Molecular marker assisted transfer of resistance to TSWV in tomato elite lines

摘要

A backcross breeding programme was performed to transfer the Sw-5 gene conferring resistance to Tomato Spotted Wilt Virus (TSWV) to a fresh market (Poly 39) and a processing (AD-17) line of tomato, previously selected for good agronomic traits. In both cases, F_1BC_5, F_2BC_5, F_3BC_5 were obtained from F_1 crosses with the donor parent Stevens, an Sw-5 resistant variety. The backcross schemes were assisted by a CAPS (cleaved amplified polymorphic sequence) marker tightly linked to the resistant gene; the codominant nature of this marker was particularly useful to select resistant heterozygous/homozygous plants. Further, an inoculation test with a TSWV virus strain was also performed to confirm the successful introgression of resistance in both elite lines. The advantages of using MAS for disease resistance are also discussed.