Erfan Jamshidi - Department of Biology, Urmia Branch, Islamic Azad University, Urmia, Iran.
Maryam Parvini Kohneh shahri - Department of Biology, Urmia branch, Islamic Azad University, Urmia, Iran
Reza Darvishzadeh - Department of Plant Production and Genetics, Faculty of Agriculture and Natural Resources, Urmia University, Urmia, Iran.

Sclerotinia stem rot disease caused by Sclerotinia sclerotiorum is one of the most important diseases of sunflower. Telomeres are nucleoprotein structures at the ends of chromosomes that are essential for maintaining the integrity of the genome. The aim of this study was to determine the alteration of telomerase enzyme gene (tert) expression under fungal infection stress. The expression of tert gene in both susceptible (SDR۱۹) and resistant (LC۱۰۶۴-C) genotypes of sunflower was evaluated by qRT-PCR after infection with A۳۷ isolate of S. sclerotiorum. The results showed significant and drastic decreased levels of tert expression in both susceptible and resistant genotypes of sunflower, immediately after fungal infection. This depletion followed by mild variation when infection continued for more hours, which was more constant in resistant line, compared with the susceptible one. In conclusion, the expression of tertgene in sunflower is downregulated in response to Sclerotinia rot disease.

Fungal infection, Plants, Telomerase gene expression, qRT-PCR