Effect of cytokinins on in vitro multiplication, volatiles composition and rosmarinic acid content of Thymus leucotrichus Hal. shoots

Abstract

An efficient in vitro multiplication protocol was designed to , a subshrub and perennial herb growing naturally in the Northwest of Turkey. Of all basal media studied, Murashige and Skoog medium was found to be superior to the others, providing higher shoot formation and the maximum shoot length. Varying concentrations of cytokinins, i.e., 6-benzyladenine, thidiazuron, 2-isopentenyladenine and kinetin were supplemented in the nutrient media to observe their effects on shoot development and biomass. Rosmarinic acid content and volatile compositions of both naturally growing plants and in vitro multiplied plantlets were also evaluated. 6-benzyladenine (1.0 mg/L) and kinetin (0.5 mg/L) were found to be optimum for shoot number and shoot elongation, respectively. Thidiazuron (1.0 mg/L) was superior for biomass production. Rosmarinic acid content of in vitro multiplied plants was found to be higher than that of wild plants, reaching a maximum with 0.5 mg/L 2-isopentenyladenine, which yielded 10.15 mg/g dry weight. The highest thymol content was obtained with 1.0 mg/L kinetin (55.82%), while thidiazuron (0.1 mg/L) increased carvacrol production (12.53%). Overall, Murashige and Skoog medium supplemented with 1.0 mg/L kinetin was determined to be the most favorable medium studied.

Impact of Explants, Plant Growth Regulators and their Interaction on Micropropagation of Impatiens balsamina, L.

“…In addition, cotyledonary node explants was more responsive for shoot regeneration when compared to the other explants and this has been reported previously in Trigonella foenum-graecum L., since a cotyledon node explants has been used for successful shoot regeneration Aasim et al, (2010). The maximum number of shoots was observed on medium fortified with BAP at 4.5 mg/L since it produced (4.33 shoots photo (2a) within 8 weeks followed by (3.16) for medium supplemented with BAP at 3.0 mg/L which showing a gradual increase with higher applications and reaching a maximum at 4.5 mg/l before decreasing at higher concentrations and this were agreement with Bekircan et al, (2018) in Thymus lotocephalus. Also, BAP inhibited shoots elongation at high concentrations and this were agreement with Ashraf et al, (2014) in Chlorophytum borivilianum Sant.…”

An efficient micropropagation protocol for an endangered ornamental tree species (Magnolia sirindhorniae Noot. & Chalermglin) and assessment of genetic uniformity through DNA markers

“…Previous studies also showed that BA induced the maximum response. The superiority of BA over other cytokinins was reported by Hashem, Bekircan and Hussain [36][37][38] . GA 3 contributes to the initiation and elongation of axillary buds as well as leaf expansion; the axillary buds began to grow after five days when GA 3 was added.…”

Modulation of the anatomical and physiological responses of in vitro grown Alcantarea imperialis induced by NAA and residual effects of BAP

“…After in vitro plants have been treated with exogenous CK, they may show a reduced rooting response (Martins et al, 2018b). This is because CKs are plant hormones that influence a wide range of developmental processes, including inhibition of rooting at higher concentrations (Bekircan et al, 2018). In our work, A. imperialis shoots did not require exogenous AUX to ensure the rooting response.…”

“…Two phases are carried out with plant growth regulators (PGRs) such as cytokinins (CKs) and auxins (AUXs), each one performing different physiological functions. CKs are frequently employed during in vitro multiplication and are an important group of PGRs that can modulate several biotechnological processes due to their ability to influence almost all stages of plant development and growth (Bekircan et al, 2018). The most common synthetic CKs used during the in vitro multiplication phase are 6-benzylaminopurine (BAP) and 6-furfurylaminopurine (kinetin -KIN).…”