Abstract

This study describes the changes in catalase and peroxidase activities in dryness tension condition on two levels (tension and without tension) and its effect on the rate of cell membrane stability and chlorophyll content in probable lines (Sardari and Azar2), half-probable (DH-2049-3 and HN7/OROFEN//BGN8/3/SERI/4/ (and sensitive (SARA-BW-F6-06-85-86-29-1 and TEVEE'S'//CROW/VEE'S) of wheat in factorial form in randomized complete blocks of basic plan in triplicates. The dryness tension caused increase in peroxidase enzyme activity of Azar2, Sardari and DH-2049-3. Although no increase in peroxidase enzyme activity was shown, Sardari still had the highest rate of enzyme activity in drought condition. In lines of (Sardari) even though in dryness condition, there was no increase in peroxidase enzyme activity, but this line had the highest rate of enzyme activity in dryness condition. As regard the activity of catalase enzyme in tension condition in all investigated lines, we perceived stability or decrease, but we did not perceive any relation between the activity of the enzyme and dryness resistant. The highest index of chlorophyll resistance in the tension condition was perceived in lines of (Azar2, Sardari,HN7/OROFEN//BGN8/3/SERI/4/…). Also the most stabilized and the most inconstant cell membrane in tension condition were related to lines of sardari, DH-2049-3) and TEVEE'S'//CROW/VEE'S. In dryness condition between peroxidase enzyme activity with the function and stability of chlorophyll b, we perceived positive correlation, whereas we did not perceive positive correlation between catalase enzyme activities with the function. Also in regard to the existence of a negative correlation between peroxidase enzyme activities with cell membrane stability, it can be concluded that peroxidase enzyme are more active in dryness tension condition, which leads to increase in cell membrane and chlorophyll stability and it is related to the dryness with resistance of different lines.

Key words: Wheat lines, catalase, peroxidase, cell membrane stability, chloropyll resistance index.