The systematic relationships of glucosinolate-producing plants and related families: a cladistic investigation based on morphological and molecular characters

A cladistic analysis is performed using 94 morphological and biochemical characters for 42 genera to compare a phylogeny based on morphological data with those obtained using different genes ( rbc L, atp B, 18S RNA, mat K) or their combination with morphological data, and to understand the floral evolution within the expanded Brassicales (Capparales) relative to Sapindales and Malvales. The tree produced with morphological data is congruent with those obtained from macromolecular studies in obtaining a well-supported glucosinolate-producing clade and an expanded Sapindales. The combined analysis of the morphological and molecular characters is generally well resolved with support for many of the relationships. The inclusion of the fossil taxon Dressiantha demonstrates the value of inserting fossil evidence in phylogenetic analyses. However, the fossil appears to be related to the Anacardiaceae and not to the Brassicales. The core Brassicales are well supported by a number of synapomorphies, although the internal position of Tovariaceae and Pentadiplandraceae is not well resolved. Emblingiaceae appears to be related to Bataceae and Salvadoraceae. Several significant morphological characters are mapped on the combined trees and their evolutionary significance is discussed. Within Brassicales and Sapindales several well supported clades can be recognized which merit ordinal or subordinal status, putting the present orders at a higher level; these include: Tropaeolales, Setchellanthales, Batidales, Brassicales (Brassiciflorae), Burserales, Sapindales and Rutales (Sapindiflorae). The present scheme of affinities within the Brassicales corresponds well with a gradual morphological evolution in the order.  © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society , 2006, 151 , 453–494.     

Food and humidity affect sex pheromone ratios in the stink bug, Euschistus heros

Abstract.  Male stink bugs, Euschistus heros , only produce the three-component sex pheromone blend consisting of methyl-(2 E ,4 Z )-decadienoate, methyl-2,4,6-trimethyldodecanoate and methyl-2,4,6-trimethyltridecanoate in a constant ratio of 53 : 3 : 44, respectively, when provided with a food source (green beans, Phaseolus vulgaris ). When volatiles are collected from insects with drinking water, humidified air, or under dry conditions, the insects stop producing two components (methyl-2,4,6-trimethyldodecanoate and methyl-2,4,6-trimethyltridecanoate) after 1 day and increase the amount of defensive compounds produced [e.g. ( E )-2-hexenal, decane]. Methyl-2,4,6-trimethyltridecanoate is able to change the behaviour of females but not males. Dual-choice olfactometer bioassays with synthetic standards of all three components, as well as the ternary mixture in the correct ratio, induce a response from females but not males, indicating that all three components have a role in sexual communication. Thus, the dietary conditions under which volatile collections are carried out are crucial for determination of the precise sex pheromone blend.     

Characterization of methanogenic and prokaryotic assemblages based on mcrA and 16S rRNA gene diversity in sediments of the Kazan mud volcano (Mediterranean Sea)

The diversity of the methyl‐coenzyme reductase A (mcrA) and 16S rRNA genes was investigated in gas hydrate containing sediment from the Kazan mud volcano, eastern Mediterranean Sea. mcrA was detected only at 15 and 20 cm below seafloor (cmbsf) from a 40‐cm long push core, while based on chemical profiles of methane, sulfate, and sulfide, possible anaerobic oxidation of methane (AOM) depth was inferred at 12–15 cmbsf. The phylogenetic relationships of the obtained mcrA, archaeal and bacterial 16S rRNA genes, showed that all the found sequences were found in both depths and at similar relative abundances. mcrA diversity was low. All sequences were related to the Methanosarcinales, with the most dominant (77.2%) sequences falling in group mcrA‐e. The 16S rRNA‐based archaeal diversity also revealed low diversity and clear dominance (72.8% of all archaeal phylotypes) of the Methanosarcinales and, in particular, ANME‐2c. Bacteria showed higher diversity but 83.2% of the retrieved phylotypes from both sediment layers belonged to the δ‐Proteobacteria. These phylotypes fell in the SEEP‐SRB1 putative AOM group. In addition, the rest of the less abundant phylotypes were related to yet‐uncultivated representatives of the Actinobacteria, Spirochaetales, and candidate divisions OP11 and WS3 from gas hydrate‐bearing habitats. These phylotype patterns indicate that AOM is occurring in the 15 and 20 cmbsf sediment layers.     

Secretory hairs in Gentiana and allied genera (Gentianaceae, subtribe Gentianinae) from the Iberian Peninsula

Eleven species from six different sections of the genus Gentiana , as well as one species each of genera Gentianella (G. campestris), Gentianopsis (G. ciliata), Comastoma (C. tenellum) and Swertia (S. perennis) have been studied by light microscopy for the presence of hairs in floral as well as in vegetative parts. Hairs are produced in the calyx and vegetative leaves of all of them, and also in the corollae of the last three species. They fall into two different types: those found in the corolla of Gentianopsis ciliata are non-secretory, while in the rest of the species studied, and also in the calyx and leaves of G. ciliata , they produce a mucilaginous secretion. Calycine and foliar hairs are always produced in the adaxial epidermis at the base of the foliar organ, and are considered as mucilage secreting colleters. The presence of colleters in vegetative organs has not been adequately considered in previous taxonomic accounts, in spite of their presumed significance.     

Shoot P status regulates cluster-root growth and citrate exudation in Lupinus albus grown with a divided root system

The present study was carried out to investigate whether the P concentration in the roots or the shoots controls the growth and citrate exudation of cluster roots in white lupin (Lupinus albus L). Foliar P application indicated that low P concentration in the shoots enhanced cluster‐root growth and citrate‐exudation rate more so than low P concentration in the roots. In the split‐root study, the P concentration in the shoots increased with increased P supply (1, 25 or 75 mmol m^?3 P), to the ‘privileged’ root halves. Roots ‘deprived’ of P invariably had the same low P concentrations, whereas those in the ‘privileged’ roots increased with increasing P supply (1, 25 or 75 mmol m^?3 P). Nevertheless, the proportion of the total root mass allocated to cluster roots, and the citrate‐exudation rates from the root halves were always similar on both root halves, irrespective of P supply, and decreased with increasing shoot P concentrations. Peak citrate exudation rates from developing cluster roots were significantly faster from cluster roots on the ‘deprived’ root halves when the ‘privileged’ half was exposed to 1 mmol m^?3 P as compared with 25 or 75 mmol m^?3 P. The possibility that changes in the concentrations of P fractions in the root halves influenced cluster‐root growth and citrate exudation was discounted, because there were no significant differences in insoluble organic P, ester‐P and inorganic P among all ‘deprived’ root halves. The results indicate that cluster‐root proportions and citrate exudation rates were regulated systemically by the P status of the shoot, and that P concentrations in the roots had little influence on growth and citrate exudation of cluster roots in L. albus.