APS Abstracts of Presentations

Transformation of Leptosphaerulina trifolii and its interaction with Medicago
M. R. DHULIPALA (1), J. N. Enis (1), S. Casanova (1), S. M. Marek (1)
(1) Oklahoma State University
Phytopathology 96:S29

Leptosphaerulina trifolii (Rostovzev) Petr. (Ascomycota: Pleosporaceae) causes Lepto leaf spot of alfalfa (Medicago sativa L.), annual medics (Medicago spp.) and clovers (Trifolium spp.). Six isolates of L. trifolii were cultured from leaves of M. sativa, M. polymorpha L. and M. truncatula Gaertner from Oklahoma and Texas, and the ribosomal internal transcribed spacer (ITS) region of each isolate was amplified and sequenced. No variation was observed among the ITS sequences of these isolates or with the ITS sequences of Australian isolates reported in Genbank. In an effort to better understand the host-pathogen interaction, L. trifolii was transformed using Agrobacterium tumefaciens AGL-1 carrying the binary vector, pOHT-sGFP. Single-ascospore cultures of transformants were resistant to hygromycin and expressed green fluorescent protein in hyphae, pseudothecia and ascospores. T-DNA integration into the genome of L. trifolii was confirmed by PCR. Infection of Medicago leaves by transformants will be cytologically examined using fluorescent microscopy.

return to top