Breeding tomato lines resistant to race T1 and T3 of Xanthomonas vesicatoria

In Bulgaria two races (T1 and T3) of Xanthomonas vesicatoria, causing bacterial spot on tomato grown in the field are spread. The aim of the present investigation was to develop resistant to that pathogen economically valuable tomato lines for field production. Lines obtained by hybridisation between wild Lycopersicon species (L. pimpinellifolium PI 126925, L. chilense LA 460, L. peruvianum var humifusum PI 127829 and L. hirsutum f. glabratum. PI 134418) used as sources of resistance and tomato cultivars or lines were studied. Over hundred tomato lines were examined, the lines 36, 44, 44/1, 163/1, 165/2, 167, 167/4, 267, 270 being selected as perspective for this country. They manifested high resistance predominantly to the most wide spread in Bulgaria race T3. The resistant plants from group I were obtained by hybridisation with L. pimpinellifolium PI 126925. High numbers of resistant lines were selected in group 2 with participation of L. chilense LA 460 and L. peruvianum var humifusum PI 127829. The group 3 lines originating from L. hirsutum f. glabration PI 134418 decrease the resistance to race T1 while their resistance to T3 did not change. The selected nine lines possess valuable morphological and agronomic characters and could be used to breed resistant tomato varieties and as source material in cross breeding programmes.