Although only a limited number of potentially useful genes have been tested in tall fescue, many more genes shown to be effective in other species could be evaluated in tall fescue. Examples include genes involved in drought tolerance (Aharoni et al., 2004; Kasuga et al., 1999; Zhang et al., 2005), cold tolerance (Hisano et al., 2004; Jaglo-Ottosen et al., 1998; Kasuga et al., 2004), salt tolerance (Apse et al., 1999; Zhang and Blumwald, 2001), disease resistance (Fu et al., 2005; Takahashi et al., 2005; Xu et al., 2001), forage quality (Li et al., 2003; Piquemal et al., 1998; Reddy et al., 2005), growth and development (Cheng and Wang, 2005; Jensen et al., 2004; Schwab et al., 2005), and nutrient uptake (Richardson et al., 2001; Xiao et al., 2005; Zimmermann et al., 2003). In some cases these genes can be used directly in tall fescue, while in other cases corresponding genes need to be isolated from tall fescue or other closely related grass species, such as ryegrass.

Rapid development of gene sequencing technology has enabled major advances in our ability to gather whole genome-scale information from model plants. While gene isolation has become easier than ever, functional characterization of large numbers of genes has become the bottleneck in grass research. Tissue culture-based methods generally require considerable training of the practitioner to develop the skills needed to generate sufficient numbers of transgenic plants (Somers et al., 2003). Although significant progress has been made in producing transgenic tall fescue, the production of transgenics with more single copy integrations by Agrobacterium-mediated transformation has been fairly recent. There is a great need to improve transformation efficiency in tall fescue and thus allow the production of large numbers of transgenic plants in a shorter time.

Transgenesis provides the most rapid means of introducing truly novel traits to crop plants, and is also a major technology for studying functional genomics in plants (Dixon et al., 2007). The technologies developed for genetic manipulation of tall fescue have opened up new opportunities for molecular breeding of this species. The transgenic approaches deployed for tall fescue can be adapted easily for the improvement of other forage and turf grasses. Integration of transformation technology into applied grass breeding programs is likely to result in the development of landmark cultivars in the twenty-first century.

 

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