ROANOKE TIMES
Copyright (c) 1996, Roanoke Times
DATE: Thursday, August 15, 1996 TAG: 9608150022
SECTION: CURRENT PAGE: NRV-2 EDITION: NEW RIVER VALLEY
COLUMN: hoein' & growin
SOURCE: DIANE RELF
Pollination is the transfer of pollen from the anther of a plant to the stigma of the same plant (self-pollination) or a different plant of the same species (cross-pollination). Viable or live pollen that lands on a receptive stigma will produce germination as long as the pollen and stigma are compatible. Germination leads to the production of a seed, then usually a fruit forms.
Some fruits and vegetables require cross-pollination before fruit will form, others are self-pollinating. Garden peas and snap beans are self-pollinating with pollen being released at the appropriate time for the opening of the flowers. Tomatoes also are self-pollinating, but need to be shaken to release the pollen into the stigma. This is usually accomplished by wind or insect movement. Other self-pollinating plants are sour cherries, peaches, nectarines and apricots.
Grasses and corn usually are cross-pollinating. They require vectors or movers of pollen, such as wind, insects, birds and even bats. Wind is the primary agent. Plants that are pollinated by the wind tend to have small, inconspicuous flowers. Whereas, flowers that are pollinated by insects usually are brightly colored and scented to attract the insects. Bees are the most common insect pollinators. Other plants requiring vectors are cucumbers, squashes, pumpkins, cantaloupes and watermelons. Raspberries, blackberries and strawberries also benefit by insect pollination.
Compatibility of pollen and stigma can sometimes be a problem with fruit trees. For example, Red Delicious apples must be cross-pollinated with another compatible species, like Golden Delicious, instead of another red delicious tree. This means that Red Delicious trees are self-incompatible. When species are cross-pollinating, interplanting of different species is done to ensure successful pollination and fruiting. Some apple varieties, such as Winesap and Staymen, are not good pollen producers, so they should not be used as pollinators. Other self-incompatible trees are pears, sweet cherries, and European or Japanese plums.
Most gardens have enough bees to accomplish pollination. In some instances, multiple visits from vectors are needed to produce good fruit. For example, cucumber and cantaloupe flowers require at least eight to 12 visits. Symptoms of inadequate pollination are low levels of production and small or misshapen fruit.
LENGTH: Short : 49 linesby CNB