Serap KIRMIZI, Gürcan GÜLERYÜZ, Hülya ARSLAN, F. Selcen SAKAR

Nadir ve endemik Pedicularis olympica (Scrophulariaceae) türünde nemli soğuklama, gibberellik asit ve skarifikasyonun tohum dormansisi üzerindeki etkileri

Bu çalışmada Uludağ’da nemli alanlarda yayılış gösteren nadir endemik Pedicularis olympica Boiss. (Scrophulariaceae) türünün çimlenme gereksinimleri araştırılmıştır. Çalışmada, skarifikasyon, 15 gün nemli soğuklama (+4 °C) ve farklı dozlarda gibberellik asit (GA3; 100, 150 ve 250 ppm) ile hormon ve nemli üşütme kombinasyonlarının karanlık (20 °C) ve fotoperiyot (sırasıyla 20/10 °C; 12/12 s) şartlarında etkileri araştırılmıştır. GA3 uygulamalarının dormansiyi kırmada etkili olduğu saptanmıştır. En yüksek çimlenme oranı 250 ppm GA3 ile muamele edilmiş tohumlarda bulunmuştur; karanlık şartlarda nemli üşütmede % 64 iken fotoperiyotta % 75 çimlenme gerçekleşmiştir. Ayrıca, 250 ppm GA3 ile muamele edilen tohumlarda ortalama çimlenme süresi de anlamlı derecede kısalmıştır. Final çimlenme oranları ve ortalama çimlenme süreleri arasında anlamlı fark grupları sadece fotoperiyot şartları altında bulunmuştur.Skarifikasyon çimlenmeyi uyarmıştır ve en yüksek çimlenme 15 dakika skarifikasyon sonucunda bulunmuştur (% 78). 90 güne kadar yapılan nemli üşütme muamelelerinde dormansi kırılmamıştır. P. olympica türünün çimlenme gereksinimlerinin bulunduğu habitatla uyum içinde olduğu bulunmuştur. Bu da türün yerleşme ve devamlılığında bir ekolojik avantaj olarak değerlendirilebilir.

Anahtar Kelimeler:

Tohum dormansisi, Pedicularis olympica, endemik, soğuklama, gibberellik asit, skarifikasyon

Effects of moist chilling, gibberellic acid, and scarification on seed dormancy in the rare endemic Pedicularis olympica (Scrophulariaceae)

We investigated the germination requirements of a rare endemic plant species, Pedicularis olympica Boiss. (Scrophulariaceae), which grows in wet habitats on Uludağ Mountain, Turkey. We studied the effects of scarification, moist chilling (+4 °C) for 15 days, different doses of gibberellic acid (GA3; 100, 150, and 250 ppm) and combined hormone and moist chilling treatments under dark (20 °C) and photoperiod (20/10 °C; 12/12 h, respectively) conditions. GA3 was able to break dormancy. The highest germination rate was found in the seeds treated with 250 ppm GA3; 64% of these seeds germinated when treated with moist chilling and incubated in the dark, while 75% germinated under photoperiod conditions. Moreover, mean germination times were significantly lower in the seeds treated with 250 ppm GA3. Significant differences in final germination percentages and mean germination times were found only for treatments under photoperiod conditions. Scarification also permitted germination; the highest germination rate (78%) was found with 15 min of scarification. Dormancy was not broken by moist chilling for up to 90 days. The germination requirements of dormant P. olympica seeds are found to be consistent with characteristics of its habitat. This can be considered an ecological advantage for the species' establishment and persistence.

Keywords:

Key words: Seed dormancy, Pedicularis olympica, endemic, stratification, gibberellic acid, scarification,

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