The effect of different irrigation levels on growth parameters of ash (Fraxinus rotundifolia Mill) seedlings in green space of Tehran city

Document Type : Scientific article

Authors

1 Department of Forestry ,Faculty of Natural Resources, University of Guilan

2 Department of Forestry, Faculty of Natural Resources, University of Guilan, Somehsara, I.R. Iran

3 Assistant Prof., Department of Range and Watershed Management, University of Guilan, Somee Sara, Iran

4 Assistant Professor, Department of Irrigation and Drainage, Faculty of Aburaihan, University of Tehran, Tehran, Iran.

Abstract

Improvement of the irrigation water efficiency through irrigation management is one of the most effective ways to save water use in the agriculture. The experiment was conducted to evaluation of different irrigation levels on various indicators of growth in ash in 2016 and 2017. The experiment treatments were included irrigation (50, 75, 100 and 125% water requirements) as main factor and time as sub factor that was accomplished in a split plot replicated in time at randomized complete block design with four replications. Irrigation was done with estimated value of irrigation water requirements using FAO equation and WUCOILSIII method. The results showed that in both years irrigation with 50% of plant water requirements resulted in significant decrease in height, shoot length, crown diameter, leaf abundance, succulence and leaf area index in comparison with the control treatment. Results indicated that water demand varied from 50% to 100% basic water requirement due to the growing season (based on time and growth stage of the seedling) and air temperature. Generally, by examining the growth index and succulence of plants under irrigation and considering effective rainfall and irrigation efficiency, irrigation at 75% of basic water requirement in studied field was recommendable as optimal irrigation.

Keywords