Response of Populus caspica Bornm. seedlings to flooding

In this study, hardwood cuttings of Populus caspica Bornm. were collected from three origins of Golestan (sub-humid), Mazandaran (humid) and Guilan (very humid) regions and their transplants were planted in nursery of Koloudeh, Amol, north of Iran. In July 2009, seedlings were subjected to flooding stress for 150 days. Experiment was carried out as Completely Randomized Block Design in four replications. Results showed that among control seedlings, survival rate of origins varied between 93.7 and 100%. Golestan origin showed maximum height and collar diameter increment and Guilan origin indicated highest root biomass, total biomass and leaf area. In flooded conditions, survival did not differ among the origins and it always was higher than 93.7%. Likewise, no significant differences of height and collar diameter increment, root biomass, and total biomass were found among the origins. Generally, although the values in most of attributes of seedlings were smaller under flooding than control, but seedlings of three origins displayed relatively good response to flooding. This study confirms that Populus caspica is a good flood-tolerant species and thus, it can be used for planting in wetlands, riversides and flooded areas of northern Iran