Full Length Research Paper

The effects of different warm stratification periods on the seed germination of some Rosa taxa

Ş. Alp¹*, F. Çelik² N. Türkoğlu³ and S. Karagöz⁴

¹Yuzuncu Yıl University, School Of Gevaş, 65080, Van, Turkey.

²Yuzuncu Yıl University, School of Ozalp Van 65080, Turkey.

³Yuzuncu Yıl University, Department of Horticulture Faculty of Agriculture, Van 65080, Turkey^.

⁴Yuzuncu Yıl University, Environmental Studies Research Center, 65080 Van, Turkey.

*Corresponding author. E-mail: alpsevket@hotmail.com. Tel: +90.432.6122434. Fax: +90.432.6122435.

Accepted 11 September, 2009

   Abstract

In this study, the effects of different warm stratification periods on the seed germination of some Rosa species such as Rosa heckellana ssp. vanheurckiana, Rosa canina, Rosa pulverelanta and Rosa dumalis naturally grown in the Van region were investigated. In 2007, seeds of these species were kept at 25°C warm stratification for 10, 11 and 12 weeks, and then transferred to 5°C for cold stratification till the initiation of germination. Germination response to treatments of R. heckellana ssp. vanheurckiana seeds was different compared to the other species. The seeds of R. heckellana ssp. vanheurckiana germinated in a short time (when they kept in warm stratification followed by cold stratification between 1 - 3 weeks). The seeds of the other species required 5 months of cold stratification after warm stratification to overcome seed dormancy. The overall germination percentage were 18.80% in R. canina, 13.80% in R. pulverelanta and 13.53% in R. dumalis at 25°C of warm stratification followed by 5°C cold stratification. We determined that for these three taxa, the most appropriate method of stratification was 11 week warm stratification followed by cold stratification.

Key words: Rosa ssp., germination, warm stratification, cold stratification, Van Lake.