Germination of cretan date palm (Phoenix theophrasti-Phoenix theophrasti Subsp. Golkoy) and determining their seedling growth characteristics in different growing substrates

This study was carried out to determine germination characteristics, and investigate effects of growing substrates on seedling growth of Phoenix theophrasti (Karaöz/Kumluca) and Phoenix theophrasti subsp. golkoy (Göltürkbükü/Bodrum) taxa native to Turkey. The study was conducted into two main stages. In the first stage, some seed morphological traits were measured and germination of taxa were tested in petri dishes. Also, effects of sowing time (February and April) and taxon on emergence characteristics of seedlings were determined with sowing seeds on trays in sand + peat (2:1 by volume) mixture. In the second stage of the study, effects of taxon and growing substrate on seedling growth characteristics of Phoenix theophrasti (Karaöz/Kumluca) and Phoenix theophrasti subsp. golkoy (Göltürkbükü/Bodrum) taxa were investigated under a restricted fertigation program. In this experiment, seeds were directly sown in growing substrates filled in 3 L pots, and loamy soil+ well fermented manure+ sand (2:1:1 by volume), perlite+ peat (2:1 by volume), peat+ sand (2:1 by volume) mixtures were used as growing substrates. Germination tests indicated that germination percentages were 95,0 % and 96,0%, and there was no significant difference between taxa. In trays (emergence) experiment, there were significant differences in emergence characteristics related to sowing time, taxa and sowing time x taxon interactions, and the highest emergence percentage (83,4%) was recorded in Phoenix theophrasti subsp. golkoy (Göltürkbükü/Bodrum) seeds sown in April. Results related to growing substrates showed that there were significant differences originated substrates, taxa and substrate x taxon interactions in seedling growth characteristics such as leaf number, length and wide, and leaf mineral nutrient contents. The highest growth characteristics values were recorded for Phoenix theophrasti (Karaöz/Kumluca) seedlings grown on loamy soil+ well fermented manure+ sand (2:1:1 by volume) mixture.