TRANSGENIC ‘ROYAL GALA’ APPLE EXPRESSING ATTACIN E HAS INCREASED FIELD RESISTANCE TO ERWINIA AMYLOVORA (FIRE BLIGHT)

Genes encoding the lytic proteins attacin E, hen egg white lysozyme, and the cecropin analogs, SB-37 and Shiva-1 have been transferred to ‘Royal Gala’ apple by Agrobacterium-mediated transformation. In 1998, 2- and 3-yr-old field grown plants of 64 lytic protein-transgenic lines were artificially inoculated with E. amylovora and % of the current season’s shoot length blighted (SLB) was determined. 28 transgenic lines developed significantly less fire blight than non-transgenic ‘Royal Gala’ controls. One transgenic line, TG138, containing the attacin E gene under the control of the proteinase inhibitor II promoter, had only 5% SLB compared with 56% SLB in non-transgenic ‘Royal Gala’ controls, and 37% SLB in the moderately resistant ‘Liberty’ controls.
Western analysis indicated that TG138 had a high constitutive level of attacin expression. Northern analysis of in vitro material confirmed the constitutive expression of attacin in TG138, but indicated elevated attacin expression 1 hr following leaf wounding. The first flowers on lytic protein-transgenic ‘Royal Gala’ plants were observed in the field in 1998. Fruit of several lytic protein-transgenic Royal Gala lines will be analyzed for lytic protein-gene expression and fruit quality in 1999.

Eucarpia symposium on Fruit Breeding and Genetics

J.L. Norelli, E. Boresza-Wysocka, J.P. Reynoird, H.S. Aldwinckle

lytic proteins, antimicrobial proteins, hen egg white lysozyme, cecropin, SB-37, Shiva-1, genetic engineering.

https://doi.org/10.17660/ActaHortic.2000.538.111