BEGOMOVIRUS RESISTANCE GENES IN TOMATO (Solanum lycopersicum L.) GERMPLASM COLLECTED IN PANAMA

Abstract

The aim of this study was to identify begomovirus resistance genes in 78 wild cultivars and 11 improved varieties of tomato, using molecular markers. The studied cultivars were collected as part of the project FTG-7086/07/2007. The amplification of the genes Ty-1, Ty-2 and Ty-3 was performed by PCR using specific primers JB-1, T0302 and P6-25, respectively. The JB-1 marker band ​ of 400 bp (ty-1/ty-1) was identified in 40 wild cultivars and six varieties and the T0302 marker band of 800 bp (ty-2/ty-2) was identified in 60 wild cultivars and 10 varieties. No cultivars carrying the dominant alleles Ty-1 and Ty-2 were found. Fifty-eight wild cultivars had only one P6-25 marker band 320 bp (ty-3/ty-3). Resistance gene Ty-3 was identified in wild cultivars 24, 65, 67, 70, 71; as well as in the varieties Anabella F₁ and IDIAP T9m, carrying the bands P6-25 630 and 320 bp (Ty-3a/ty-3). The variety Se 122 showed three bands of 320, 450 and 630 bp (Ty-3/Ty-3a). The analysis of the nucleotide sequences of the wild cultivars 65, 67, 70 and 71, as well as the varieties Anabella F₁ and IDIAP T9m confirmed the identity of the allele Ty-3a.