of the scarious bracts of Monstrosa are dead or alive by observing nuclei of such cells stained by DAPI (4’6-diamidino-2-phenylindol dihydrochloride) under a fluorescence microscope, and examined the morphology of scarious bract cells under a light microscope, a transmission electron microscope and a polarized MHY1485 light microscope. MATERIALS AND METHODS Plants of Monstrosa were cultivated in a plastic greenhouse at Kyoto University in Japan. They were produced in pots made up of the growing medium Metro-Mix 360 (Sun Gro Horticulture Canada Ltd, Seba Beach, Canada) under natural sunlight. The composition of this medium is usually peat moss, vermiculite, bark ash, bark, dolomitic limestone and a wetting agent. The solid fertilizer IBS1 (N : P : K = 1 : 1 : 1; JA Group, Tokyo, Japan) was applied. Flowers of these herb were used in the following experiments. DAPI staining and fluorescence microscopy Seven stages of flower development were considered (Fig.?1A): stage 1, bud <80 mm wide; stage 2, bud 80 10 mm wide; stage 3, bud 10 12 mm wide; stage 4, bud 12 14 mm wide, with its second layers MHY1485 of bracts starting to open; stage 5: 4th 5th bracts of the bud starting to open; stage 6, innermost bracts of the bud starting to open; and stage 7, all bracts completely opened (anthesis). The innermost bracts at each stage of flower development, or bracts adjacent to tubular flowers, were used in the following experiments, which were performed according to Gladish (2006). Bracts at each stage were MUC16 stained with 1 mg LC1 DAPI (4’6-diamidino-2-phenylindol dihydrochloride) MHY1485 in 10 mmol LC1 Tris/HCl buffer (pH 74). The bracts were soaked in DAPI solution in a vacuum pump in the dark overnight to completely stain the nuclei of all cells of the bracts. Nuclei of the bract cells were.