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ŠUMARSKI LIST 11-12/2014 str. 47     <-- 47 -->        PDF

Young 1992; RBG Kew 2014). The average 1000-seed weight was 169.7 g, while that of A. sachalinensis (F. Schmidt) Mast. var. gracilis (Kom.) Farjon, the lightest seeds, was 4.2 g. In another study (Keskin and Şahin 2000), the 1000-seed weight of A. cilicica was found to be 139.1 g and 226.0 g in poor and mast seed years, respectively. The 1000-seed weight of A. nordmanniana (Steven) Spach subsp equi-trojani (Asch. et Sinb.) Coode et Cullen and A.n. subsp. bornmuelleriana (Mattf.) Coode et Cullen, other Abies taxa in Turkey, were 63.2 g (Aslan 1982) and 82.9 g (Turna et al. 2010), respectively.
There was a great variation between and within the provenances in terms of the morphological traits of the seeds. The average length, width, thickness, and weight of a seed were 14.26 mm, 7.13 mm, 4.44 mm, and 0.170 g, respectively. Similar variations are generally due to different genetic characteristics, environment, and events during the period of seed development (Leishman et al. 2000; Desai 2004).
We found that, for seed from all five provenances, 6 w of pre-chilling fully eliminated dormancy and produced an overall average germination percentage of 79.6 %. The average GP in Abies seeds is less than that of many other conifer species due to empty and insect-infected seeds (Edwards 2008). Keskin and Şahin (2000) obtained about 50 % GP at 23 °C to 25 °C in A. cilicica seeds.
The real germination capacity of the dormant seeds is generally seen after the full elimination of dormancy (Copeland and McDonald 1999; Baskin and Baskin 2001; Smith et al. 2002). After pre-chilling for 6 w, which fully removed dormancy, the provenances divided into two groups in terms of GP and germination speed (Figure 3). The average GP of A. cilicica subsp. isaurica seeds (Anamur and Bucak) was significantly lower than that of A. cilicica subsp. cilicica (Kozan, Saimbeyli, Göksun). Further research over several consecutive years is needed to determine the true differences between the two subspecies.
In general, germination accelerates with increased temperature and increased duration of pre-chilling (Edwards 2008; Yilmaz 2008 and 2010). Similarly, we found that germination speeds increased with the duration of pre-chilling and an increase in the germination temperature (Table 6, 7; Figure 4).
This study clearly revealed that the seed of A. cilicica has non-deep physiological dormancy. The fresh (no pre-chilling) seeds from the provenances of Göksun and Saimbeyli demonstrated relatively high percentages of germination. On the other hand, the GPs of non-chilled seeds from the other three provenances (Kozan, Anamur, Bucak) were very low, due to physiological dormancy. The dormancy depth changes each year depending on the timing of collecting the cones (Fenner and Thompson 2005). Since these cones were all collected late in autumn before natural dispersal, the dormancy depth may be reduced because they were still on the trees. Studies over several consecutive years of A. cilicica seeds from the same provenance are likely to give more meaningful information about the depth of dormancy.
The duration of pre-chilling necessary to fully remove dormancy varied by the provenances. Although 2 w pre-chilling was sufficient for the seeds from Saimbeyli, the seeds from Kozan required 4 w pre-chilling to achieve full elimination of dormancy. Seeds from the other three provenances required 6 w of pre-chilling to attain full removal of dormancy. Based on the results of these five provenances, pre-chilling for 4 w to 6 w can be recommended for A. cilicica seeds; this is in agreement with the average pre-chilling requirement of Abies seeds, 4 w to 8 w (Gosling 1999;