PLANT PARENTHOOD

Sex isn't about having fun. It's serious business for fruits and other plants. Their plan is to produce seeds. This will ensure survival of the species for at least another generation. As far as they're concerned there's no such thing as birth control. No plant can afford to be celibate.

It all begins with pollination. Many fruits require cross-pollination with pollen from another plant of the same or a related species. That's why most garden catalogs selling fruit plants will usually list appropriate plants for pollination purposes. In some cases fruit plants may be self-fertile. Still the fruit set will be greater if the plants are cross-pollinated.

Generally most fruit plants rely on insects or other pollinators. Honeybees are the best known example. Other kinds of plants may rely on other organisms to provide valuable pollinating services. These include spiders, ants, moths, butterflies, thrips, gall midges, hummingbirds, and flies.

Bats pollinate some tropical and subtropical fruits like bananas. Certain cacti in the southwest are dependent upon bats to pollinate the flowers and disperse the seeds. No bats-no fruits-it's as simple as that. In some instances small mammals, such as wild gerbils or marsupial mice, are pollinators. I've seen pictures of these little mice just dusted with pollen as they make their way from one flower to another.

For plants the first step is to attract a pollinator. Advertising does this. Big showy flowers or scented blossoms seem to say, "I'm here. I'm here."

To increase the chances of pollination, the plants often offer a reward to the pollinator. Nectar is a payoff that the insects receive in return for carrying the pollen from one flower to another.

For the most part figs are pollinated by a special kind of wasp called fig wasps. Initially when figs were brought to the New World the figs bore no fruits because the special wasp weren't around. This was easy to remedy.

In some cases the plant requires cross-pollination because the male and female blossoms are on different plants. Hollies and kiwi vines are examples. It's also true for the date palm. This fruit presents a very unique situation. Sometime after the date palm was domesticated the original wild dates disappeared. No one knows when, where, or by whom the plants were domesticated. Assuming there are enough male date palm trees around, wind pollination might be adequate. However no date palm grower takes such chances. They prefer to hand pollinate the trees. Even in ancient Egypt this was done. There is a Mesopotamian relief dating from the reign of King Ashurnasirpal (884-860 B.C.) showing two deities hand pollinating a female date tree.

Go To Page: 1 2

Articles in this Topic    Discussions in this Topic