Plant & Animal Genome IX Conference

Poster: Large Insert Libraries, Gene Isolation, Etc.
P02_24.html

GENETIC MANIPULATION OF FLOWERING IN FORAGE GRASSES

Forage Biotechnology Group, The Samuel Roberts Noble Foundation, 2510 Sam Noble Parkway, Ardmore, OK 73401, USA

The nutritive value of forage grasses declines when the less digestible stems and floral organs are formed upon flowering. In order to improve nutritive quality of grasses for better cattle production, a project aimed at delaying the time of flowering in forage grasses was initiated. Annual ryegrass was chosen as a model system for the study due to its relatively shorter life cycle and no vernalization requirement. A cDNA library was constructed from floral meristems of Lolium multiflorum. Since it has been shown that flower-meristem-identity genes such as Leafy plays an important role for acquiring a floral fate in Arabidopsis, similar genes are being isolated from annual ryegrass. A DNA fragment of ~235 bp was obtained from L. multiflorum by RT-PCR and used as a probe to screening the floral meristem cDNA library. Three positive clones were isolated that all showed the highest identities to the RFL gene, a Leafy homologue in rice. The longest insert is ~1.3 Kb and showed 92% identity to RFL. Northern hybridization indicated the gene is strongly expressed in floral meristems of ryegrass. Expression studies of the isolated cDNAs are in progress.