Kinetin

About: Kinetin is a research topic. Over the lifetime, 7856 publications have been published within this topic receiving 135550 citations. The topic is also known as: Kinetin.

Multiple shoot formation in Hypericum perforatum L.and hypericin production

Abstract: Hypericum perforatum is a traditional medicinal plant with wound healing and antidepressive properties. Among the secondary compounds of interest is hypericin, a naphtodianthrone that seems to participate in the medicinal effects of this species. The aim of this work was to obtain an efficient micropropagation system of H. perforatum and to compare the hypericin content between in vitro and field-grown plants. Cultures were initiated from nodal segments of mature plants inoculated onto MS medium supplemented with 4.5 µM BA, kinetin, thidiazuron, individually or in combination with 0.05 µM NAA. Organogenic explants were observed on medium with either BA or kinetin alone or in combination of these with NAA. Subculture of organogenic explants onto the proliferation medium containing 4.5 µM BA promoted the organogenic response. The highest average of shoot production (52.6 shoots) was obtained on those explants induced in the presence of BA and NAA. Rooted plantlets were successfully acclimated. Analysis of hypericin contents showed that levels found in callus represented only 0.11 % of what was detected in adult plants, while shoots and leaves from in vitro plants showed similar hypericin levels to those found in the leaves of the field-grown plants, suggesting that the accumulation of this compound is related to leaf differentiation.

Effects of Kinetin, Gibberellins and (±) Abscisic acid on the Germination of Lettuce (Lactuca sativa)

Abstract: Germination responses of achenes of lettuce (Lactuca sativa L, cv. Arctic King) to treatment with kinetin, gibbe-rellins and abscisic acid were examined over a range of temperatures: in both light and dark. Kinetin (0.1–10 mg/l) strongly promoted germination at temperatures above 27±C in continuous light or after short periods of illumination during the early stages of imbibition. It also relieved the inhibitory affects of abscisic acid in these conditions. In total darkness however kinetin treatment resulted in only a minor promotive effect. Treatment with gibberellic acid (A3) or a mixture of gibberellins A4 and A7 were much less effective in promoting germination at higher temperatures of lettuce achenes exposed to light but were strongly promotive in the dark.

Activity of antioxidant enzyme during in vitro organogenesis in Crocus sativus

Abstract: The effect of various hormonal combinations on regeneration of shoots and roots from meristem-derived callus of Crocus sativus L. and activities of antioxidant enzymes have been studied. The most efficient regeneration occurred with 1.0 mg dm−3 1-naphthaleneacetic acid (NAA) + 1.0 mg dm−3 thidiazuron and 1.0 mg dm−3 NAA + 2.0 mg dm−3 kinetin. For sprouting, regenerated shoot were subcultured on Murashige and Skoog medium containing 1.0 mg dm−3 NAA + 1.0 mg dm−3 benzylaminopurine (BAP). Protein content and superoxide dismutase activity decreased in regenerated shoots and roots and increased in sprouting shoots, while catalase (CAT), peroxidase (POX) and polyphenol oxidase (PPO) activities increased during organogenesis and decreased in sprouting shoots. High CAT and PPO activities were detected in regenerated roots, whereas high POX activity was observed in regenerated shoot.

Adventitious root induction in Ophiorrhiza prostrata: a tool for the production of camptothecin (an anticancer drug) and rapid propagation

Abstract: Roots of Ophiorrhiza prostrata D. Don serve as a rich source of camptothecin (CPT), an anticancer drug. Because of the large-scale collection of its roots, the plant has become a threatened species. The present study accomplishes the induction of adventitious roots as a means for the production of CPT as well as for the large-scale propagation of this anticancer drug plant using leaf and internode explants. The biomass yield and CPT content of adventitious roots induced from different explants were compared to roots developed on ex vitro rooted stem cuttings. Adventitious roots were produced on half-strength Murashige and Skoog (MS) medium supplemented with 10.74 μM α-naphthaleneacetic acid and 2.32 μM kinetin at mean fresh weights of 0.753, 0.739 and 0.748 g roots from leaf, internode and shoot, respectively. CPT yield from in vitro derived roots after 50, 80 and 120 days of incubation (0.028, 0.06 and 0.1% dry weight, respectively) was not significantly different from those harvested at the same age from ex vitro rooted (0.03, 0.06 and 0.13%, respectively) stem cuttings. CPT from subcultured roots derived from solid (0.08%) medium was lower than from suspension culture medium (0.12%). Subsequent cultures of the adventitious roots showed a stable production of CPT (0.16%). The yield of CPT from 360-day-old plant-derived roots was 0.19%. Elicitation using methyl jasmonate and acetyl salicylic acid exhibited no enhancement in CPT yield. In vitro propagation through direct shoot regeneration was achieved from the adventitious roots upon transfer to MS medium with 8.87 μM N6-benzyladenine (BA) and 2.46 μM indole-3-butyric acid (IBA) with a mean of 21.2 shoots per culture in 50 days. The shoots upon subculture on medium having the same level of BA and IBA underwent rapid proliferation. The shoots transferred to field conditions after in vitro rooting exhibited 95% survival. Adventitious root induction, from leaf and internode explants, enables the feasible production of CPT as well as the large-scale rapid propagation of this species which can safeguard it from extinction.