The Effects of Different Media, Sucrose Concentrations and Natural Additives on Plantlet Growth of Phalaenopsis Hybrid 'Pink'

ABSTRACT The effects of various sucrose concentrations as carbon source and natural additives in different media on plantlet growth of Phalaenopsis hybrid 'Pink' were studied. Plantlets were cultured on two media (Murashige and Skoog [MS] and Vacin and Went [VW]) supplemented with 0, 10, 20, 30 and 40 g L-1 sucrose either with 0, 10 and 20% (v/v) coconut water (CW) or carrot juice (CJ) as natural additives. After four months of culture, the combination of sucrose and CW supplemented with both media affected plantlet growth where most of the plantlets showed slow growth and survival frequency (0-80%) with increasing concentrations of CW in all sucrose concentrations. However, plantlet growth on both media containing only 20 g L-1 sucrose without CW was optimal in terms of root number, root length, leaf number, leaf length, leaf width, fresh weight, dry weight and plant height. The combination of sucrose and CJ supplemented with MS medium resulted in overall good plantlet growth with 100% survival frequency. The combination of sucrose (20 g L-1) and CJ (10%) supplemented with MS medium increased root length, leaf length, leaf width and plant height. Plantlet growth was also optimal in the combination of 20 g L-1 sucrose and 10% CJ supplemented with VW medium. The results of this study indicate that Phalaenopsis hybrid 'Pink' cultured on the combination of sucrose (20 g L-1) and CJ (10%) supplemented with either MS or VW media can be used for plantlet growth of this species

Effect of plant growth regulators on the growth and direct shoot formation from leaf explants of the hybrid Phalaenopsis ‘Pink’

Phalaenopsis orchids are one of the most beautiful flowering plants. The objective of this study was to identify the best plant growth regulator combination and medium for the growth and direct shoot formation from leaf explants of the hybrid Phalaenopsis ‘Pink’. Leaf tips segments from in vitro young plants were cultured on half-strength Murashige and Skoog (MS) and Vacin and Went (VW) media supplemented with different concentrations of auxin [α-napthaleneacetic acid (NAA)] and cytokinins [6-benzylaminopurine (BAP) or thidiazuron (TDZ)]. The explants that were cultured on 0 mg l–1 NAA and 3 mg l–1 BAP supplemented to half-strength MS medium formed shoots successfully within 10 weeks of culture with 5 % regenerants and 50 % survival frequency. The explants cultured on 0.5 mg l–1 NAA and 1.5 mg l–1 TDZ supplemented to half-strength MS medium developed calluses and shoots within 11 weeks of culture with 25 % regenerants and 90 % survival frequency. Future research needs to be directed to find out the shortest time of shoot regeneration to produce viable plants with a high survival frequency.</p

Dendrogram of the genetic distance among 29 <i>Amorphophallus paeoniifolius</i> populations using unrooted neighbor joining.

<p>The bar shows genetic distance.</p

Inflorescence and cultivation of <i>Amorphophallus paeoniifolius</i>.

<p>(A) Inflorescence of elephant foot yams at anthesis. (B) Rough petiole of <i>A</i>. <i>paeoniifolius var</i>. <i>sylvestris</i>; the corm is considered less palatable in Lombok-Indonesia. (C) A large plant in Rayong Province, Thailand. (D) Semi-wild plants in an abandoned farm in Lombok-Indonesia. (E) Growing plants in an open lowland field in Kerala state, India.</p

Population structure of elephant foot yams (<i>Amorphophallus paeoniifolius</i> (Dennst.) Nicolson) in Asia

<div><p>The corms and leaves of elephant foot yams (<i>Amorphophallus paeoniifolius</i> (Dennst.) Nicolson) are important foods in the local diet in many Asian regions. The crop has high productivity and wide agroecological adaptation and exhibits suitability for the agroforestry system. Although the plant is assumed to reproduce via panmixia, a comprehensive study on the genetic background across regions to enhance wider consumer palatability is still lacking. Here, ten informative microsatellites were analyzed in 29 populations across regions in India, Indonesia and Thailand to understand the genetic diversity, population structure and distribution to improve breeding and conservation programs. The genetic diversity was high among and within regions. Some populations exhibited excess heterozygosity and bottlenecking. Pairwise <i>F</i>_<i>ST</i> indicated very high genetic differentiation across regions (<i>F</i>_<i>ST</i> = 0.274), and the Asian population was unlikely to be panmictic. Phylogenetic tree construction grouped the populations according to country of origin with the exception of the Medan population from Indonesia. The current gene flow was apparent within the regions but was restricted among the regions. The present study revealed that Indonesia and Thailand populations could be alternative centers of the gene pool, together with India. Consequently, regional action should be incorporated in genetic conservation and breeding efforts to develop new varieties with global acceptance.</p></div

Summary of 10 microsatellite loci across populations of elephant foot yam, <i>Amorphophallus paeoniifolius</i> (Dennst.) Nicolson.

<p>Summary of 10 microsatellite loci across populations of elephant foot yam, <i>Amorphophallus paeoniifolius</i> (Dennst.) Nicolson.</p

Phylogenetic tree among 29 <i>Amorphophallus paeoniifolius</i> populations from India, Indonesia and Thailand using 1,000 bootstrap replicates.

<p>The bar shows the genetic distance. The MED and WEST populations were considered out groups from the Indonesian and Indian populations, respectively.</p

Study sites in India, Indonesia and Thailand.

<p>Filled dots denote study sites; provinces or islands are shown in insets; and numbers in an inset denote sampling sites. Bold lines are possible routes of gene flow. See <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0180000#pone.0180000.s002" target="_blank">S1 Table</a> for the population codes and site descriptions.</p