Pollination

The pollen of a flower contains the genetic material needed for reproduction of the plant. Pollen is made by the male organ of the flower, the stamen. Pollination is the distribution of the pollen to the female organ of the flower, the stigma.

The pollen from the stamen of one flower may be transferred to the stigma of the same flower – self-pollination – or to the stigma of a different flower – cross-pollination.

Very simply, once the stigma has received some pollen, fertilization of the ovules occurs and seed is produced, hence the plant can reproduce.

Plants use water, sunlight, and carbon dioxide from the atmosphere to produce sugars (food) and oxygen: photosynthesis. Life as we know it would not exist without plants. Pollination of plants could be viewed as the necessary ecological process that sustains all life.

Pollen may be transferred from stamen to stigma by gravity, wind, and rain, or by animals – birds, bats, possums, lizards, spiders, and insects. Bees, flies, moths, butterflies, beetles, wasps, ants are just some insect families that are responsible for transferring pollen from one flower to another. It is estimated that 70+% of plants rely on insects for their pollination.

The body of this hoverfly is covered in fine 'pollen-catching' hairs

Plants have evolved various strategies for attracting insect pollinators: by providing pollen and nectar for food; by using fragrances of volatile oils; by using visual clues such as colours and shapes. Some of these strategies are very specific. Some species of flowers, some orchids in particular, are ‘engineered’ to attract just one species of insect.

The long beak and tongue of honeyeaters are suited for reaching the nectar of plants such as grevilleas

The sugar-rich nectar is stored in the nectary, generally deep within the flower, requiring the insect or bird, etc. to scuffle about or to have a long tongue to reach it, ensuring pollen grains are attached to its body.

 

PS: One for the lexophiles (or is it the logophiles?); why is it pollination and not pollenation? Aaaahhh, retirement is fun!