Molecular screening for TSWV resistance in F2 pepper (Capsicum annuum L.) genotypes from different genetic background

A CAPS marker linked to resistance gene to TSWV in pepper was employed to classify tolerant and susceptible plants at co-dominant level (RR, Rr, rr). During this process selecting heterozygote and homozygote resistant plants from different genetic backgrounds may show some deviations. In this experiment for determination of heterozygote/homozygote resistance/susceptible genotypes developed from different genetic background using two enzymes (XbaI and TaqI) separately at the same time and assessing the gel pictures together was studied. For this purpose, the F2 pepper plants belonging to two different population and each population developed from different genetic background were tested with SCAC568 marker. The genomic DNA of 110 plants representing both populations were amplified with SCAC568 CAPS marker and the PCR products were digested with XbaI and TaqI enzymes. The digested fragments were separated in agarose gel and visualized under UV light. The genotypes belonging to one population gave the expected segregation (1RR: 2Rr: 1rr) at F2 level while the other population required digestion of PCR products with both XbaI and TaqI enzyme separately and assessment the results together to determine resistant and susceptible plants at co-dominant level and to obtain the expected F2 segregation. The results showed that SCAC568 CAPS marker can be used successfully to select the resistant and susceptible genotypes in F2 segregation population by employing two enzymes