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Important Genera (important + genus)

Distribution by Scientific Domains
Life Sciences75%

Selected Abstracts

Composition of the volatile oil of Thymus transcaspicus Klokov from Iran

FLAVOUR AND FRAGRANCE JOURNAL, Issue 4 2002
R. Miri
Abstract Thymus is one of the most important genera with regard to the number of species within the family Lamiaceae. The essential oil of Thymus transcaspicus Klokov (Lamiaceae) from Iran was isolated by hydrodistillation in 0.9% yield. The chemical composition of the essential oil was examined by GC and GC,MS. Forty-seven compounds were identified, representing 99.5% of the total oil. The main compounds were thymol (56.4%), ,-terpinene (7.7%), carvacrol (7.6%) and p -cymene (6.3%). Copyright © 2002 John Wiley & Sons, Ltd. [source]

Phylogeny of Macroptilium (Leguminosae): morphological, biochemical and molecular evidence

CLADISTICS, Issue 2 2007
Shirley M. Espert
Macroptilium (Benth.) Urban (Phaseoleae, Papilionoideae, Leguminosae) is an American genus of legumes, belonging to subtribe Phaseolinae along with other economically important genera, such as Vigna Savi and Phaseolus L. (the common bean genus). Cladistic analyses based on morphological, biochemical (storage seed proteins) and molecular (nuclear and plastid DNA sequences) data were performed on the 18 species currently ascribed to the genus, exploring several character weighting strategies. Equal weights, implied weighting and different transversion/transition costs were applied. The three data sets were first analyzed with separate partitions, and then combined into a single matrix. This study is the first one to analyze all the species of the genus from a cladistic point of view. In all the most parsimonious trees obtained, Macroptilium is monophyletic with excellent support values. Two monophyletic clades are recovered in almost all the analyses. Both are compound by nine species, and they constitute two sections of Macroptilium. Several interspecific relationships inside the genus are discussed. © The Willi Hennig Society 2007. [source]

Ovular development and perisperm formation in Phytolacca americana (Phytolaccaceae) and their systematic significance in Caryophyllales

JOURNAL OF SYSTEMATICS EVOLUTION, Issue 5 2010
Hong-Chun ZHENG
Abstract,Phytolacca is the biggest and most original genus in Phytolaccaceae and an important genus in plant systematic studies. Light microscopy results show that the Phytolacca americana L. ovule arises from the caulis (floral receptacle). The perisperm and hypostase are simultaneously initiated from the top several layers of cells of chalaza after fertilization, and the perisperm is located between the nucellus and hypostase. In the early stages of development, the hypostase cells are thin-walled with dense cytoplasm, clear nuclei, and some reserve granules. Later, at the heart-shaped embryo stage, the hypostase cells are dead and thick-walled. The main functions of the hypostase may be to maintain cellular division and perisperm growth without delivering nutrient materials to the perisperm. An evolutionary picture of placentation in Caryophyllales is also presented. [source]

Genotype and time of day shape the Populus drought response

THE PLANT JOURNAL, Issue 4 2009
Olivia Wilkins
Summary As exposure to episodic drought can impinge significantly on forest health and the establishment of productive tree plantations, there is great interest in understanding the mechanisms of drought response in trees. The ecologically dominant and economically important genus Populus, with its sequenced genome, provides an ideal opportunity to examine transcriptome level changes in trees in response to a drought stimulus. The transcriptome level drought response of two commercially important Populus clones (P. deltoides × P. nigra, DN34, and P. nigra × P. maximowiczii, NM6) was characterized over a diurnal period using a 4 × 2 × 2 complete randomized factorial anova experimental design (four time points, two genotypes and two treatment conditions), using Affymetrix Poplar GeneChip microarrays. Notably, the specific genes that exhibited changes in transcript abundance in response to drought differed between the genotypes and/or the time of day that they exhibited their greatest differences. This study emphasizes the fact that it is not possible to draw simple, generalized conclusions about the drought response of the genus Populus on the basis of one species, nor on the basis of results collected at a single time point. The data derived from our studies provide insights into the variety of genetic mechanisms underpinning the Populus drought response, and provide candidates for future experiments aimed at understanding this response across this economically and ecologically important genus. [source]