FIRST EVIDENCE FOR DIFFERENCES IN FIRE BLIGHT RESISTANCE AMONG TRANSGENIC PEAR CLONES EXPRESSING ATTACIN E GENE

Agrobacterium-mediated transformation of the fire blight susceptible pear cultivar Passe Crassane, with a gene from Hyalophora cecropia coding for a small lytic peptide active against several Gram-negative bacteria (Attacin E) was attempted, using a previously described protocol.
Eleven transgenic clones were obtained after transformation with EHA101 pFM3002 containing the Attacin E gene driven by the CaMV35S promoter.
Integration and expression of the transgene were confirmed by PCR and RT-PCR, respectively. In vitro tests for fire blight resistance were performed by leaf inoculation with a virulent strain of E. amylovora (5 x 10⁷ cfu/ml). The tests distinguished clones with enhanced resistance, ten days after inoculation of the in vitro shoots.
Different levels of synthesis of attacin were detected by western blot analysis.
Results from in vitro inoculations and western analysis were in general agreement.
Semi-quantitative RT-PCR also indicated higher transcription levels in some resistant clones.

VIII International Workshop on Fire Blight

J.P. Reynoird, F. Mourgues, E. Chevreau, M.N. Brisset

Attacin, Erwinia amylovora, pear

https://doi.org/10.17660/ActaHortic.1999.489.39