Answer  Hint: The flowers pollinated by the biotic agents reward them with nectar. These flowers are most conspicuous and attract the pollinating agents by scent or bright colors. Complete answer: We will first learn the pollination and the pollinating agents. Flowers are the organs of sexual reproduction in plants. After the formation of male and female gametes by microsporogenesis and megasporogenesis respectively, pollination occurs.During pollination, the pollen grains reach the stigma of the pistil to facilitate fertilization.Here, we should understand that plants can exhibit autogamy, geitonogamy, and xenogamy. In geitonogamy and xenogamy, pollens from the anther are carried to the stigma of the pistil of another flower from the same or different plant, respectively. These two modes of pollination require the agents of pollination to facilitate the transport of pollen grains. Several biotic and abiotic agents help in pollination. Wind, water, and wind are the most common abiotic agents of pollination while insects are the biotic agents. Some examples of wind-pollinated flowers are maize and parthenium while rose and snapdragon are insect-pollinated flowers. The differences between the wind and insect-pollinated flowers are as follows:
Note: Nectar is rich in sugars and serves as an energy source for insects. Since insect-pollinated flowers produce fragrance to attract the pollinators, it should not be taken that all these plants produce sweet-smelling flowers. The odor depends on the pollinators. For example, the flowers pollinated by beetles produce a foul smell.
Many flowers are pollinated without the aid of animals (insect, bird, or mammal). Some are pollinated as the currents of wind or water act as vectors. These flowers do not generally attract animal pollinators. Most conifers and about 12% of the world’s flowering plants are wind-pollinated. Wind pollinated plants include grasses and their cultivated cousins, the cereal crops, many trees, the infamous allergenic ragweeds, and others. All release billions of pollen grains into the air so that a lucky few will hit their targets. Water pollinated plants are aquatic. Pollen floats on the water’s surface drifting until it contacts flowers. This is called surface hydrophily, but is relatively rare (only 2% of pollination is hydrophily). This water-aided pollination occurs in waterweeds and pondweeds. In a very few cases, pollen travels underwater. Most aquatic plants are insect-pollinated, with flowers that emerge from the water into the air.
U.S. Forest Service
United States Department of Agriculture
Many flowers are pollinated without the aid of animals (insect, bird, or mammal). Some are pollinated as the currents of wind or water act as vectors. These flowers do not generally attract animal pollinators. Wind PollinationWind pollinator flowers may be small, no petals, and no special colors, odors, or nectar. These plants produce enormous numbers of small pollen grains. For this reason, wind-pollinated plants may be allergens, but seldom are animal-pollinated plants allergenic. Their stigmas may be large and feathery to catch the pollen grains. Insects may visit them to collect pollen, but usually are ineffective pollinators and exert little natural selection on the flowers. Anemophilous, or wind pollinated flowers, are usually small and inconspicuous, and do not possess a scent or produce nectar. The anthers may produce a large number of pollen grains, while the stamens are generally long and protrude out of flower. There are also examples of ambophilous (pollinated by two different classes of pollinators) flowers which are both wind and insect pollinated.
Most conifers and about 12% of the world’s flowering plants are wind-pollinated. Wind pollinated plants include grasses and their cultivated cousins, the cereal crops, many trees, the infamous allergenic ragweeds, and others. All release billions of pollen grains into the air so that a lucky few will hit their targets. Wind-pollinated flowers are typically:
Water Pollination
Water pollinated plants are aquatic. Pollen floats on the water’s surface drifting until it contacts flowers. This is called surface hydrophily, but is relatively rare (only 2% of pollination is hydrophily). This water-aided pollination occurs in waterweeds and pondweeds. In a very few cases, pollen travels underwater. Most aquatic plants are insect-pollinated, with flowers that emerge from the water into the air. Many of the water-pollinated plants have become invasive throughout the United States. To learn more, visit these invasive species websites:
https://www.fs.usda.gov/wildflowers/pollinators/wind.shtml |
What is the difference between wind pollination and water pollination?
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