Thursday, November 16, 2006 - 8:45 AM

Molecular and Physiological Characterization of Transgenic, Dwarf Bahiagrass.

Mrinalini Agharkar, U. of Florida/Dept. of Agronomy, McCarty Hall D, Gainesville, FL 32611, United States of America, Fredy Altpeter, Univ. of Florida - IFAS, PO Box 110300, PO Box 110300, Gainesville, FL 32611-0300, United States of America, and Hangning Zhang, University of Florida, 3062, McCarty Hall D, Gainesville, FL 32611.

Bahiagrass is a low input, drought tolerant and disease resistant warm season turfgrass used for residential lawns and along highways in the Southeastern US. Turf quality of bahiagrass is compromised by prolific seedhead production, open growth habit and light green color. The objective of this study was to improve the turf quality of bahiagrass by over-expression of a gibberellin catabolizing enzyme, Gibberellin 2-oxidase (GA2ox).


GA2ox1 and GA2ox8 ORF’s were isolated from Arabidopsis and sub-cloned under the control of the constitutive ubiquitin or 35S promoters. Co-transfer of constitutive nptII and GA-2 oxidase expression cassettes into seed derived callus cultures from turf-type, apomictic bahiagrass (cv. ‘Argentine’) was carried out according to Altpeter and James (2005). Transgenic nature of the regenerated plants was confirmed by NPTII ELISA (Agdia), PCR and RT-PCR.


We will present Northern and Southern blot data showing line specific transgene intergration and expression. The physiological data obtained under controlled environment conditions of soil or hydroponics grown plants allowed us to identify transgenic bahiagrass lines with a superior phenotype. These transgenic lines will be further analyzed under field conditions at the PSREU near Citra, FL.