A colorful photostudy for You tonight featuring my Hibiscus Syriacus, commonly known as Althea Tree or Rose of Sharon Shrub. This bush is planted outside of my kitchen window, so I just open up the window to shoot the bees and soon arriving hummingbirds! This flower is identified as single purple with red throat. They only open for one day and close by evening. As there are many buds, I enjoy a long blooming season (till frost). Plants have one objective in their life: to make seed. The flower must be pollinated before it can make seeds. The bees carry pollen on their body from other flowers. As they walk around the inside of the flower, they leave pieces of pollen. This is a very important process for Humans because we eat the fruits of the plants. Your infostudy is on the Pollination Process. My bumblebees will show us how it is done! Enjoy!
Hibiscus syriacus is a species of flowering plant in the family Malvaceae, native to much of Asia (though not, as Linnaeusthought, Syria, in spite of the name he gave it). Common names include Rose of Sharon (especially in North America),rose mallow (United Kingdom) and St Joseph's rod (Italy).
Althaea frutex Hort. ex Mill.
|> 250 species and subspecies|
Bumblebees and people[edit|edit source]
Comments by Charles Darwin
plants and animals, most remote in the scale of nature, are bound together by a web of complex relations. [...] I have [...] reason to believe that humble-bees are indispensable to the fertilisation of the heartsease (Viola tricolor), for other bees do not visit this flower. From experiments which I have tried, I have found that the visits of bees, if not indispensable, are at least highly beneficial to the fertilisation of our clovers; but humble-bees alone visit the common red clover (Trifolium pratense), as other bees cannot reach the nectar. Hence I have very little doubt, that if the whole genus of humble-bees became extinct or very rare in England, the heartsease and red clover would become very rare, or wholly disappear. The number of humble-bees in any district depends in a great degree on the number of field-mice, which destroy their combs and nests; and Mr. H. Newman, who has long attended to the habits of humble-bees, believes that 'more than two thirds of them are thus destroyed all over England.' Now the number of mice is largely dependent, as every one knows, on the number of cats; and Mr. Newman says, 'Near villages and small towns I have found the nests of humble-bees more numerous than elsewhere, which I attribute to the number of cats that destroy the mice.' Hence it is quite credible that the presence of a feline animal in large numbers in a district might determine, through the intervention first of mice and then of bees, the frequency of certain flowers in that district!
- Cross-pollination, also called allogamy, occurs only when pollen is delivered to a flower from a different plant. Plants adapted to outcross or cross-pollinate often have taller stamens than carpels or use other mechanisms to better ensure the spread of pollen to other plants' flowers.
- Self-pollination occurs when pollen from one flower pollinates the same flower or other flowers of the same individual. It is thought to have evolved under conditions when pollinators were not reliable vectors for pollen transport, and is most often seen in short-lived annual species and plants that colonize new locations. Self-pollination may include autogamy, where pollen moves to the female part of the same flower; or geitonogamy, when pollen is transferred to another flower on the same plant. Plants adapted to self-fertilize often have similar stamen and carpel lengths. Plants that can pollinate themselves and produce viable offspring are called self-fertile. Plants that cannot fertilize themselves are called self-sterile, a condition which mandates cross pollination for the production of offspring.
- Cleistogamy: is self-pollination that occurs before the flower opens. The pollen is released from the anther within the flower or the pollen on the anther grows a tube down the style to the ovules. It is a type of sexual breeding, in contrast to asexual systems such as apomixis. Some cleistogamous flowers never open, in contrast to chasmogamousflowers that open and are then pollinated. Cleistogamous flowers by necessity are self-compatible or self-fertile plants. Many plants are self-incompatible, and these two conditions are end points on a continuum.
Pollen vectors[edit|edit source]
Evolution of plant/pollinator interactions