Understanding 2H/1H systematics of leaf wax n-alkanes in coastal plants at Stiffkey saltmarsh, Norfolk, UK

Interpretation of sedimentary n-alkyl lipid d2H data is complicated by a limited understanding of factors controlling interspecies variation in biomarker 2H/1H composition. To distinguish between the effects of interrelated environmental, physical and biochemical controls on the hydrogen isotope composition of n-alkyl lipids, we conducted linked d2H analyses of soil water, xylem water, leaf water and n-alkanes from a range of C3 and C4 plants growing at a UK saltmarsh (i) across multiple sampling sites, (ii) throughout the 2012 growing season, and (iii) at different times of the day. Soil waters varied isotopically by up to 35& depending on marsh sub-environment, and exhibited site-specific seasonal shifts in d2H up to a maximum of 31 per mil. Maximum interspecies variation in xylem water was 38 per mil, while leaf waters differed seasonally by a maximum of 29 per mil. Leaf wax n-alkane 2H/1H, however, consistently varied by over 100 per mil throughout the 2012 growing season, resulting in an interspecies range in the ewax/leaf water values of -79 per mil to –227 per mil. From the discrepancy in the magnitude of these isotopic differences, we conclude that mechanisms driving variation in the 2H/1H composition of leaf water, including (i) spatial changes in soil water 2H/1H, (ii) temporal changes in soil water 2H/1H, (iii) differences in xylem water 2H/1H, and (iv) differences in leaf water evaporative 2H-enrichment due to varied plant life forms, cannot explain the range of n-alkane d2H values we observed. Results from this study suggests that accurate reconstructions of palaeoclimate regimes from sedimentary n-alkane d2H require further research to constrain those biological mechanisms influencing species-specific differences in 2H/1H fractionation during lipid biosynthesis, in particular where plants have developed biochemical adaptations to water-stressed conditions. Understanding how these mechanisms interact with environmental conditions will be crucial to ensure accurate interpretation of hydrogen isotope signals from the geological record.

The diversity of arbuscular mycorrhizas of selected Australian Fabaceae

Members of the Australian native perennial Fabaceae have been little explored with regard to their root biology and the role played by arbuscular mycorrhizal (AM) fungi in their establishment, nutrition and long-term health. The ultimate goal of our research is to determine the dependency of native perennial legumes on their co-evolved AM fungi and conversely, the impact of AM fungal species in agricultural fields on the productivity of sown native perennial legume pastures. In this paper we investigate the colonisation morphology in roots and the AMF, identified by spores extracted from rhizosphere soil, from three replicate plots of each of the native legumes, Cullen australasicum, C. tenax and Lotus australis and the exotic legumes L. pedunculatus and Medicago sativa. The plants were grown in an agricultural field. The level and density of colonisation by AM fungi, and the frequency of intraradical and extraradical hyphae, arbuscules, intraradical spores and hyphal coils all differed between host plants and did not consistently differ between native and exotic species. However, there were strong similarities between species in the same genus. The three dominant species of AM fungi in rhizosphere soil also differed with host plant, but one fungus (Glomus mosseae) was always the most dominant. Sub-dominant AM species were the same between species in the same genus. No consistent differences in dominant spores were observed between the exotic and native Fabaceae species. Our results suggest that plant host influences the mycorrhizal community in the rhizosphere soil and that structural and functional differences in the symbiosis may occur at the plant genus level, not the species level or due to provenance.

Condensed tannins in extracts from European medicinal plants and herbal products

Medicinal plant materials are not usually analysed for condensed tannins (CT). Thirty commercially available European medicinal plants and herbal products were screened for CT and fourteen CT samples were analysed in detail. This is also the first comprehensive CT analysis of pine buds, walnut leaves, heather flowers and great water dock roots. Acetone/water extracts contained between 3.2 and 25.9 g CT/100 g of extract, had CT with mean degrees of polymerisation of 2.9 to 13.3, procyanidin/prodelphinidin ratios of 1.6/98.4 to 100/0 and cis/trans flavan-3-ol ratios of 17.7/82.3 to 97.3/2.7. The majority of samples contained procyanidins, four contained A-type linkages (blackthorn flowers, heather flowers, bilberry leaves and cowberry leaves) and one sample also had galloylated procyanidins (great water dock roots).

An introductory perspective to horticulture: plants for people and places

Horticulture is “the first of all the arts and sciences”. This definition indicates both the breadth and depth of the discipline and its early inception as mankind changed from being hunter-gatherers to cultivators. Intensive crop production which is a form of horticulture preceded more extensive agricultural practices. From that time onwards the intricate involvement of horticulture in man’s life has become very apparent by its multitude of applications and the interests of those involved. These extend from the provision of foodstuffs and nutritional benefits through pharmaceuticals to aspects of rest and relaxation onto encouraging physical and mental well-being. Horticulture is therefore, a discipline with many components and as such that it can mean different things in the varying context of its use. This chapter introduces the meanings of horticulture as expressed by the authors who have contributed to this Trilogy of Books. They have analysed in considerable depth “Horticulture” as expressed in its facets of production, environment and society. Horticulture has impact and expression in each of these fields of human activity. This chapter also sets Horticulture into the wider context of the world of plants and their intensive cultivation both in their use by mankind and in the natural world. The aim is to demonstrate the depth and breadth of human activity associated with this discipline for it stretches from crop production, through landscape design and maintenance and into aspects of society and its expression in the arts and humanities. Horticulture touches almost every aspect of human activity. Increasingly Horticulture has significant importance in contributing towards the mitigation of the major problems which now face life on Earth such as:- climate change, food security, the loss of natural biodiversity, pollution, resource erosion and over-population. Indeed despite or perhaps because of its antiquity and therefore its strong connection between science, technology and practice horticulture can offer solutions that might allude other disciplines.

A trophic cascade induced by predatory ants in a fig-fig wasp mutualism

Summary 1. A trophic cascade occurs when predators directly decrease the densities, or change the behaviour, of herbivores and thus indirectly increase plant productivity. The predator–herbivore– plant context is well known, but some predators attack species beneficial to plants (e.g. pollinators) and/or enemies of herbivores (e.g. parasites), and their role in the dynamics of mutualisms remains largely unexplored. 2. We surveyed the predatory ant species and studied predation by the dominant ant species, the weaver ant Oecophylla smaragdina, associated with the fig tree Ficus racemosa in southwest China. We then tested the effects of weaver ants on the oviposition behaviour of pollinating and non-pollinating fig wasps in an ant-exclusion experiment. The effects of weaver ants on fig wasp community structure and fig seed production were then compared between trees with and without O. smaragdina. 3. Oecophylla smaragdina captured more non-pollinating wasps (Platyneura mayri) than pollinators as the insects arrived to lay eggs. When ants were excluded, more non-pollinators laid eggs into figs and fewer pollinators entered figs. Furthermore, trees with O. smaragdina produced more pollinator offspring and fewer non-pollinator offspring, shifting the community structure significantly. In addition, F. racemosa produced significantly more seeds on trees inhabited by weaver ants. 4. Oecophylla smaragdina predation reverses the dominance of the two commonest wasp species at the egg-laying stage and favours the pollinators. This behavioural pattern is mirrored by wasp offspring production, with pollinators’ offspring dominating figs produced by trees inhabited by weaver ants, and offspring of the non-pollinator P. mayri most abundant in figs on trees inhabited by other ants. 5. Overall, our results suggest that predation by weaver ants limits the success of the non-pollinating P. mayri and therefore indirectly benefits the mutualism by increasing the reproductive success of both the pollinators and the plant. Predation is thus a key functional factor that can shape the community structure of a pollinator-plant mutualistic system. Key-words: competitive release, fig wasp, mutualism, predation, predator-exclusion experiment, trophic cascade

Physical analyses of compost from composting plants in Brazil

Nowadays the composting process has shown itself to be an alternative in the treatment of municipal solid wastes by composting plants. However, although more than 50% of the waste generated by the Brazilian population is composed of matter susceptible to organic composting, this process is, still today, insufficiently developed in Brazil, due to low compost quality and lack of investments in the sector. The objective of this work was to use physical analyses to evaluate the quality of the compost produced at 14 operative composting plants in the Sao Paulo State in Brazil. For this purpose, size distribution and total inert content tests were done. The results were analyzed by grouping the plants according to their productive processes: plants with a rotating drum, plants with shredders or mills, and plants without treatment after the sorting conveyor belt. Compost quality was analyzed considering the limits imposed by the Brazilian Legislation and the European standards for inert contents. The size distribution tests showed the influence of the machinery after the sorting conveyer on the granule sizes as well as the inert content, which contributes to the presence of materials that reduce the quality of the final product. (C) 2007 Elsevier Ltd. All rights reserved.

The oscillatory bioelectrical signal from plants explained by a simulated electrical model and tested using Lempel-Ziv complexity

This paper demonstrates the oscillatory characteristics of electrical signals acquired from two ornamental plant types (Epipremnum pinnatum and Philodendron scandens - Family Araceae), using a noninvasive acquisition system. The electrical signal was recorded using Ag/AgCl superficial electrodes inside a Faraday cage. The presence of the oscillatory electric generator was shown using a classical power spectral density. The Lempel and Ziv complexity measurement showed that the plant signal was not noise despite its nonlinear behavior. The oscillatory characteristics of the signal were explained using a simulated electrical model that establishes that for a frequency range from 5 to 15 Hz, the oscillatory characteristic is higher than for other frequency ranges. All results show that non-invasive electrical plant signals can be acquired with improvement of signal-to-noise ratio using a Faraday cage, and a simple electrical model is able to explain the electrical signal being generated. (C) 2010 Elsevier B.V. All rights reserved.

Antimicrobial and cytotoxic activities of medicinal plants of the Brazilian cerrado, using Brazilian cachaca as extractor liquid

Ethnopharmacological importance: Many species of plants in the Brazilian cerrado (savanna) are widely used in ethnomedicine. However, the safety and effectiveness of medicinal plants used in communities with little or no access to manufactured drugs should be evaluated. Aim of the study: Evaluate the antimicrobial and cytotoxic activities of extracts from eight plant species, obtained using Brazilian cachaca as the extractor liquid. Materials and methods: The extracts were tested against Bacillus subtilis, Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Candida albicans, Candida parapsilosis, promastigote forms of Leishmania amazonensis, and poliovirus. In addition, cytotoxic activity was assayed in Vero cells and in human erythrocytes. Results: The plant species Curatella americana, Sclerolobium aureum, and Plathymenia reticulata showed the best activity against yeasts, especially the crude extract of C. americana and its ethyl-acetate fraction. Kielmeyera lathrophyton showed a minimum inhibitory concentration of 250 mu g/ml against S. aureus, and was inactive against Gram-negative bacteria. The extract obtained from Annona coriacea showed the best activity against the promastigote forms of Leishmania amazonensis (IC(50) = 175 mu g/ml). Only C. americana showed potential for antipoliovirus activity. The concentrations of the crude extracts that showed toxicity to VERO cells had CC(50) between 31 and 470 mu g/ml, and the lyophilized Brazilian cachaca showed a CC(50) of 307 mu g/ml. None of the extracts showed toxicity against human erythrocytes. Conclusions: Among the plant species studied. C americana proved to be effective against microorganisms, especially as an antifungal. The results will help in the search for alternative drugs to be used in pharmacotherapy, and will contribute to establish safe and effective use of phytomedicines in the treatment of infectious diseases. (C) 2010 Elsevier Ireland Ltd. All rights reserved.

Incidence of Listeria monocytogenes in Cheese Manufacturing Plants from the Northeast Region of Sao Paulo, Brazil

The incidence of Listeria monocytogenes in three cheese manufacturing plants from the northeastern region of Sao Paulo, Brazil, was evaluated from October 2008 to September 2009. L. monocytogenes was found in samples from two plants, at percentages of 13.3% (n = 128) and 9.6% (n = 114). Samples of raw and pasteurized milk, water, and Minas Frescal cheese were negative for L. monocyto genes, although the pathogen was isolated from the surface of Prato cheese and in brine from one of the plants evaluated. L. monocytogenes was also isolated from different sites of the facilities, mainly in non food contact surfaces such as drains, floors, and platforms. Serotype 4b was the most predominant in the plants studied. The results of this study indicate the need for control strategies to prevent the dispersion of L. monocytogenes in the environment of cheese manufacturing plants.

Oculoauriculovertebral spectrum: report of nine familial cases with evidence of autosomal dominant inheritance and review of the literature

Oculoauriculovertebral spectrum (OAVS; OMIM 164210) is a complex condition characterized by defects of aural, oral, mandibular and vertebral development. The aetiology of this condition is likely to be heterogeneous; most cases are sporadic, however, familial cases suggesting autosomal recessive end autosomal dominant inheritance have been reported. In this study, we describe the clinical aspects of nine familial cases with evidence of autosomal dominant inheritance and compare them with reports in the literature. Interfamilial and intrafamilial clinical variabilities were observed in this study (reinforcing the necessity of careful examination of familial members). We suggest that oculoauriculovertebral spectrum with autosomal dominant inheritance is characterized mainly by bilateral auricular involvement and rarely presents extracranial anomalies. Clin Dysmorphol 18:67-77 (C) 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins.