Gene transfer in plant s

With the specter of dwindling biotic diversity, need is increased for preservatio n of available germplasm . Plant germplasm may be preserved in a variety of ways including seed storage, cryopreservation, and tissue culture . A new method of germplasm preservatio n may be through the storage of DNA libraries, which maintain in test tubes the genes tha t encode life's diversity . This new area of plant research germinated more than a decade ag o and is beginning to bear fruit today . To be a viable alternative to traditional methods , however, ways must be devised to return cryopreserved genes to living cells, where they can be expressed and utilized to man's benefit . DNA libraries also can be used to increase genetic diversity greatly through methods involving molecular biology and gene transfer . Numerous strategics have been developed to transfer genes into plants . Some of thes e techniques can be used to combine (entire) whole genomes by fusing two plant protoplasts . These somatic hybridization procedures have been refined to allow the combination o f nuclear and organelle genomes from different plant species . Transfer procedures also hav e been developed for moving genes from chloroplasts, mitochondria, or nuclei into alien cytoplasms . Still other techniques can shuttle single genes from one plant species to another . These gene transfer techniques are being developed at a rapid pace to complement equall y rapid developments in gene isolation, cloning, and recombination techniques . A multitude of barriers inhibiting the transfer of genes to plants plagued the agricultura l scientists of the I970 ' s, and many problems face these scientists today . But significan t progress is being made, and further refinements in current plant gene transfer techniques wil l provide a strong base for future crop improvement using biotechnology .