Morpho-Physiological Responses of Black Locust (Robinia pseudoacacia L.) Seedlings to Drought Stress

This study was conducted to study of morpho-physiological responses of Robinia pseudoacacia L. seedlings under drought stress by irrigation period at 4 levels (intervals of 4, 8, 12 and 16 days). The experiment was performed as completely randomized design in a greenhouse environment. Results indicated that all studied traits were affected by water stress, except water use efficiency (WUE). The greatest value of most traits was observed in 4-day irrigation. Seedlings treated by 12- day irrigation had the largest root length. The biggest root dry weight belonged to seedlings irrigated in intervals of 4 and 8 days. Irrigation periods of 8 and 16 days remained the highest water use efficiently (WUE) and electronic leakage (EL) for seedlings, respectively. Generally, seedlings with 4-day irrigation period indicated the best response to drought stress. Of course, 8-day irrigation period showed a relatively well response to water stress especially in terms of survival and growth parameters whereas it can be considered as an appropriate and economic irrigation. Similar investigations can be performed in forest nurseries where climate is adapted for R. pseudoacacia growing.