The effect of pyramiding resistance control genes on viral disease of tomato yellow ‎leaf curl virus (TYLCV) on photosynthetic pigments and some physiological traits in ‎different lines

Tomato yellow leaf viral disease (TYLCV) is one of the most damaging agents that causes very high yield losses worldwide and has spread to most parts of Iran. Numerous strategies have been developed to combat this disease, but these methods have been practically ineffective. In order to investigate the role of transmission and combination of TY-2 and TY-1/3 gene loci in a number of sensitive and desirable line, the present study was performed.Results showed that the lines containing the two TY-2 and TY-1/3 gene loci experienced less damage regarding chlorophyll content and total protein content. In the study of proline content and PAL gene expression, it was observed that lines containing two gene loci showed lower levels of proline and gene expression. Also, in order to detect viral infection by polymerase chain reaction (PCR) using specific primers, it indicated that the virus genome does not replicate in the lines containing both gene loci. In general, the results of this study indicate the high role of the presence and pyramiding of two gene sites TY-2 and TY-1/3 in order to create resistance in tomato against TYLCV and lead to a reduction in damage against this virus.