In vitro germination and callus induction of Corchorus olitorius L.

Corchorus olitorius L. is a species of high economic importance due to its use as a fiber plant in many parts of the world. The species is also used as a vegetable and condiment and has medicinal properties due to the active ingredients it contains. Within the scope of this thesis, firstly, the effects of nutrient media, physical state of the media, light and gibberellic acid on the in vitro germination of the seeds of the species were investigated. Secondly, the effect of different types and concentrations of plant growth regulators on callus induction and the appropriate explant type were investigated. With the tetrazolium test applied to the seeds, the viability rate of the seeds was determined as 80%. DS, Agar, MS (Murashige and Skoog (1962)) (liquid) and MS (solid) media were used to determine the effect of the type and physical of the nutrient media on in vitro germination. The highest in vitro germination value was determined as 68.86% in DS medium. The plantlets obtained through in vitro germination were cultured on MS medium solidified with 8 gl-1 agar. Cotyledons were isolated one week after the initiation of culture, while leaves were isolated 4-6 weeks after the initiation of culture and used as explants for callus induction. Callus formation was stimulated in both types of explants, and the obtained callus rates were different from one another. A callus value of 100% was achieved from cotyledon explants in culture media supplemented with 10 mgl-1 NAA, 5 mgl-1 NAA and 1 mgl-1 BA under both dark and photoperiod conditions. Additionally, the highest callus value was observed at dark conditions with 1 mgl-1 2,4-D. In leaf explants, 100% callus induction was also achieved using combinations of auxins and cytokinins, particularly with 10 mgl-1 NAA, 5 mgl-1 NAA and 1 mgl-1 BA. Leaf explants showed higher callus rates compared to cotyledon explants, and in both explant types, the effective auxin was identified as NAA. The high rates achieved in both germination and callus induction studies, along with the first successful callus induction using leaf explants reported in the literature, highlight this study's potential not only for genetic improvement efforts with the species but also as a pioneering approach for in vitro studies targeting the extraction of medicinal compounds present in its leaves.