Farkli zamanlarda ve konsantrasyonlarda gibberellin A4/7/9 karişimi uygulamasinin kizilçam (Pinus brutia Ten.) tohum bahçesinde çiçeklenme üzerine etkisi

The aim of this study is to determine optimum application time and optimum concentration of gibberellin A4/7/9 (GA4/7/9 ) for stimulation of flowering in Turkish red pine (Pinus brutia Ten.) seed orchard. The trees used in this study belong to six different clones (clone numbers 9283, 9289, 9290, 9292, 9294 and 9295) originated from Gündoğmuş-Eskibağ and they are located in a Turkish red pine seed orchard in Antalya-Çığlık district which was founded in 1992. Five types of treatments were applied on the trees: distilated water, 95 % ethyl alcohol, 10 mg/ml GA4/7/9, 20 mg/ml GA4/7/9 and 30 mg/ml GA4/7/9. Applications were realized on 15th July, 04th August, 25th August and 15th September in the years 2006 and 2007. Counting of female and male flowers was done between 29th March and 17th April in subsequent years (2007 and 2008) following applications. As a result of first year (2006) application, both female and male flower numbers increased. The most effective GA4/7/9 concentration on female and male flowering was 30 mg/ml and 20 mg/ml respectively. In the first year, optimum application time for female flowering was determined as 15th September 2006 and that for male flowering was 04th August 2006. In the second year (2007) application there were no significant difference between the control and three level of concentrations. However, each of the three GA4/7/9 concentrations on female flowering showed significant increases, and the highest increase was with 30 mg/ml GA4/7/9 concentration. The second year, optimum application time for both female and male flowering was determined as 25th August 2007. In both 2007 and 2008, flowering responses of different clones were different with regard to GA4/7/9 applications. Most of clones responded positively to different levels of GA4/7/9 applications. In general, the response of poorly flowering clones to GA4/7/9 applications were relatively higher than that of better flowering clones. Both female and male flower numbers in all of the trees included in this study decreased in the second year compared to the first year, at rates 36.56 % and 41.86 %, respectively. In other words, the first year was a rich flowering year and the second year was relatively poor flowering year. GA4/7/9 applications were more effective on increasing female flowering in rich flowering year. In the first year (2007), the highest diameter increase was observed on the control group and this increase was found to be statistically significant. The highest height increase was also obsereved on the control group, the lowest increase being on 30 mg/ml GA4/7/9 application group and difference between control and 30 mg/ml GA4/7/9 application group was found statistically significant. However, in 2008, the differences between the control group and application groups both in height and diameter increments were not found statistically significant.KEY WORDS: Pinus brutia Ten., seed orchard, Gibberellin A4/7/9, application time, stem injection, flowering, female flower, male flowerCOMMITTEE: Prof. Dr. Ş. Fatih TOPCUOĞLU (Supervisor)Prof. Dr. Kâni IŞIKProf. Dr. Kenan TURGUTProf. Dr. Mustafa GÖKÇEOĞLUDoç. Dr. Hüsnü ÇAKIRLAR