tHe effect of Different irrigation levels on groWtH of fruitless MulBerry ( MORUS ALBA . fruitless ) in green space of teHran

This study was conducted to assess the effect of different irrigation levels on some growth characteristics of fruitless mulberry (Morus alba. Fruitless) in the condition of Tehran landscape during two consecutive years, 2016 and 2017. Therefore fruitless mulberry water requirements were computed using FAO penman-monteith method and WUCOLS III model. A field experiment was performed as split plot based on randomized complete block design with four replications. The effect of four irrigation levels and 125% water requirement on some parameters of fruitless mulberry seedling were evaluated in seven months. Results showed that the lowest amount of water requirement was in April in both years, whereas it reached its peak in Jun and July 2016 and 2017, respectively. Irrigation at level of 50% water requirement significantly led to a decrease in current monthly increment of seedling height, shoot length, stem diameter, crown diameter and leaf vitality, and also an increase in proline content, shoot dry matter and leaf dry mater in comparison with the control treatment. There was not any significant difference in the most parameters measured between 75 and 100% water requirement treatments. Generally speaking, the results obtained showed that mulberry trees can be irrigated at the level of 75% water requirement from April to August and 100% water requirement in October in the landscape of Tehran.