Style (botany)
In botany, the style of an angiosperm flower is an organ of variable length that connects the ovary to the stigma. The style does not contain ovules; these are limited to the region of the gynoecium called the "ovary".
Structure
The style is a narrow extension of the ovary, usually pointing upwards, connecting the ovary to the stigmatic papillae. It may be absent in some plants; in this case, it is referred to as a sessile stigma. Styles generally resemble more or less long tubes. The style can be open, featuring a central canal that may be filled with mucilage. Alternatively, the style can be closed. Most plants with syncarpous pistils have open styles, whereas many eudicots and grasses have closed styles containing specialized secretory tissues, which connect the stigma to the center of the ovary. These tissues form a nutrient-rich cord for the growth of the pollen tube.When the pistil consists of several carpels, each of them may have a distinct stylodium or share a common style. In Iris and other species of the Iridaceae family, the style divides into three "petaloid branches", sometimes also called stylodiums, almost at the origin of the style and is called "tribrachiate". These are strips of tissue emerging from the perianth tube above the sepal. The stigma is a ridge or edge on the lower surface of the branch, near the tip of the lobes. Branched styles also appear in the genera Dietes, Pardanthopsis, and in most species of the genus Moraea.
In Crocus species, the style is branched into three "branches," forming a tube. Plants of the genus Hesperantha have a spread-out branched style. The style can also be lobed rather than branched. Plants of the genus Gladiolus have a bilobed style. In the genera Freesia, Lapeirousia, Romulea, Savannosiphon, and Watsonia, the style has bifurcated and curved branches.