Agricultural Microbes Genome 2 Conference

Poster: Genetic, Mutational, and Biochemical Technology
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CHROMOSOME LANDING ACROSS AVIRULENCE LOCI IN THE POTATO LATE BLIGHT PATHOGEN, PHYTOPHTHORA INFESTANS

¹ Scottish Crop Research Institute, Invergowrie, Dundee, DD2 5DA, United Kingdom

² University of Wageningen, Binnenhaven 9, Wageningen, 6709 PD, The Netherlands

Phytophthora infestans, which causes late blight of potato and tomato, is a globally important plant pathogen. On potato, resistance to late blight is conditioned by a gene-for-gene interaction between potato resistance (R) genes and P. infestans avirulence (Avr) genes. Six P. infestans Avr genes have been genetically mapped and AFLP markers have been identified tightly linked to these Avr loci. We have adopted a map-based cloning approach for cloning the Avr genes from P. infestans. A 10-fold genome coverage bacterial artificial chromosome (BAC) library was constructed and clones were pooled for screening by AFLP. Overlapping BAC clones which span two avirulence loci (Avr11, Avr4) have been identified, and BAC clones near two other Avr genes (Avr1, Avr2) have also been identified. Current and future efforts will be focussed on confirming the presence of Avr genes in the BAC clones, and identifying the functional Avr genes. Cloning of an Avr gene from P. infestans will yield insights into the molecular interaction between P. infestans and potato, and may form a basis for novel sources of resistance to late blight.