Seed treatments to overcome dormancy of Tilia amurensis.

The present research was conducted to study the dormancy breaking treatments in Tilia amurensis seed. An experiment was conducted with four replications and three treatments，including three different concentrated sulfuric acid treatments (10, 30 and 60 min), varying concentrations of GA3(0, 100 and 300 mg/L) and 4 levels of stratification (0; 0-5 ℃, 30 d; 15-20 ℃, 30 d and 15-20 ℃, 10 d→0-5 ℃, 20 d). The germination percentage and mean germination time of treated seeds were significantly enhanced by mentioned treatments compared with control. It was concluded that altering temperature stratification was more effective on studied dormancy breaking traits than others. Moreover, cold stratification was a better treatment on breaking seed dormancy of T. amurensis seeds than concentrated H2SO4and GA3 treatments. Applying concentrated sulfuric acid for 30 min and 100 mg/L concentration of GA3 and stratification(15-20 ℃, 10 d→05 ℃, 20 d) results in higher germination in T. amurensis dormant seeds, and germination percentage reaches 90%.