The Amazon rain forest sustains the world's highest tree diversity, but it remains unclear why some clades of trees are hyperdiverse, whereas others are not. Using dated phylogenies, estimates of current species richness and trait and demographic data from a large network of forest plots, we show that fast demographic traits--short turnover times--are associated with high diversification rates ...

The phylogenetic relationships among 23 species of the tribe Tigridieae (lridaceae) were inferred using morphological data and nucleotide sequences from nuclear ITS and three intergenic spacers of the cpDNA: psbA-trnH, trnT-trnL, and trnL-trnE Although all data sets supported a monophyletic Mexican-Guatemalan Tigridiinae including two taxa usually placed in Cipurinae ( Cardiostigma longispatha ...

Static headspace analysis of Gabon Estuary okoume (Aucoumea klaineana Pierre) oleoresins indicated that nine products represented the major part (>96%) of the volatile compounds: six monoterpenes (α-pinene, β-pinene, limonene, α-phellandrene, β-phellandrene, 3-carene), one monoterpenic alcohol (α-terpineol) and two other derivatives (p-cymene, eucalyptol). The relative amount of each product ap...

conclusions in this study, phylogenetic reconstruction of hcv-1 sequences clearly indicated for molecular tracing and ancestral relationships of the hcv genotypes in iran, and showed the likelihood of domestic origin for hcv-1a and various origin for hcv-1b. evidence acquisition the phylogenetic analyses were performed based on the nucleotide sequences of ns5b gene of hcv genotype 1 (hcv-1), wh...

Dating of fungal divergences with molecular clocks thus far has yielded highly inconsistent results. The origin of fungi was estimated at between 660 million and up to 2.15 billion y ago, and the divergence of the two major lineages of higher fungi, Ascomycota and Basidiomycota, at between 390 million y and up to 1.5 billion y ago. Assuming that these inconsistencies stem from various causes, w...

evaluating the forest stands structure in different development stages is one of the ways for better understanding the forest dynamics and its response to natural disturbances. this study was carried out in the compartment 319, kheiroud forest in order to quantify the structure properties of mixed beech stands in the stem exclusion phase. for this purpose, three one-hectare sample plots were se...

directional felling of trees plays a key role in reducing of damages to forest residual trees and can also facilitate skidding. the aim of this study was presents a practical linear model for estimation of tree falling direction error in an uneven-aged mixed stand in northern forests of iran. to conduct the study a number of 95 trees of four species fagus orientalis lipsky, carpinus betulus l.,...

A comprehensive effort was devoted to exploring, collecting and characterizing the local Maltese olive germplasm, often represented by ancient, monumental trees plants of uncertain origin. SSR cp-SSR analysis all samples enabled identification 46 genotypes establishment correspondence between ancient trees, main varieties other Mediterranean cultivars. The application plastid markers two lineag...

Algae and plants are the dominant primary producers on our planet and define an evolutionarily diverse group of taxa (Graham and Wilcox 2000). Despite their importance, dating algal origin is frustrated by a limited fossil record (Knoll 1992). Recent molecular phylogenetic trees place algae near the base of the eukaryotic tree of life (e.g., Baldauf et al. 2000, 2003; Nozaki et al. 2003). This ...