Screening for resistance in wild Lycopersicon species to Fusarium oxysporum f sp lycopersici race 1 and race 2

Wild Lycopersicon accessions were screened for resistance to the Fusarium wilt disease caused by Fusarium oxysporum f.sp. lycopersici (Fol) race 1 and race 2. In total, four isolates of each race were used. Among 17 accessions of six Lycopersicon species tested, a wide genetic variation for wilt resistance was observed. Most accessions were highly susceptible, some showed intermediate resistance, but one accession of L. cheesmanii (G1.1615=PI 266375) and two accessions of L. chilense (G1.1556 and G1.1558) were highly resistant to Fol races 1 and 2. The resistance in the latter three accessions equalled or was higher than the resistance determined by the known I-genes, that have been widely used in breeding programmes. These newly found resistant accessions provide breeders with more opportunities for Fusarium disease resistance and may contribute to our understanding of Fusarium disease resistance gene organisation and evolution.