Research of cultivation opportunities for some Gentiana L. species

Gentiana L. genus's homeland is Asia, shows spread almost all over the world except North Africa, Eastern Australia and low altitude in natural tropical regions. Belonging to the Gentiana genus one of them is endemic in 14 taxa is located our country. With this thesis, by revealing the conditions of generative propagation, growing techniques and the ornamental characteristics which spread naturally in Turkey and have potential the ornamental plants of some Gentiana (G. boissieri Schott & Kotschy, G. cruciata L., G. gelida Bieb., G. septemfida Pallas, G. verna L. subsp. balcanica Pritchard) taxa aimed to determine the possibilities of taking culture. In the study, first determined the natural distribution locations of Gentiana taxa and later collected plant, seed and soil material from these locations. As a result of analyzes all taxa are grown in clay or clay loam soils. In terms of pH, except G. septemfida taxa the other taxa well grown in neutral soils, the G. septemfida taxa grown in acidic soils furthermore all taxa show improvement in good or high range of containing organic matter in soil. In "determination of techniques for propagation from seed" trial, the effect of light, temperature and different pre-treatment methods on germination characteristics and the effect of different sowing times on emergence characteristics of seeds belonging to the taxa were determined. Results of the study, while acquiring germination rates between 0.00 to 13.50% from the control seeds, soaking in 750-4000 ppm GA3, and light (16 µmol·s-1·m-2) treatments increased this rate to % 83,00 - 98.00 range. The highest emergence rate was obtained from "sown in October" pre-treated seeds between 56.00 - 97.50%. The scope of studies in growing techniques, seed propagated crops cultured for two vegetation periods in different growing areas and medium and development conditions were observed. As a result, generally all taxa showed good improvement in; 35% of shadow area, loam or clay loam, neutral, unsalted or medium salted, low lime and high organic matter in the medium. In this study, identified the cultivation possibilities of Gentiana taxa by determining the propagation from seed characteristics, growing techniques, adaptation ability, ornamental plant characteristics and provided recommendations on cultivation of the taxa under grower conditions.