The future of disease-resistant apples

Integrated and biological cultivation methods are becoming increasingly important. The situation concerning the authorization of pesticides is becoming more critical as increased attention is focused on the conservation of the environment. An alternative solution is the cultivation of resistant cultivars which can be grown with much less pesticides. It is still the aim of the Pillnitz apple breeding to combine improvements in fruit quality + yield + resistance to different pathogens in new cultivars. Early-, mid-, late-season apple cultivars were selected in two series, Pi- and Re-cultivars((R)). The Re-cultivars((R)) guarantee a high degree of resistance. Triple and multiple resistant cultivars are selected with resistance to scab, mildew and fire blight: 'Remo', 'Regia' 'Rewena', and 'Rebella'. 'Rebella' was found to have resistance also to bacterial canker, red spider mite and abiotic damages. Various degrees of scab infection on V-f-resistant cultivars has been observed since 1984 in Middle-Europe. No infection were found in cultivars with other genes such as 'Reglindis' (VA), 'Reka' (Vr), 'Regia' (Vr). New sources for resistance breeding especially for pyramiding of resistance genes were found in the Fruit Gene Bank in some Malus species and old apple cultivars. However, if the V-f-gene is overcome new resistance sources and cultivars with two or more different sources of resistance to stabilize healthiness in the field will be required in the future.