The effects of different container media on Turkish alder (Alnus orientalis Decne) seedling characteristics

Turkish alder (Alnus orientalis Decne.), which belongs to the genus Alnus of the Betulaceae family, is among the species growing naturally in Türkiye. Turkish alder is an endemic tree species for the Eastern Mediterranean that can be used in many areas such as industrial plantations, restoration of waterfronts, rehabilitation of mining and landfill sites and urban afforestation. The aim of this study was to investigate the effect of different container media on seedling characters of Turkish alder. The seeds were collected from Bucak, Anamur and Fethiye where Turkish alder is naturally distributed. Two different media were used in the experiment. For the first medium (soil), 50% forest soil + 30% peat + 20% fertilizer was used. For the second medium (perlite), 50% perlite + 50% river sand was used. Diameter and height values of all seedlings of Bucak, Fethiye and Anamur Turkish alder populations were measured in August, September, October, November and December in soil and perlite environments. In December, a total of 90 randomly selected seedlings from three populations grown in soil and perlite media were divided into branches, trunk and root parts and biomass measurements were made. While no statistical differences were observed in Turkish alder populations in soil media, significant differences were observed in terms of diameter values. On the other hand, no statistical differences were found in terms of height and diameter in perlite media. In December, final heights in perlite varied between 12.79 cm and 18.07 cm, while in soil media they varied between 37.63 cm and 41.80 cm. Final diameters ranged between 4.30 mm and 5.32 mm in perlite media and between 9.83 mm and 11.33 mm in soil media. It was observed that the maximum increase in height of the seedlings of alder populations in perlite media was between 44% and 50% in October. In seedlings of all populations, the lowest diameter and height increases were observed in December in both growing media. The ratios of growing media in the variance of height and diameter values in seedlings of alder populations were found to be 45% and 29%, respectively. It was observed that the highest variance in height values was caused by the environment (45%) and the highest variance in diameter values was caused by the month (%37). Statistically significant differences were found in the T-test analyses of lateral branch, stem, root, total biomass, above-ground biomass of alder seedlings belonging to all populations in soil and perlite environments. While the below-ground biomass of the seedlings of alder populations grown in perlite medium was approximately 4 times the above-ground biomass, the below-ground biomass of alder seedlings grown in soil medium was approximately 2 times the above-ground biomass. Bucak population had the lowest biomass in both media. The biomass of the seedlings belonging to the Fethiye population was the highest in the soil media, while the Anamur population took the first place in the pertlite media.