Somatic Embryogenesis in Woody Plants

The quality of human life has been maintained and enhanced for generations by the use of trees and their products. In recent years, ever rising human population growth has put a tremendous pressure on trees and tree products; growing awareness of the potential of previously unexploited tree resources; and environ- mental pollution have both accelerated the development of new technologies for tree propagation, breeding and improvement. Biotechnology of trees may be the answer to solve the problems which can not be solved by conventional breeding methods. The combination of biotechnology and conventional methods such as plant propagation and breeding may be a novel approach to improving and multiplying a large number of the trees and woody plants. So far, plant tissue culture technology has largely been exploited by commercial companies in propagation of ornamentals, especially foliage house plants. Gene- rally, tissue culture of woody plants has been recalcitrant. However, limited success has been achieved in tissue culture of angiosperm and gymnosperm woody plants. A number of recent reports on somatic embryogenesis in woody plants such as Norway spruce (Picea abies), Loblolly pine (Pinus taedb), Sandalwood (Santalum album), Citrus, mango (Mangifera indica), etc. , offer a ray of hope of: a) inexpensive clonal propagation for large-scale production of plants or 'emblings' or somatic seedlings; b) protoplast work; c) cryopreservation; d) genetic transformation; and e) synthetic or artificial or manufactured seed production.