Some pollination misconceptions

David R. Hershey dh321 at excite.com
Tue Feb 3 19:19:16 EST 2004



Given the recent discussion of pollination, here's a list of some
misconceptions on the topic.

1. Pollination is often defined as pollen transfer from anther to
stigma but pollination also occurs in gymnosperms.

2. Not all gymnosperms are wind-pollinated. At least some cycads are
pollinated by beetles. Some Gnetum and Ephedra are pollinated by moths.
Therefore, flowers are not necessarily required to attract pollinators.

3. The importance of animal pollination in plant agriculture is
sometimes exaggerated. Most of our staple crops are wind-pollinated
(corn, wheat, rice and other grasses), self-pollinated (soybean) or
require no pollination for production, (potato, banana).

4. Despite what is often shown in commercials for allergy medicines,
large, colorful flowers rarely cause pollen allergies or hayfever
because their pollen is sticky for animal pollination. Wind-pollinated
flowers that cause hayfever include certain grasses, certain deciduous
trees, certain pines and certain others such as ragweeds, pigweeds and
Plantago spp.

5. Self-pollinated plants also sometimes require wind or insects to
provide pollination. Tomato is self-pollinating but is pollinated by
bumblebees that vibrate the flowers. Greenhouse tomato flowers may need
to be vibrated manually to obtain pollination.

6. Pollination with pollen from another plant of the same cultivar or
clone is still self-pollination.

7. Pollination is not always required for fruit production. There are
several cultivated species that often develop parthenocarpic fruits,
such as pineapple, banana, persimmon, apple, citrus, tomato and
cucumber.





  ------------------------------------------------------------------------
Join Excite! - http://www.excite.com
The most personalized portal on the Web!

---



More information about the Plant-ed mailing list