Searching for new resistance sources to tomato yellow leaf curl virus within a highly variable wild Lycopersicon genetic pool

The high variability found among Tomato yellow leaf curl virus (TYLCV) isol ates from different geographical areas makes progress in breeding for TYLCV resistance slow. By using Agrobacterium-mediated inoculation, we have identified several new resistant sources to TYLCV within a extraordinarily variable wild Lycopers icon gene pool, collected in semidesert areas of Ecuador and Peru changed i nto wet by "El Nino". This screening assay revealed a high susceptibility w ithin L. esculentum and L. pennellii. but different levels of resistance wi thin L. pimpinellifolium, and L. hirsutum. Resistance level was related to the collection place, being concentrated in accessions collected in Norther n Peru (Piura province). Agroinoculation allowed the selection of 4 Lycopersicon pimpinellifolium an d 2 Lycopersicon hirsutum accessions with higher level of resistance than a ccessions of these species previously reported, avoiding interference due t o vector resistance mechanisms reported in both species. These new resistance sources will be included in pyramiding strategies aime d at obtaining durable resistance to TYLCV.