Identification of a retroviroid-like element from plants.

The biological nature of carnation small viroid-like RNA (CarSV RNA), a 275-nt circular molecule with self-cleaving hammerhead structures in its strands of both polarities, was investigated. The lack of infectivity observed in a series of transmission assays in carnation indicates that CarSV RNA, in spite of sharing structural similarities with viroid and viroid-like satellite RNAs from plants, does not belong to either of these two groups. Additional evidence in this direction comes from the observation that CarSV RNA also exists in carnation plants as DNA tandem repeats. In this respect, CarSV RNA is similar to a small transcript of a tandemly repeated DNA sequence of the newt genome. Moreover, CarSV and newt RNAs have similarities in their sequences as well as in some characteristics of their corresponding hammerhead structures. Further analyses have revealed that CarSV DNA is found directly fused to DNA sequences of carnation etched ring caulimovirus, a pararetrovirus, most likely in the form of an extrachromosomal element. The properties of the CarSV RNA/DNA system are those of a retroviroid-like element having some features in common with viroid and viroid-like satellite RNAs from plants and others with the newt transcript.

Evolutionary origin of Plasmodium and other Apicomplexa based on rRNA genes.

We have explored the evolutionary history of the Apicomplexa and two related protistan phyla, Dinozoa and Ciliophora, by comparing the nucleotide sequences of small subunit ribosomal RNA genes. We conclude that the Plasmodium lineage, to which the malarial parasites belong, diverged from other apicomplexan lineages (piroplasmids and coccidians) several hundred million years ago, perhaps even before the Cambrian. The Plasmodium radiation, which gave rise to several species parasitic to humans, occurred approximately 129 million years ago; Plasmodium parasitism of humans has independently arisen several times. The origin of apicomplexans (Plasmodium), dinoflagellates, and ciliates may be > 1 billion years old, perhaps older than the three multicellular kingdoms of animals, plants, and fungi. Digenetic parasitism independently evolved several times in the Apicomplexa.

How caterpillar-damaged plants protect themselves by attracting parasitic wasps.

Parasitic and predatory arthropods often prevent plants from being severely damaged by killing herbivores as they feed on the plants. Recent studies show that a variety of plants, when injured by herbivores, emit chemical signals that guide natural enemies to the herbivores. It is unlikely that herbivore-damaged plants initiate the production of chemicals solely to attract parasitoids and predators. The signaling role probably evolved secondarily from plant responses that produce toxins and deterrents against herbivores and antibiotics against pathogens. To effectively function as signals for natural enemies, the emitted volatiles should be clearly distinguishable from background odors, specific for prey or host species that feed on the plant, and emitted at times when the natural enemies forage. Our studies on the phenomena of herbivore-induced emissions of volatiles in corn and cotton plants and studies conducted by others indicate that (i) the clarity of the volatile signals is high, as they are unique for herbivore damage, produced in relatively large amounts, and easily distinguishable from background odors; (ii) specificity is limited when different herbivores feed on the same plant species but high as far as odors emitted by different plant species and genotypes are concerned; (iii) the signals are timed so that they are mainly released during the daytime, when natural enemies tend to forage, and they wane slowly after herbivory stops.

Interactions of maize bushy stunt phytoplasma with the leafhopper vector, Dalbulus maidis (Delong and Wolcott) (Hemiptera: Cicadellidae) and associated microbiota

Phytoplasmas are bacteria with a persistent propagative transmission by insect vectors that generates direct and indirect interactions among them. In order to understand these interactions for maize bushy stunt phytoplasma (MBSP) and the leafhopper vector Dalbulus maidis (Hemiptera: Cicadellidae), two research lines were addressed. The first one aimed to determine the indirect effects of maize infection by MBSP on some biological and behavioral parameters of the vector, whereas a second line investigated direct interactions of the phytoplasma with D. maidis during its movement through the vector body following acquisition from plants, and associated microbiota. Indirect effects were investigated in choice experiments in which alighting and oviposition preferences by D. maidis were compared on healthy vs. MBSP-infected plants with variable incubation time (diseased plants with early and advanced symptoms, or still asymptomatic). Likewise, indirect effect of MBSP on the D. maidis biology was determined in two life table experiments in which the vector was reared on healthy vs. MBSP-infected plants expressing advanced disease symptoms or still asymptomatic. Choice experiments showed that alighting and oviposition preferences of D. maidis on MBSP-infected plants compared to healthy plants depend on the pathogen incubation period in the plant. The leafhopper preferred MBSP-infected plants over healthy ones during the asymptomatic phase of the disease, but rejected infected plants with advanced symptoms. The vector was able to acquire MBSP from asymptomatic infected plants shortly (3 days) after inoculation, but transmission efficiency increased when acquisition occurred at later stages of the pathogen incubation period (≥14 days) in the source plants and the test plants showed disease symptoms faster. These results suggest that MBSP modulates D. maidis preference for asymptomatic infected plants in the early stages of the crop, allowing rapid spread of this pathogen. Maize infection by the phytoplasma had a neutral effect on most life table parameters of D. maidis; a lower net reproductivity rate (Ro) was observed in the cohort reared on MBSP-infected plants with advanced symptoms, which was compensated to some extent by a higher sexual ratio. MBSP acquisition by all vector nymphal stadia was confirmed by PCR, and the pathogen as detected in both male and female reproductive organs. Concerning direct MBSP-vector interactions, transmission electron microscopy analyses showed phytoplasma-like cells in the midgut lumen, microvilli and epithelial cells, suggesting that MBSP enters the epithelium midgut through the microvilli wall. Within the epithelial cells, mitochondria and bacteria-like cells (possibly endosymbionts) were observed together with masses of phythoplasma-like cells. In the hemocoel, phytoplasma-like cells grouped into a matrix were also observed in association with bacteria-like cells similar to those observed in the midgut epithelium. Similar associations were found in the salivary gland. Interestingly, in-situ hybridization (FISH) technique revealed a variation in diversity and abundance of the microbiota in intestine and salivary glands of D. maidis adults over time after MBSP acquisition from plants. Sulcia sp., Cardinium sp. and eubacteria increased their abundance over time, whereas Rickettsia sp. decreased. The frequent association of the vector microbiota with the phytoplasma in some tissues of D. maidis suggests that endosymbiotic bacteria may play some role in MBSP-vector interactions.

Use efficiency of controlled release fertilizer on the growth of croton and petunia and N loss by leaching

The market of flowers and ornamentals such as croton (Codiaeum variegatum) and petunia (Petunia×hybrida Vilm.-Andr) have been created new technologies to constantly development, as one of the most promising segments of horticulture. Fertilization providing adequate nutrition and less leaching to the environment is the objective of numerous studies around the world. Therefore, two studies were conducted to evaluate the use of controlled release fertilizer (CRF) on the growth of two ornamental species, and N loss by leaching. The first experiment aim to evaluate sources and rates of CRF and water soluble fertilizer (WSF) on croton growth and nitrogen concentration on drained solution. Results showed that treatments with WSF and low rates of CRF provided higher plants growth, and the amount of N leached was higher for WSF treatments. The second experiment objective to compare plant performance and cost for strategies that potentially provide adequate nutrition during both the production and consumer phases for container-grown Petunia plants. In addition, two experiments were conducted to evaluate nutrient release in sand containers inside of the greenhouse and under controlled temperature conditions without plants. Results showed that during production phase all fertilizer treatments produced high quality plants, and during consumer phase, plants grown with WSF only during the production phase were nutrient-deficient, while plants receiving CRFs were still growing vigorously, especially in a high rate. The release rates of all CRF products were temperature-dependent. In conclusion CRF provided plant growth at the same rate that WSF, with less N leaching and extra cost less than U$0.065 per plant with CRF during production.

Ethnobotanic importance of plants used in pigeon-breeding in Eastern Spain

Background: The importance that birds of the Columbidae family have had throughout history is visible on the Mediterranean coast. Pigeon fancying is the art of breeding and training carrier pigeons and currently, several breeds exist. The sport of racing pigeons consists in covering a distance at maximum possible speed. However, pigeon breeding has another modality called “sport pigeon”, where several males follow a female. This study focusses on ethnobotanical knowledge of native and exotic plant species that are used for diet, breeding, stimulation, healing illnesses and staining the plumage of pigeons bred in captivity. Methods: Using semi-structured interviews, we gathered information about the different plant species traditionally used for pigeon-breeding in the region of Valencia. Background material on remedies for bird illnesses was gathered from folk botanical references, local books and journals. The plant species were collected in the study area, then identified in the laboratory using dichotomous keys and vouchered in the ABH (Herbarium of Alicante University). We used Excel ® 2003 to perform a simple statistical analysis of the data collected. Results: We collected 56 species of plants (and one variety) that included 29 botanical families. The total number of species was made up of 35 cultivated and 21 wild plants. The most common were Gramineae (14 species), Leguminosae (6 species), and Compositae (4 species). Conclusions: Pigeon breeding is an immensely popular activity in Eastern Spain, and ethnobiological knowledge about breeding pigeons and caring for them is considerable. The names and traditional uses of plants depend on their geographical location, vernacular names serve as an intangible heritage. Feeding, environmental features, and genetic makeup of individuals are relevant aspects in the maintenance of avian health.

Endophytic colonization of barley (Hordeum vulgare) roots by the nematophagous fungus Pochonia chlamydosporia reveals plant growth promotion and a general defense and stress transcriptomic response

Plant crop yields are negatively conditioned by a large set of biotic and abiotic factors. An alternative to mitigate these adverse effects is the use of fungal biological control agents and endophytes. The egg-parasitic fungus Pochonia chlamydosporia has been traditionally studied because of its potential as a biological control agent of plant-parasitic nematodes. This fungus can also act as an endophyte in monocot and dicot plants, and has been shown to promote plant growth in different agronomic crops. An Affymetrix 22K Barley GeneChip was used in this work to analyze the barley root transcriptomic response to P. chlamydosporia root colonization. Functional gene ontology (GO) and gene set enrichment analyses showed that genes involved in stress response were enriched in the barley transcriptome under endophytism. An 87.5 % of the probesets identified within the abiotic stress response group encoded heat shock proteins. Additionally, we found in our transcriptomic analysis an up-regulation of genes implicated in the biosynthesis of plant hormones, such as auxin, ethylene and jasmonic acid. Along with these, we detected induction of brassinosteroid insensitive 1-associated receptor kinase 1 (BR1) and other genes related to effector-triggered immunity (ETI) and pattern-triggered immunity (PTI). Our study supports at the molecular level the growth-promoting effect observed in plants endophytically colonized by P. chlamydosporia, which opens the door to further studies addressing the capacity of this fungus to mitigate the negative effects of biotic and abiotic factors on plant crops.

An ethnopharmacological and historical analysis of “Dictamnus”, a European traditional herbal medicine

Ethnopharmacological relevance and background: “Dictamnus” was a popular name for a group of medicinal herbaceous plant species of the Rutaceae and Lamiaceae, which since the 4th century have been used for gynaecological problems and other illnesses BCE and still appear in numerous ethnobotanical records. Aims: This research has as four overarching aims: Determining the historical evolution of medical preparations labelled “Dictamnus” and the different factors affecting this long-standing herbal tradition. Deciphering and differentiating those medicinal uses of “Dictamnus” which strictly correspond to Dictamnus (Rutaceae), from those of Origanum dictamnus and other Lamiaceae species. Quantitatively assessing the dependence from herbal books, and pharmaceutical tradition, of modern Dictamnus ethnobotanical records. Determining whether differences between Western and Eastern Europe exist with regards to the Dictamnus albus uses in ethnopharmacology and ethnomedicine. Methods: An exhaustive review of herbals, classical pharmacopoeias, ethnobotanical and ethnopharmacological literature was conducted. Systematic analysis of uses reported which were standardized according to International Classification of Diseases – 10 and multivariate analysis using factorial, hierarchical and neighbour joining methods was undertaken. Results and discussion: The popular concept “Dictamnus” includes Origanum dictamnus L., Ballota pseudodictamnus (L.) Benth. and B. acetabulosa (L.) Benth. (Lamiaceae), as well as Dictamnus albus L. and D. hispanicus Webb ex Willk. (Rutaceae), with 86 different types of uses. Between 1000 and 1700 CE numerous complex preparations with “Dictamnus” were used in the treatment of 35 different pathologies. On biogeographical grounds the widespread D. albus is a far more likely prototypical “Dictamnus” than the Cretan endemic Origanum dictamnus. However both form integral parts of the “Dictamnus” complex. Evidence exists for a sufficiently long and coherent tradition for D. albus and D. hispanicus, use to treat 47 different categories of diseases. Conclusions: This approach is a model for understanding the cultural history of plants and their role as resources for health care. “Dictamnus” shows how transmission of traditional knowledge about materia medica, over 26 centuries, represents remarkable levels of development and innovation. All this lead us to call attention to D. albus and D. hispanicus which are highly promising as potential herbal drug leads. The next steps of research should be to systematically analyse phytochemical, pharmacological and clinical evidence and to develop safety, pharmacology and toxicology profiles of the traditional preparations.

Proceedings and transactions of the Liverpool Biological Society.

Mode of access: Internet.

Service and regulatory announcements.

Contains Notices of quarantine and Plant quarantine decisions, formerly issued as separate publications only, now published in both forms.

Energy and society; the relation between energy, social change, and economic development

Mode of access: Internet.

Problems of the future, and essays,

First published in 1889.

[Final report and recommendations]

Cover title.

The rationale of religious enquiry, or, The question stated of reason, the Bible, and the church; in six lectures /

Inspiration -- Catholic infallibility -- Protestant infallibility -- Rationalism -- Relation of natural religion to Christianity -- Influence of Christianity on morality and civilization.

The history of the castle, town, and forest of Knaresbrough : with Harrogate, and it's medicinal springs : including an account of the most remarkable places in the neighbourhood /

Includes index.