Descripción: A new record for the Argentinean flora, Samanea tubulosa, is described and illustrated. The specimens were collected in Oran, Salta Province, Argentina, in the "Selvas Pedemontanas" district of the "Yungas" phytogeographic province. Comments on the systematic position of the species and related genera are given.

Descripción: Prosopis represents a valuable forest resource in arid and semiarid regions. Management of promising species requires information about genetic parameters, mainly the heritability (h2) of quantitative profitable traits. This parameter is traditionally estimated from progeny tests or half-sib analysis conducted in experimental stands. Such an approach estimates h 2 from the ratio of between-family/total phenotypic variance. These analyses are difficult to apply to natural populations of species with a long life cycle, overlapping generations, and a mixed mating system, without genealogical information. A promising alternative is the use of molecular marker information to infer relatedness between individuals and to estimate h 2 from the regression of phenotypic similarity on inferred relatedness. In the current study we compared h2 of 13 quantitative traits estimated by these two methods in an experimental stand of P. alba, where genealogical information was available. We inferred pairwise relatedness by Ritland's method using six microsatellite loci. Relatedness and heritability estimates from molecular information were highly correlated to the values obtained from genealogical data. Although Ritland's method yields lower h 2 estimates and tends to overestimate genetic correlations between traits, this approach is useful to predict the expected relative gain of different quantitative traits under selection without genealogical information.

Descripción: The base chromosome number of x = 11 is the most probable in all the subtribes included in tribe Phaseoleae, although some aneuploid reduction is evident in Collaea and Galactia (Diocleinae) and chromosome duplications are seen in Amphicarpaea, Cologania and Glycine (Glycininae). The aims of this study were to improve the cytological knowledge of some species of Collaea and Galactia and to examine the anomalous counts reported for Calopogonium (Glycininae) and verify its taxonomic position. In addition, a molecular phylogeny was constructed using nuclear ribosomal DNA sequences (internal transcribed spacer region), and the chromosome number was optimized on the topology. In this work, the chromosome counts for Galactia lindenii, Galactia decumbens and Collaea cipoensis (all 2n = 20), and Calopogonium sericeum (2n = 22) are reported for the first time. The new reports for Galactia and Collaea species are in agreement with the chromosome number proposed for subtribe Diocleinae. The study rejects the concept of a cytologically anomalous Calopogonium and, based on the phylogenetic analysis, corroborates the position of this genus within subtribe Glycininae. The ancestral basic chromosome number of x = 11 proposed for Phaseoleae is in agreement with the evolutionary pathway of chromosome numbers analysed in this work. © 2008 The Linnean Society of London.