|MadSci Network: Botany|
It is certainly possible to cross breed plants from different genera but it is not something that occurs with great frequency even with human intervention. Cross breeding different genera has been done. For example, crosses between radish (Raphanus sativus) and cabbage (Brassica oleracea) have been made. There has been some success in ultimately getting some fertile offspring. Unfortunately the offspring have been useless since the leaves are like a radish and the roots are like a cabbage (ideally the roots would be like radish and the leaves like cabbage). So, yes, it is possible to do this, but this is more of an exception than a rule. It depends on the plants you are trying to cross breed. Some combinations would be more likely than others. In terms of the complexity of the process, the cross breeding itself is not difficult and can be done by the home gardener. It is a matter of making sure that both plants are flowering. Pollen from the anther of one flower would need to be transferred to the stigma of the other flower. The anther is often though not always yellow. The stigma is in the very center of the flower and represents part of the female reproductive structure in flowering plants. It is best to remove the anthers of the flowers carefully...you have to make sure you do not get any pollen of the flower onto its own stigma. If you do that you will not be doing any cross breeding. Typical gardening books have pictures of flowers and how to make hybrids so you might want to check out those types of books. Sources: Klug and Cummings. 2000. Concepts of Genetics, 6th edition. Prentice Hall David Hershey adds: The family that most easily lends itself to intergeneric hybrids is the Orchid family. Intergeneric orchid hybrids are widely grown. There are dozens of examples of bigeneric orchids, such as x Laeliocattleya (Cattleya x Laelia) and x Brassocattleya (Brassavola x Cattleya ) . The x in front of the genus name is pronounced "hybrid genus." If you want to grow a bigeneric plant, try the common houseplant Botanical Wonder (x Fatshedera lizei) or tree, Leyland Cypress (x Cuppressocyparis leylandii).
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