Showing papers on "Maranta published in 2012"

Molecular Phylogeny and Redefined Generic Limits of Calathea (Marantaceae)

Abstract: Calathea, with an estimated 285 species, is the largest genus of Marantaceae and an important component of Neotropical herbaceous diversity. The genus is also of high importance for horticulture as species are cultivated for their showy, patterned leaves. Previous molecular phylogenetic studies indicated that the genus is polyphyletic, but have not provided a basis for redefining generic limits due to incomplete taxon sampling. To address this problem we analyzed DNA sequence data from three plastid markers (matK with flanking 30 trnK intron, trnL intron and trnL-trnF intergenic spacer) and one nuclear marker (ITS) under a maximum parsimony criterion for a large and representative taxon sample covering all previously proposed infrageneric entities, and representing the full range of morphological variation known in the genus. Our results confirm that Calathea is polyphyletic. One clade, including subgenus Calathea ,t heC. lanicaulis group, and the genus Sanblasia, is sister to a clade formed by Ischnosiphon and Pleiostachya .T he genusMonotagma is placed as sister to this clade. The remaining species form a second strongly supported clade as sister to a clade containing these other genera. Based on these findings Calathea is recircumscribed in a narrow sense and Sanblasia is placed in synonymy. The genus Goeppertia is resurrected and redefined to include all members of the second Calathea clade. Morphological characters defining each genus are provided. A total of 246 new combinations are made. Keywords—Goeppertia, ITS, matK, maximum parsimony, Sanblasia, trnL-F region. Marantaceae, with approximately 550 species, is the sec- ond largest family in the Zingiberales. The family is particu- larly diverse in the Neotropics where it is represented by an estimated 450 species. Phylogenetic studies at the family level (Andersson and Chase 2001; Prince and Kress 2006a) have shown Neotropical diversity to primarily involve two large groups: the Maranta clade with nine genera and ca. 70 species is concentrated in southeastern Brazil; and the Calathea clade with five genera and ca. 370 species is distrib- uted throughout the Neotropics but with highest diversity in northwestern South America. Within the Calathea clade, Calathea G. Mey. is by far the largest genus with an esti- mated 300 species (Andersson 1998). Govaerts and Kennedy (2012) list 285 accepted names. These numbers clearly make Calathea the largest genus in the family. The genus is also important for horticulture as indoor plants and in tropical garden landscaping due to their variegated leaves with spots or bands of white, orange, or red, and often bright purple underside. Several species have been used as model organisms for studies of reproductive ecology, plant phys- iology, and demography (e.g. Kennedy 1978; Horvitz and Schemske 2002; Clasen-Bockhoff and Heller 2008; Matlaga and Sternberg, 2009; Swenson 2009; Maron et al. 2010). Other

Morphological, Structural, and Functional Properties of Maranta(Maranta arundinacea L) Starch.

Abstract: Starch isolated from maranta (Maranta arundinacea) tuber and studied for its various physicochemical characteristics. The amylose content of the starch was 24.8%. SEM showed that the granules were small indented and spherical. Maranta starch granule size has a range of 2.92–6.42 μm, (mean of 4.84 μm), length/degree of 1.20, and roundness of 0.73. Maranta starch has a gelatinization temperature of 74.8°C, peak viscosity of 498 BU, and cold paste viscosity of 669 BU. It also possessed higher freeze-thaw stability. Dynamic rheological properties of maranta starch, measured using parallel plate geometry showed increased storage modulus (G’) values, while loss modulus (G″) values were decreased with increasing frequency values (0–100 Hz). The low gelatinization temperature and high freeze thaw stability of starch indicates its potential for application as a thickener in food industries.