Catalase and Metallothionein genes expression analysis in wheat cultivars under drought stress condition

Drought stress is one of the serious problems that restricted agronomic plant production worldwide. In molecular level, the harmful effect of drought stress is mostly caused by producing of large amount of reactive oxygen species (ROS). Catalase and Metallothionein genes have a crucial role to mope the hydrogen peroxide (H2O2) resulting reducing oxidative damage. In this research the gene expression pattern of Catalase and Metallothionein was studied in response to drought stress treatments. The treatments included - 0.3 bar, - 0.9 bar, - 8 bar and -12 bar and wheat varieties included Zagros (drought tolerant), Moghan (semi- tolerant) and Tajan (drought sensitive). The amount of cellular oxidative levels (TBARM) increased steady by intensify of drought stress levels. Real time PCR analysis showed different expression pattern for catalase and metallothionein encoded genes. Catalase gene expression was increased during drought stress up to -8 bar and reduced in -12 bar treatment, in all cultivars specially in Tajan cultivar. Metallothionein gene expression was linearly reduced during different levels of drought treatments especially in Zagros and Tajan cultivars. The most activity for both genes has observed in Zagros cultivar at -0.9 bar treatment. Whereas, Moghan cultivar showed most transcription for both genes at -8 bar treatment. Overall gene activities, content of chlorophyll (a, b) and whole plants appearance declined by high level of drought stress e.g. -12 bar treatment in all cultivars particularly in Tajan variety. Whereas, the moderate levels of drought stress treatments induced genes activitiy.