Morphological and RAPD-marker characterization of Melia volkensii (Grke) in vitro plants regenerated via direct and indirect somatic embryogenesis

Abstract

Somaclonal variation induced in vitro during tissue culture can be a problem in clonal micropropagation of elite plants. This study investigated the extent of morphological and genetic similarity or dissimilarity between Melia volkensii in vitro plants (somatic seedlings) obtained via somatic embryogenesis and normal seedlings. Comparisons were made between in vitro plants regenerated directly from cotyledon explants, indirectly from zygotic embryos and normal seedlings of the same parent trees. Regeneration was achieved using half MS medium supplemented with 0.05 mg/l thidiazuron. Shoots were elongated in half MS with 0.1 mg/l BAP plus 0.01 mg/l IAA then rooted in half MS with 0.1 mg/l IBA and 0.1 mg/l NAA. Six morphometric and five meristic characters were used for the morphological characterization. PCR-RAPD markers were used for assessment of genetic similarity or distance. Multivariate analysis using principal coordinates, cluster analysis, analysis of similarities (Anosim) and similarity percentages analysis (SIMPER) revealed significant dissimilarities (p< 0.0001) in morphometric and meristic characters between the in vitro plants and normal seedlings. However, significant similarity (p<0.01) was observed in the RAPD-genic characters of the in vitro plants and normal seedlings. Out of six morphometric traits, taproot length, internode length and shoot height were the most important sources of dissimilarity, cumulatively accounting for 72.37% of overall morphometric dissimilarity. Number of lateral roots was the single most important source of meristic dissimilarity, with 77.02% contribution. Plants regenerated directly from cotyledons were more similar to the normal seedlings in morphological and RAPD-marker characters than those regenerated indirectly from zygotic embryos. This study paves the way for identification of trait-specific RAPD markers for further characterization through sequence-characterized amplified regions (SCARs).

Morphological, molecular and resistance responses to soft-rot disease variability among plantlets of Phalaenopsis amabilis regenerated from irradiated protocorms

“…Therefore, the early indicators for the existence of somaclonal variation are important to commercial plant growers. Fortunately, some of the observed phenotypic variants among the regenerated plantlets in tissue culture propagated planting materials are controlled by epigenetics (Miguel and Marum 2011;Mulanda et al 2015;Park et al 2009;Smulders and Klerk 2011;Us-Camas et al 2014). We found some phenotypic variations such as leaf shape and leaf apex shape in the plantlet from irradiated protocorm in the present results.…”

“…Somaclonal variation may be undesirable in micropropagation through in vitro techniques (Hammerschlag et al 1992;Taylor et al 1995;Biswas et al 2009;Miguel and Marum 2011;Mulanda et al 2015;Park et al 2009;Smulders and Klerk 2011;Us-Camas et al 2014). Therefore, the early indicators for the existence of somaclonal variation are important to commercial plant growers.…”

Comparative Study of the Genetic and Biochemical Variability of Polyscias filicifolia (Araliaceae) Regenerants Obtained by Indirect and Direct Somatic Embryogenesis as a Source of Triterpenes

“…In addition, the plant material should be analyzed at the genetic level to identify changes in DNA sequence. However, as changes in the regenerant genome may also occur following changes in the level of DNA methylation, these should also be confirmed using methylation-sensitive markers [15,21,34,35].…”

“…Sample purification was performed by solid phase extraction (SPE) according to the method presented by [35]. Chromabond SB (Macherey-Nagel, Düren, Germany) polypropylene columns with a bed weight of 500 mg and a capacity of 6 mL were used.…”

Evaluación de un sistema de regeneración por embriogénesis somática de Neem (Azadirachta indica)

“…No obstante, De Oliveira et al (2015) en Carapa guianensis plantean una elevada frecuencia caulogénica (sin indicar el porcentaje) empleando de 1-10 mg.L -1 de 2,-4-D con 1.1 mg.L -1 de BAP. En el caso de los cotiledones, el desarrollo de callos regenerativos que se describe en su mayoría es de tipo embriogénico, así, en el caso del callo caulogénico o con brotes, se induce entre un 87 y 100 % con 1.1 mg.L -1 de BAP y 1 mg.L -1 ANA en Cedrela fissilis (Nunes et al, 2002), mientras que el callo nodular compacto o embriogénico se desarrolla en un 80 % utilizando 3 mg.L -1 de 2,4-D con 3 mg.L -1 ANA en Melia azedarach (Deb, 2001) y con solo 0.05 a 1 mg.L -1 de tidiazuron en Melia volkensii (Mulanda et al, 2014;Mulanda et al, 2015), potenciándose el desarrollo de callo con embriones somáticos secundarios en un 68 % con 1.6 mg.L -1 de TDZ en Semecarpus anacardium (Panda y Hazea, 2012) o 61 % con 0.7 mg.L -1 de ANA en Sorbus pohuashanensis (Yang et al, 2012). Por último, en secciones nodales o esquejes se desarrollaron 85% de callos con brotes con solo 0.5 mg.L -1 de BAP en Melia dubia (Ram et al, 2014).…”