Effect of temperature on germination and mobilization of protein reserves of three bread wheat cultivars

In order to investigate the effect of temperature on the mobilization of protein reserves of wheat cultivars and seedling traits a factorial experiment conducted based on a completely randomized design at seed technology laboratory of  the Faculty of Agricultural sciences, University of Mohaghegh Ardabili with three replications. Treatments were three germination temperatures including 10, 20 and 30 ◦C and three wheat cultivars (Sardari, Finikan and MV17). Studied traits included germination percentage and rate, seedling dry weight, protease activity and protein content, respiration index and distribution of dry matter to seedling parts. Results showed that the highest germination percentage, rate and mean of germination time were related to 20 ◦C in all cultivars. The highest protein contentin in seed residual (8.7%) was observed in Sardari cultivar at 10 ◦C,but the lowest activity of protease (4.63 unit mg-1) was related to Finikan at this temperature. The highest amount of seed material lost as respiration (20.21) attained in MV17 cultivar at 30◦C. The highest seed reserves mobilization efficiency was related to Finikan and MV17 (1.23 and 1.2 respectively) at 20◦C. Seed dry matter distribution to radicle and plumule was different in cultivars and temperatures and the highest distribution to radicle (6.27%) and plumule (15.84%) were related to MV17 and Finikan cultivars, respectively at 20 ◦C. Seed protein reserves remobilization efficiency was the same in all cultivars at 20 ◦C, but MV17 at 10 ◦C and Finikan at 30 ◦C had the highest efficiency. In conclusion, higher germination percentage of MV17 at 20 ◦C can be related to the higher activity of protease