Response of growth indices of Judas tree seedling to different irrigation periods

Judas tree (Cercis siliquastrum L.) is a suitable species for improving the soil nitrogen fixation and creating the natural landscape in parks and roadsides. This study was aimed to investigate the growth, development and drought resistance of Cercis seedlings by applying different irrigation periods. First, the seeds of Cercis were treated to germinate and reach to seedling phase (30 cm in height) for 90 days. Then, the seedlings were examined in a completely randomized design with four irrigation periods (4, 8, 12, and 16 days) and three replicates for 70 days. Irrigation significantly affected all morphological characters whereas stem length, root length, specific leaf area, shoot dry mass, leaf dry mass (p≤ 5%) and other characters (p≤ 1%) were different among the irrigation periods. The highest stem length, collar diameter, leaf number, leaf area, shoot dry mass, leaf dry mass, collar diameter growth, height growth and survival rate were observed in 4-day irrigation period. Seedlings with 8-day irrigation period had the greatest root volume, root dry mass and plant dry mass. This is while that, the 8-day irrigation period induced the greatest root length, specific leaf area and root/shoot ratio. The results revealed that the 4-day irrigation period was suitable for raising the Cercis seedlings; however, due to the satisfactory survival and growth, as well as the low cost and easy maintenance of seedlings, the 8-day irrigation period can be a good alternative for seedling production of this species.