Transcriptomic analysis of Enterohaemorrhagic Escherichia coli O157:H7 in response to plant extracts

Enterohaemorrhagic Escherichia coli (EHEC) are a group of food and contact-borne pathogens responsible for haemorrhagic colitis. The bacteria can be transmitted by contaminated meat, but importantly, also by plants. The bacteria can use plants as an alternative host, where they associate with both the leaves and the roots. Colonisation in the rhizosphere of plants is thought to be the main habitat for colonisation. Four different plant species, commonly associated with EHEC outbreaks, were infected with EHEC O157:H7 isolates Sakai and TUV 93-0 over ten days to assess the colonisation potential of the bacteria in both the phyllosphere and rhizosphere of plants. The rhizosphere was found to sustain a higher population level of bacteria over time in comparison to the phyllosphere, yet both strains were unable to utilize root exudates for growth. Global gene expression changes of EHEC O157:H7 strain Sakai were measured in response to plant extracts such as leaf lysates, root exudates and leaf cell wall polysaccharides from spinach cultivar Amazon and lettuce cultivar Salinas. Microarrays analysis showed a significant change in expression of 17 % of genes on exposure to leaf lysates of spinach. A more specific response was seen to spinach leaf cell wall polysaccharides with only a 1.5 % change. In contrast, when exposed to lettuce leaf cell wall polysaccharides a higher change of 4.8 % was seen. Genes that were differentially expressed belonged to multiple functional groups, including metabolism, indicating the utilization of plant-specific polysaccharides. Several areas of further investigation have been determined from this project, including the importance of culturing bacterial strains at a relevant temperature, the proposed lack of the type III secretion system in plant colonization by EHEC O157:H7 and the utilization of plant components for growth and persistence in the plant environment.

Piriformospora indica reduces Fusarium head blight disease severity and mycotoxin DON contamination in wheat under UK weather conditions

Piriformospora indica (Sebacinaceae) is a cultivable root endophytic fungus. It colonises the roots of a wide range of host plants. In many settings colonisation promotes host growth, increases yield and protects the host from fungal diseases. We evaluated the effect of P. indica on Fusarium head blight (FHB) disease of winter (cv. Battalion) and spring (cv. Paragon, Mulika, Zircon, Granary, KWS Willow and KWS Kilburn) wheat and consequent contamination by the mycotoxin deoxynivalenol (DON) under UK weather conditions. Interactions of P. indica with an arbuscular mycorrhizal fungus (Funneliformis mosseae), fungicide application (Aviator Xpro) and low and high fertiliser levels were considered. P. indica application reduced FHB disease severity and incidence by 70%. It decreased mycotoxin DON concentration of winter and spring wheat samples by 70% and 80% respectively. P. indica also increased above ground biomass, 1000 grain weight and total grain weight. P. indica reduced disease severity and increased yield in both high and low fertiliser levels. The effect of P. indica was compatible with F. mosseae and foliar fungicide application. P. indica did not have any effects on plant tissue nutrients. These results suggest that P. indica might be useful in biological control of Fusarium diseases of wheat.

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.

An assessment of the effects of climate change on horticulture

Horticulture may be defined as the intensive cultivation and harvesting of plants for financial, environmental and social profit. Evidence for the occurrence of climate change more generally and reasons why this process is happening with such rapidity are discussed. These changes are then considered in terms of the effects which might alter the options for worldwide intensive horticultural cultivation of plants and its interactions with other organisms. Potentially changing climates will have considerable impact upon horticultural processes and productivity across the globe . Climate change will alter the growth patterns and capabilities for flowering and fruiting of many perennial and annual horticultural plants. In some regions perennial fruit crops are likely to experience substantial difficulties because of altered seasonal conditions affecting dormancy, acclimation and subsequent flowering and fruiting. Elsewhere these crops may benefit from the effects of climate change as a result of reduced cold damage and increased length of the growing season. There will be considerable effects for aerial and edaphic microbes invertebrate and vertebrate animals which have benign and pathogenic interactions with horticultural plants. Microbial activity and as a consequence soil fertility may alter. New pests and pathogens may become prevalent and damaging in areas where the climate previously excluded their activity. Vital resources such as water and nutrients may become scarce in some regions reducing opportunities for growing horticultural crops. Wind and windiness are significant factors governing the success of horticultural plants and the scale of their impacts may change as climate alters. Damaging winds could limit crop growing in areas where previously it flourished. Forms of macro- and micro-landscaping will change as the spectrum of plants which can be cultivated alters and the availability of resources and their cost changes driven by scarcities brought about by climate change. The horticultural economy of India as it may be affected by climate change is described as an individual example in a detailed study.

1,8-cineol potentiates IRF3-mediated antiviral response in human stem cells and an ex vivo model of rhinosinusitis

Common cold is one of the most frequent human inflammatory diseases caused by viruses and can facilitate bacterial super-infections resulting in sinusitis or pneumonia. The active ingredient of the drug Soledum, 1,8-cineole, is commonly applied for treating inflammatory diseases of the respiratory tract. However, the potential of 1,8-cineole for treating primary viral infections of the respiratory tract remains unclear. In the present study, we demonstrate for the first time that 1,8-cineole potentiates Poly(I:C)-induced activity of the anti-viral transcription factor Interferon Regulatory Factor 3, while simultaneously reducing pro-inflammatory NF-κB-activity in human cell lines, inferior turbinate stem cells (ITSCs) and ex vivo cultivated human nasal mucosa. Co-treatment of cell lines with Poly(I:C) and 1,8-cineole resulted in significantly increased IRF3 reporter gene activity compared to Poly(I:C) alone, whereas NF-κB-activity was reduced. Accordingly, 1,8-cineole- and Poly(I:C)-treatment led to increased nuclear translocation of IRF3 in ITSCs and a human ex vivo model of rhinosinusitis compared to the Poly(I:C)-treated approach. Nuclear translocation of IRF3 was significantly increased in ITSCs and slice cultures treated with LPS and 1,8-cineole compared to the LPS-treated cells mimicking bacterial infection. Our findings strongly suggest that 1,8-cineole potentiates the antiviral activity of IRF3 in addition to its inhibitory effect on pro-inflammatory NF-κB-signalling and may thus broaden its field of application.

Dark-induced hormone changes coincide with the resumption of light-inhibited shoot growth in Catasetum fimbriatum (Orchidaceae)

Catasetum fimbriatum plants cultivated in the absence of light exhibit continuous shoot growth leading to the formation of nodes and internodes. On the other hand, when these plants are incubated in the presence of light, shoot longitudinal growth is inhibited and pseudobulbs develop just below the shoot apical meristem. These facts provide evidence of a possible influence of light on mitotic cell division in the shoot apex as well as on pseudobulb initiation. The effects of light and dark on the interruption and/or maintenance of shoot apex mitotic activity and the subsequent formation of pseudobulbs in the sub-meristematic regions were investigated by means of histological and hormonal studies. The interruption of shoot apex development occurred around the 150th d of light incubation and seems to have resulted from the establishment of a strong storage sink in the region of the future pseudobulb, in detriment to the continuous activity of the shoot apical meristem. The reduced total cytokinins/IAA ratio in the apex, mainly due to high levels of IAA, could be a key factor in the interruption of cell divisions. Transfer to the dark brings about the resumption of shoot apex development of plants through the re-entrance of cells in the cell cycle which coincides with a significant increase in the total cytokinins/IAA ratio. (C) 2009 Elsevier GmbH. All rights reserved.

How does a riverine setting affect the lifestyle of shellmound builders in Brazil?

The contact of inland and coastal prehistoric groups in Brazil is believed to have been restricted to regions with no geographical barrier, as is the case in the Ribeira de Iguape valley. The inland osteological collection from the riverine shellmound Moraes (5800-4500 BP) represents a unique opportunity to test this assumption for this region. Despite cultural similarities between riverine and coastal shellmounds, important ecological and site distribution differences are expected to impact on lifestyle. The purpose of this study is thus to document and interpret health and lifestyle indicators in Moraes in comparison to coastal shellmound groups. Specifically we test if the rare evidence of fish and mollusc remains in the riverine shellmound led to (a) higher caries rates and (b) lower auditory exostosis frequency and (c) if the small size of the riverine shellmound translates into reduced demographic density and thus rarity of communicable infectious diseases. Of the three hypotheses, (a) was confirmed, (b) was rejected and (c) was partly rejected. Bioanthropological similarities between Moraes and coastal shellmounds include auditory exostoses with equally high frequencies; significantly more frequent osteoarthritis in upper than in lower limbs; cranial and dental morphological affinities and low frequencies of violent trauma. However, there are also important differences: Moraes subsisted on a much broader protein diet and consumed more cariogenic food, but showed a stature even shorter than coastal groups. Thus, despite the contact also suggested by treponematoses in both site types, there was enough time for the people at the riverine site to adapt to local conditions. (c) 2008 Elsevier GmbH. All rights reserved.

Efficient but destructive: a test of the dental wash technique using secondary electron microscopy

The Boyadjian et al dental wash technique provides, in certain contexts, the only chance to analyze and quantify the use of plants by past populations and is therefore an important milestone for the reconstruction of paleodiet. With this paper we present recent investigations and results upon the influence of this method on teeth. A series of six teeth from a three thousand years old Brazilian shellmound (Jabuticabeira II) was examined before and after dental wash. The main focus was documenting the alteration of the surfaces and microstructures. The status of all teeth were documented using macrophotography, optical light microscopy, and atmospheric Secondary Electron Microscopy (aSEM) prior and after applying the dental wash technique. The comparison of pictures taken before and after dental wash showed the different degrees of variation and damage done to the teeth but, also, provided additional information about microstructures, which have not been visible before. Consequently we suggest that dental wash should only be carried out, if absolutely necessary, after dental pathology, dental morphology and microwear studies have been accomplished. (C) 2010 Elsevier Ltd. All rights reserved.

Eugenol modifies the excitability of rat sciatic nerve and superior cervical ganglion neurons

Eugenol is a phenylpropene obtained from the essential oils of plants such as clove and basil which has ample use in dentistry. Eugenol possesses analgesic effects that may be related to the inhibition of voltage-dependent Na(+) channels and/or to the activation of TRPV1 receptors or both. In the present study, electrophysiological parameters were taken from the compound action potentials of the isolated rat sciatic nerve and from neurons of the superior cervical ganglion (SCG) impaled with sharp microelectrodes under current-clamp conditions. In the isolated rat sciatic nerve, eugenol inhibited the compound action potential in a concentration-dependent manner. Action potentials recorded from SCG neurons were inhibited by eugenol with an IC(50) of 0.31 mM. At high concentrations (2 mM), during brief applications. eugenol caused significant action potential blockade while it did not interfere with the resting membrane potential or the membrane input resistance. Surprisingly, however, at low eugenol concentrations (0.6 mM), during long time applications, a reversible reduction (by about 50%) in the input membrane resistance was observed, suggesting the possible involvement of a secondary delayed effect of eugenol to reduce neuronal excitability. (C) 2010 Elsevier Ireland Ltd. All rights reserved.

Separation and Execution of graphical engine on a cross platform IDE to enhance performance

“Biosim” is a simulation software which works to simulate the harvesting system.This system is able to design a model for any logistic problem with the combination of several objects so that the artificial system can show the performance of an individual model. The system will also describe the efficiency, possibility to be chosen for real life application of that particular model. So, when any one wish to setup a logistic model like- harvesting system, in real life he/she may be noticed about the suitable prostitution for his plants and factories as well as he/she may get information about the least number of objects, total time to complete the task, total investment required for his model, total amount of noise produced for his establishment in advance. It will produce an advance over view for his model. But “Biosim” is quite slow .As it is an object based system, it takes long time to make its decision. Here the main task is to modify the system so that it can work faster than the previous. So, the main objective of this thesis is to reduce the load of “Biosim” by making some modification of the original system as well as to increase its efficiency. So that the whole system will be faster than the previous one and performs more efficiently when it will be applied in real life. Theconcept is to separate the execution part of ”Biosim” form its graphical engine and run this separated portion in a third generation language platform. C++ is chosenhere as this external platform. After completing the proposed system, results with different models have been observed. The results show that, for any type of plants of fields, for any number of trucks, the proposed system is faster than the original system. The proposed system takes at least 15% less time “Biosim”. The efficiency increase with the complexity of than the original the model. More complex the model, more efficient the proposed system is than original “Biosim”.Depending on the complexity of a model, the proposed system can be 56.53 % faster than the original “Biosim”.

Automating condition monitoring of vegetation on railway trackbeds and embankments

Vegetation growing on railway trackbeds and embankments present potential problems. The presence of vegetation threatens the safety of personnel inspecting the railway infrastructure. In addition vegetation growth clogs the ballast and results in inadequate track drainage which in turn could lead to the collapse of the railway embankment. Assessing vegetation within the realm of railway maintenance is mainly carried out manually by making visual inspections along the track. This is done either on-site or by watching videos recorded by maintenance vehicles mainly operated by the national railway administrative body. A need for the automated detection and characterisation of vegetation on railways (a subset of vegetation control/management) has been identified in collaboration with local railway maintenance subcontractors and Trafikverket, the Swedish Transport Administration (STA). The latter is responsible for long-term planning of the transport system for all types of traffic, as well as for the building, operation and maintenance of public roads and railways. The purpose of this research project was to investigate how vegetation can be measured and quantified by human raters and how machine vision can automate the same process. Data were acquired at railway trackbeds and embankments during field measurement experiments. All field data (such as images) in this thesis work was acquired on operational, lightly trafficked railway tracks, mostly trafficked by goods trains. Data were also generated by letting (human) raters conduct visual estimates of plant cover and/or count the number of plants, either on-site or in-house by making visual estimates of the images acquired from the field experiments. Later, the degree of reliability of(human) raters’ visual estimates were investigated and compared against machine vision algorithms. The overall results of the investigations involving human raters showed inconsistency in their estimates, and are therefore unreliable. As a result of the exploration of machine vision, computational methods and algorithms enabling automatic detection and characterisation of vegetation along railways were developed. The results achieved in the current work have shown that the use of image data for detecting vegetation is indeed possible and that such results could form the base for decisions regarding vegetation control. The performance of the machine vision algorithm which quantifies the vegetation cover was able to process 98% of the im-age data. Investigations of classifying plants from images were conducted in in order to recognise the specie. The classification rate accuracy was 95%.Objective measurements such as the ones proposed in thesis offers easy access to the measurements to all the involved parties and makes the subcontracting process easier i.e., both the subcontractors and the national railway administration are given the same reference framework concerning vegetation before signing a contract, which can then be crosschecked post maintenance.A very important issue which comes with an increasing ability to recognise species is the maintenance of biological diversity. Biological diversity along the trackbeds and embankments can be mapped, and maintained, through better and robust monitoring procedures. Continuously monitoring the state of vegetation along railways is highly recommended in order to identify a need for maintenance actions, and in addition to keep track of biodiversity. The computational methods or algorithms developed form the foundation of an automatic inspection system capable of objectively supporting manual inspections, or replacing manual inspections.

Expressão de uma quitinase de Metarhizium anisopliae em Nicotiana tabacum : obtenção de plantas transgênicas resistentes a doenças fúngicas

A resistência a doenças em plantas transgênicas tem sido obtida por meio da expressão de genes isolados de bactérias, fungos micoparasitas e plantas. Neste trabalho, relatamos a utilização de um gene do fungo entomopatogênico Metarhizium anisopliae como modo de gerar resistência a doenças fúngicas em plantas. O gene chit1 codifica a quitinase CHIT42 (EC 3.2.1.14), pertencente a uma classe de glicosil-hidrolases capazes de converter quitina em oligômeros de N-acetil-glicosamina (NAcGlc). Quando presentes em tecidos vegetais, supõese que as quitinases ataquem especificamente a parede celular de fungos invasores, provocando danos às hifas e causando a morte por lise das células fúngicas. Deste modo, dois diferentes grupos de plantas transgênicas de Nicotiana tabacum foram produzidos: no primeiro deles, denominado chitplus, os indivíduos possuem o gene chit1 sob o controle do promotor CaMV 35S. O segundo grupo, demoninado chitless, consiste de plantas transformadas com um T-DNA não contendo o gene do fungo. Trinta e quatro plantas transgênicas resistentes à canamicina (17 de cada grupo) foram regeneradas a partir de discos de folhas infectados por Agrobacterium tumefaciens. A produção da quitinase em extratos protéicos de folhas foi analisada por zimogramas em SDS-PAGE contendo glicol-quitina e corados por calcoflúor branco, na forma de um screening dos transgênicos primários. As plantas transgênicas foram testadas, ainda, por meio de ensaios colorimétricos empregando oligômeros sintéticos de NAcGlc como substratos específicos, além de immunoblot e Western blot com soro anti-quitinase. A quantidade de enzima recombinante nas plantas chitplus variou desde nenhuma atividade detectável a elevados níveis de expressão da enzima. A hibridização de Southern blot demonstrou que o número de cópias do gene chit1 integradas no genoma vegetal foi estimado entre uma e quatro. A primeira geração de plantas transgênicas geradas por autofecundação de parentais portadores de duas cópias do transgene foi testada com relação à estabilidade da herança do transgene e em 43 de um total de 67 descendentes, originados de quatro cruzamentos independentes, o padrão de segregação não diferiu das proporções Mendelianas esperadas. Ensaios de resistência, desafiando as plantas transgênicas com o basidiomiceto Rhizoctonia solani foram realizados e uma evidente diminuição da área foliar contendo lesões fúngicas foi observada entre as linhagens transgênicas, embora variações na atividade quitinolítica tenham influenciado o nível de resistência. Nossos resultados sugerem uma relação direta entre a atividade específica de quitinase e ao aumento nos níveis de resistência às lesões causadas pela infecção por R. solani.

Substrate Preparation Behaviors for the Cultivation of the Symbiotic Fungus in Leaf-Cutting Ants of the Genus Atta (Hymenoptera: Formicidae)

Our findings revealed two distinct patterns of substrate preparation: the pattern of leaf-cutting ants foraging on dicotyledons is marked by highly fragmented substrate resulting in a more advanced initial decomposition. The pattern of leaf-cutting ants harvesting grasses is characterized by large pieces of substrate, resulting in little initial decomposition. Ants foraging on both types of plants are apparently intermediary between the two patterns, although more similar to the patterns of those foraging on dicotyledons. Also, the behavior of scraping the substrate was described for the first time, it is very important for the removal of the epicuticular wax layer of the leaves helping the growth of the symbiotic fungus.

Comportamento de cultivares de manga (Mangifera indica L.) em relação à malformação

A malformação da mangueira causada pelo fungo Fusarium subglutinans Wollenweb & Reinking é provavelmente a doença que mais causa prejuízos à produção de manga no Brasil e em outros países produtores. Esse fungo foi isolado de uma planta-matriz da cultivar Tommy Atkins com avançados sintomas da doença, purificado e preparado para ser inoculado em 15 cultivares de manga nacionais e importadas. Inicialmente, foram inoculadas, em julho de 2000, 10 cultivares: Bourbon IAC - 100, Coração-de-Boi, Keitt, Parvin, Primor de Amoreira, Sensation, Smith, Surpresa, Tommy Atkins e Van Dyke. O segundo grupo foi inoculado em dezembro de 2000, com as cultivares: Adams, Bhadauran, Palmer, Princesa e Zill, e repetiu-se a inoculação com outras mudas das cultivares Primor de Amoreira, Sensation e Tommy Atkins, com a finalidade de se compararem as duas épocas de inoculação. Através dos dados obtidos com as plantas avaliadas nas duas épocas de inoculação, após 11 meses de observações, realizou-se o teste de médias Z para comparar a proporção de plantas doentes entre as cultivares, podendo-se concluir, com os resultados obtidos, que as cultivares Bhadauran, Palmer, Parvin, Sensation, Surpresa, Van Dyke e Zill apresentam menor porcentagem de plantas com sintomas de malformação ou menor progressão de sintomas em relação às outras cultivares inoculadas, para as condições de ambiente protegido em que foram realizados os ensaios.

Produção de mudas de maracujazeiro-amarelo por enxertia hipocotiledonar sobre sete espécies de passifloras

The yellow passion fruit (Passiflora edulis Sims f. flavicarpa Deg.) Passifloraceae is the main crop in Brazil, and the crop has found some difficulties, particularly concerned to the orchards longevity, which has been reduced due to diseases and nematodes that attack the root system. This study was carried out to establish technologies for the production of seedlings of yellow passion fruit by hypocotyledonary grafting on seven rootstocks. The treatments used as rootstocks were: P. edulis f. flavicarpa, P. caerulea, P. alata, P. giberti, P. coccinea, P. cincinnata and P. setacea. The experimental design was completely randomized, with 36 replications for each rootstock. The percentage of graft survival, plant height, number of leaves and rootstock diameter were the characteristics evaluated. The hypocotyledonary grafting methodology was successful for most species tested. P. caerulea, P. giberti, P. cincinnata and P. flavicarpa were the stood out rootstocks by their high conditions of plants growth, and by their early plants production.