Gene expression in resistant and susceptible apple cultivars as a response to feeding of rosy apple aphids, Dysaphis plantaginea (Passerini)

• Applicant: Professor Dr. Claus P.W. Zebitz
• Subject Area: Plant Breeding and Plant Pathology
• Term: from 2003 to 2007
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 5418518

Non-chemical strategies in crop protection include indirect strategies like use of pestresistant plant varieties. For aphids, the knowledge of molecular mechanismus involved in plant-aphid interactions is an important prerequisite for the selection of genotypes expressing any resistance. However, aphid resistance genes have only be identified and characterized in a few plant species so far. The aim of this work is to elucidate the molecular and biochemical mechanismus involved in resistance of apple trees Malus domestica against its primary aphid pest, the rosy apple aphid Dysaphis plantaginea (Passerini). Gene expression in both resistant and susceptible apple cultivars after infestation with rosy apple aphids will be investigated by employing the cDNA-AFLP method (cDNA-Amplified Fragment Length Polymorphism). Fragments differentially expressed in both cultivars will be cloned and sequenced and their pattern of gene expression will be further verified by Northern blot analysis. Sequence comparisons of differentially expressed fragments to data bank entries might reveal homologies to already known genes, and will therefore indicate putative mechanisms of resistance of apple plants against aphids. The identification of such genes involved in resistance or susceptibility to rosy apple aphids will provide us with a better understanding of plant defence reactions and will allow the design of improved strategies for breeding aphid resistant applle cultivars.

• DFG Programme: Research Grants
• Participating Person: Professorin Dr. Annette Reineke