Optimization of in vitro seed germination of Taraxacum platycarpum

Abstract

Dandelion (Taraxacum platycarpum) has been widely utilized for medicinal purposes. However, the dandelion seeds are relatively difficult to germinate under cultivation conditions, which hampers seedling propagation of dandelion plants and reduces the opportunity of usage of such a useful medicinal plant. Thus, in this study, in vitro conditions for the dandelion seed germination were optimized to enhance the germination rate. In seed washing steps, the sequential treatments with 20% of ethanol, 20% of NaOCl, and distilled water avoided microbial contamination with the highest in vitro germination rate (67.5%) from seeds sown in germination media. The media supplemented with 1.4 g/L of MS salts and 1% of sucrose significantly enhanced the germination rate compared to the media with 4.4 g/L of MS and 3% of sucrose. Sowing the seeds vertically in the optimized media supplement conditions, 1.4 g/L of MS salts and 1% of sucrose, gave the maximum in vitro germination rate (61%), which was almost three times higher than sowing seeds on a soil pot (23%). Our results indicate that the seed washing and sowing methods including germination medium supplements can be optimized to enhance in vitro seed germination of dandelion.

Assessment of Plant Growth Regulators and Carbon Sources on the Germination and Growth Process of Dandelion (Taraxacum officinale G.H. Weber ex Wiggers) under In Vitro Conditions

“…The osmotic effect varies directly with the presence of compounds present in the culture medium, mainly salts and sugars, the concentration of which determines the availability of water. It has been indicated that high sugar concentrations delay germination and generate abnormal seedlings [4], which is consistent with the observations of this work when high carbon SUC concentrations were studied (3.2 and 5.5%). However, the effect of sugars on germination is not only related to the osmotic pressure, since in tests with other purely osmotic compounds the response on germination is different [30,31], but both sugars modulate critical plant processes such as germination when they interact with phytohormones and PGRs [32,33].…”

“…This was the result of having performed the experiment in an agar matrix instead of the traditional wet disc paper on a Petri dish or in soil pots; therefore, gas and mass transfer interactions need to be considered. Only one work reported the use of an agar matrix for T. platycarpum seed germination [4] with FGP values in agreement with those obtained in this study. However, another study in soil indicates 60% of germination for this species, so the difference between agar matrix and soil, might be important but not conclusive.…”

“…Recently, some authors studied the effect of SUC on Taraxacum platycarpum germination, in which FGP was 50-65% and 30-40% at 1.0% and 3.0% of the carbon source, respectively, and depending on whether the seeds were sowed vertically or horizontally [4]. Because MS concentration was different for both conditions proposed, no direct correlation with the results at 1.0% and 3.0% could be further established.…”

“…However, its germination process has been usually studied concerning the natural colonization in meadows and to eradicate it from industrial crops, and scarce information regarding dandelion seed requirements is available. The germination of dandelion seeds (Taraxacum officinale) in natural conditions (for instance, in open fields) is low, probably due to pathogenic infections or physical/physiological damage, which makes seedling establishment difficult, finally reducing the opportunity of using this species commercially as a medicinal plant [4]. Few studies have been performed to understand Taraxacum germination, improve in vitro techniques and achieve a better propagation process.…”

Effect of Seed Orientation and Medium Strength on <i>In vitro</i> Germination of <i>Pterocarpus marsupium</i> Roxb.

“…Keeping in view low germination and difficulties in establishment of seedling due to pathogens, in vitro germination of P. marsupium can be utilized as an essential prerequisite for production en masse. Ahmad et al (2012) used MS, B5 (Gamborg et al, 1968) and White (1963) medium for in vitro seed germination of Pterocarpus marsupium without considering the seed orientation, which is an important and key factor for in vitro (Lee et al, 2009) and ex vitro (Swaminathan et al, 1993;Bhat, 2011) seed germination. Besides, they did not produce any plant through in vitro method.…”