Understanding the molecular basis for tomato resistance to the Fusarium wilt fungus Fusarium oxysporum f. sp. lycopersici
A. CATANZARITI (1), Y. Gonzalez-Cendales (1), H. Do (1), P. Bru (1), D. Jones (1) (1) Research School of Biology, Australian National University, Australia

The soil-borne vascular-wilt fungus Fusarium oxysporum f. sp. lycopersici (Fol) is a devastating pathogen of tomato capable of causing huge yield losses in susceptible cultivars. However, Fusarium wilt of tomato has hitherto been managed by the development of resistant cultivars carrying disease resistance genes introgressed from wild relatives of tomato; firstly the I (Immunity) and I-2 genes from Solanum pimpinellifolium and subsequently the I-3 and I-7 genes from S. pennellii. The I-2 gene encodes an intracellular coiled-coil – nucleotide-binding – leucine-rich-repeat (CC-NB-LRR) resistance protein, consistent with delivery of the corresponding Avr2 pathogen effector to the cytosol of the host plant. We have now isolated the I, I-3 and I-7 genes and found that I and I-7 encode cell-surface leucine-rich repeat receptor-like proteins (LRR-RLPs) and I-3 encodes a cell surface S-receptor-like kinase (SRLK), consistent with recognition of the corresponding pathogen effectors Avr1, Avr7 (yet to be identified) and Avr3 in the apoplast. We will report on the identification of these resistance genes and the results of our work directed towards understanding the signalling process and defence responses activated by the LRR-RLPs I and I-7.

Abstract Number: P17-504
Session Type: Poster