Investigation of rooting and growth characteristics of poplar clones in hydroponic and soil cultures

In this study, rooting and growth characteristics of different poplar clones from six species including Populus deltoides Bartram ex Marshall clone Lux, Populus nigra subsp. betulifolia (Pursh) W. Wettstein clone 17/13, Populus euramericana (Dode) Guinier clone 561/41, P. deltoides clone Samsun, Populus alba Linnaeus clone 49/9, Populus caspica (Bornmüller) Bornmüller, and Populus euphratica Olivier in hydroponic and soil cultures have been evaluated. In hydroponic culture, poplar cuttings were grown in plastic tanks and in soil culture, poplar cuttings were planted into plastic pots with 12 replications for each clone. The pot experiment was a Complete Randomized Design. Root length, stem diameter, stem height, and root and shoot dry matter of poplar plants were studied in hydroponic culture after 84 days and in soil culture three times at 6, 12, 18 weeks in 2017. In hydroponic culture, the cuttings of P. deltoides Lux and P. nigra betulifolia 17/13, and of P. deltoides Samsun and P. euphratica were among the first and last clones that rooted, respectively. Also, the lowest rate of rooting was observed in P. deltoides Samsun and P. euphratica clones. The highest values of all parameters except root length were obtained in P. euphratica. The highest root length and stem diameter were observed in clones of P. deltoides Lux, P. nigra betulifolia 17/13, P. euramericana 561/41, and P. deltoides Samsun. In soil culture, P. deltoides Lux, P. nigra betulifolia 17/13, and P. alba 49/9 showed the highest percentage of rooting compared to the other clones at the first measurement. All the clones except the clone of P. euphratica reached above 40 cm root length in each of the three measurement periods. The highest stem diameter, stem height, and shoot dry matter were obtained in clone of P. deltoides Lux and root dry matter in clone of P. alba 49/9.