Determination of optimal irrigation on establishment and height growth of one-year Paulownia tomentosa seedlings

Paulownia species، which are fast-growing endemic species in China and Japan، have been used for establishing green space and park and inter-cropping with many kinds of crops in many countries. The aim of this study was to investigate the effect of irrigation on one-year Paulownia tomentosa seedlings in the climatic and edaphic condition of West Azarbayjan، Iran. Random factorial experimental design was applied with 3 irrigation levels (5، 10 and 15 liter) and 2 irrigation period treatments (3 and 6 days) with 10 replicates. Seedling’s height increment was measured at the end of each month during the growth season. The maximum height growth of Paulownia tomentosa in different treatments was observed in the first month and the seedling height was not considerably raised during the upcoming months. The seedlings of the treatment which were irrigated with 5 liters and with 6 days interval were dried and the seedlings of the treatment with 5 liters irrigation and with 3 days interval had the minimum mean of total height (8. 7cm) in comparing with other treatments (10. 9-11. 8cm). Furthermore، with increasing the irrigation amount and decreasing the irrigation interval، the seedling’s height growth was not altered significantly. Therefore we concluded that the best irrigation regime for suitable height growth of one-year Paulownia tomentosawas with 10 liters irrigation and with 6 days interval، for decreasing the cost and water consumption.