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The present study reports, for the first time, an efficient in vitro plant regeneration protocol for Digitalis ferruginea subsp. ferruginea L. (rusty foxglove). We have used different concentrations of gibberellic acid (GA 3 ) on Murashige and Skoog (MS) medium to assess the germination frequency of seeds. High frequency of germination was achieved on MS medium with 1.0 mg l -1 GA 3 . 6-Benzylaminopurine (BAP) combined with a-naphtaleneacetic acid (NAA) or 2, 4-dichlorophenoxy acetic acid (2, 4-D) in the induction MS medium induced both somatic embryogensis and shoot organogenesis. The highest percentage of callus growth (85 %) was obtained when hypocotyl explants were cultured on MS medium containing 0.5 mg l -1 2, 4-D plus 1.0 mg l -1 BAP. The maximum mean number of somatic embryos (7.3 ± 1.3 embryos) or shoots (12.0 ± 1.1 shoots) per callus was obtained when medium contained 0.25 mg l -1 NAA plus 1.0 mg l -1 BAP or 0.5 mg l -1 NAA plus 2.0 mg l -1 BAP. The regenerated shoots easily rooted on MS medium. Higher amounts of lanatoside C [13.2 ± 0.5 mg 100 g -1 dry weight (dw)] and digoxin (2.93 ± 0.31 mg 100 g -1 dw) accumulation were obtained when shoots were obtained by indirect regeneration. We also investigated derivatives of cardenolides, i.e., digitoxigenin (730 ± 180 mg 100 g -1 dw), gitoxigenin (50 ± 20 mg 100 g -1 dw) and digoxigenin (490 ± 170 mg 100 g -1 dw) from natural samples.

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The adverse effects of high temperature stress can be alleviated by thermotolerance induced by exogenous application of plant growth regulators or by gradual application of temperature stress. Physalis peruviana L., commonly known as the Cape gooseberry, is a source of a variety of phytocompounds such as withanolides (withanone, withaferin A, and withanolide A). These withanolides are potentially high-value drug candidates because of their various pharmacological properties. The production of withanolides via traditional agriculture is commercially inadequate. In the present study, elicitation strategies were employed to improve the crop's thermotolerance and accumulation of withanolides. For these purposes, the effects of heat acclimation (45 °C HA) or salicylic acid (150 mM SA) treatments in inducing withanolide production and thermotolerance were tested in leaves of P. peruviana L. grown under high temperature stress (55 °C). Considerable increases in the production of withanolides (up to 86.83 mg g-1 dry weight, dw) were observed when the cultures were exposed for 5 h to high temperature stress after pretreatment with SA. SA application and heat acclimation increased the activity of superoxide dismutase (SOD; EC 1.15.1.1) and decreased the catalase activity (CAT; EC 1.11.1.6). Both SA and heat acclimation caused a significant increase in endogenous H 2 O 2 and proline content. Changes in related antioxidants paralleling heat acclimation or SA treatment suggest that common mechanisms might be involved in thermotolerance induced by SA and heat acclimation.

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Einkorn is one of the oldest and important wheat species because of its increasing economic value, agronomical technical properties, and health and sanitary effects. Therefore, a faster tissue culture production protocol which may ensure a fast einkorn production is desired. The tissue culture process first requires an efficient sterilization technique of the explant to eliminate contamination factors in this hulled species. In this study, we, thus, aimed to determine the effective einkorn sterilization process for the removal of contaminating microorganisms without the loss of germination capacity and viability. We tested 22 following sterilant combinations with different concentration and exposure time: Ethanol, Commercial Bleach, Tween 20, Mercury (II) Chloride, and Sterile Distilled Water. On the other hand, obtained the data were analyzed by one-way ANOVA and Duncan test, where p≤0.05 was accepted significant. Forty percent commercial bleach which were applied fifteen minutes eliminated all microorganisms with a 92.6% seed germination. The second-best technique was one minute exposure of 70% ethanol which were followed by 10 minutes exposure of 20% commercial bleach. This assured up to 89% germination and no contamination. The worst results came from the mercury (II) chloride with 0% contamination and ≤ 25% germination rate. Mercury (II) Chloride was both highly toxic on the seeds and reduced the contamination. Commercial Bleach and Ethanol Chemicals were less toxic while providing an acceptable sterilization.