An orchard without fungicides: a promise or utopia of biotechnology?

Abstract: Apple production in temperate climate with wet springs is hampered by diseases such as scab and fire blight. Producers need to apply frequently fungicides to control scab and may suffer severe losses through fire blight or apply antibiotics. Chemical treatments are currently questioned by retail sellers and consumers pushing for “zero residues”. Classical breeding has produced a large range of scab resistant cultivars; however none is currently substituting the highly susceptible but popular cultivars. Ten years ago the first scab resistance gene originated from the wild Malus floribunda 821was cloned and demonstrated to incite full scab resistance inserted into a Gala apple under the control of a 35S promoter. Since technology developed so that cisgenic scab resistant Gala trees were developed and are currently tested in field trials. Also fire blight resistance candidate genes are described and functionality tested. This paper gives a short overview on the current situation.