Micropropagation and in vitro germination of endemic and critically endangered Thermopsis turcica (Fabaceae)

In this study, ecological status, in vitro seed germination and micropropagation of an endemicand endangered plant species, Thermopsis turcica, were investigated. It was determined thatclearing new agricultural lands and holding unhealthy seeds due to insect attacks are the mostthreatened factors for T. turcica. Healthy seeds obtained from Eber population which is oneof five designated populations of T. turcica were used for germination experiments andmicropropagation. T. turcica seeds were treated with stratification and/or chemicalscarification using concentrated sulfuric, hydrochloric and nitric acids before taken on MSbeads. 90 minute sulfuric acid treatment was optimal for the maximum (%100) and fast (3,6days) germination. However, stratification and other acid treatments were not had an effect onthe germination of T. turcica seeds. Cotyledon, epicotyl and root explants obtained from thesein vitro seedling were transferred on basal MS media containing various concentrations (0.5,1, 2, 4 ve 8 mg/L) of NAA or 2,4-D. Although the best callus formation (%100) was obtainedfrom root explants treated with both 2 mg/L NAA and 2,4-D, only the half biomassdevelopment was determined for calli on basal MS media containing 2,4-D as compared tothe NAA treated explants. Furthermore, adventitious root and shoot developments were onlyobserved during callus formation from the all kinds of explants treated with NAA, but notwith 2,4-D. The shoot formation was only occurred on cytokinine media if the calli?s obtainedin NAA containing media. Therefore, 2,4-D inhibited T. turcica callus formation andregeneration from the callus. The best shoot regeneration (4,4 per callus) was gained with 2mg/L benzyladenine (BA) after the calli?s transferred onto basal MS media including variousconcentrations (0.5, 1 ve 2 mg/L) of benzyladenine (BA) or kinetin. After the regeneratessuccessfully rooted (%70) with basal ½ MS containing 1 mg/L NAA, in vitro T. turcicaseedlings were acclimatized to the soil.Key Words: Thermopsis turcica, endemic, endangered plant species, in vitro germination,micropropagation.