In pollen culture, researchers will remove the stamen (male part) of a plant and then use the pollen on the stamen to generate new plants. Pollen is composed of small gametes (reproductive cells). Scientists place these anthers (the part of the stamen that contains pollen) in a container of nutrients in order to stimulate cell division. New plants can be grown using only pollen, which eliminates many of the hassles associated with crossbreeding plants.
Pollen culture is usually used to produce transgenic plants, which contain genes from another species. After the anther is removed and the pollen is isolated, these genes are inserted into individual gametes (pollen grains). Scientists can then culture the pollen by using a growing medium. With traditional techniques, transgenic pollen would have to be inserted into the female part of the flower for natural fertilization. The cross between transgenic gametes and regular gametes can have uncertain effects, which may decrease desired characteristics in a plant. The same uncertainty would apply when crossbreeding two transgenic plants because of genetic variation.
Pollen culture allows scientists to select for desirable characteristics in plants without having to crossbreed two different plants. Researchers may be trying to obtain higher yields, better colors, drought resistance or plants that require less fertilizer. Crops may also be bred to have a natural resistance to a specific pest or to have an increased shelf life. With traditional methods, scientists would have to track the breeding record of plants over multiple generations to try to breed a particular characteristic into a plant strain. When a scientist uses pollen culture, he is using a single gamete from a plant which shows a desired characteristic, meaning that the resulting plant will have a good chance of being homozygous (more likely to show the desired characteristic).
Breeding two plants together requires scientists to brush the pollen off of one plant and then place this pollen on the female parts of another plant. Because the risks of natural cross pollination are high, researchers must use heavily controlled indoor laboratory settings to prevent accidental pollination. Detailed records must be kept of the different characteristics of plants. This process requires a lot of money and effort. With pollen culture, researchers can stimulate the production of plants, using only pollen, with an almost 100 percent success rate without the risk of unintended cross pollination. 1,000 plants can be created using only a single anther, and it takes only 24 hours in a growth medium for plants to start developing.