Grunwald N.J.,U.S. Department of Agriculture |
Garbelotto M.,University of California at Berkeley |
Goss E.M.,University of Florida |
Heungens K.,Belgium Institute for Agricultural and Fisheries Research |
Prospero S.,Swiss Federal Institute of forest
Trends in Microbiology | Year: 2012
The recently emerged plant pathogen Phytophthora ramorum is responsible for causing the sudden oak death epidemic. This review documents the emergence of P. ramorum based on evolutionary and population genetic analyses. Currently infection by P. ramorum occurs only in Europe and North America and three clonal lineages are distinguished: EU1, NA1 and NA2. Ancient divergence of these lineages supports a scenario in which P. ramorum originated from reproductively isolated populations and underwent at least four global migration events. This recent work sheds new light on mechanisms of emergence of exotic pathogens and provides crucial insights into migration pathways. © 2012.
Cornille A.,CNRS Ecology, Systematic and Evolution Laboratory |
Cornille A.,University Paris - Sud |
Giraud T.,CNRS Ecology, Systematic and Evolution Laboratory |
Giraud T.,University Paris - Sud |
And 4 more authors.
Trends in Genetics | Year: 2014
The cultivated apple is a major fruit crop in temperate zones. Its wild relatives, distributed across temperate Eurasia and growing in diverse habitats, represent potentially useful sources of diversity for apple breeding. We review here the most recent findings on the genetics and ecology of apple domestication and its impact on wild apples. Genetic analyses have revealed a Central Asian origin for cultivated apple, together with an unexpectedly large secondary contribution from the European crabapple. Wild apple species display strong population structures and high levels of introgression from domesticated apple, and this may threaten their genetic integrity. Recent research has revealed a major role of hybridization in the domestication of the cultivated apple and has highlighted the value of apple as an ideal model for unraveling adaptive diversification processes in perennial fruit crops. We discuss the implications of this knowledge for apple breeding and for the conservation of wild apples. © 2013 Elsevier Ltd.
Agency: GTR | Branch: BBSRC | Program: | Phase: Research Grant | Award Amount: 17.43K | Year: 2014
Abstracts are not currently available in GtR for all funded research. This is normally because the abstract was not required at the time of proposal submission, but may be because it included sensitive information such as personal details.
Stals A.,Ghent University |
Van Coillie E.,Belgium Institute for Agricultural and Fisheries Research |
Uyttendaele M.,Ghent University
Current Opinion in Virology | Year: 2013
Food borne viruses such as norovirus and hepatitis A virus are increasingly recognized worldwide as the most important cause of food borne gastro-intestinal illness. Food borne outbreaks, often involving multiples cases, have been reported and associated with food products of both animal and non-animal origin. Most foods are contaminated with food borne viruses during preparation and service. However, bivalve molluscs and occasionally produce (in particular leafy vegetables and soft red fruits) may be contaminated during production and processing. Owing to the low infectious dose of these viruses, the presence of few viral particles on the food is often sufficient for an infection. Over the past decade, molecular methods-such as RT-(q)PCR-have therefore been developed for rapid detection of viral contamination on foods. The availability of these detection methods has led to an increased detection of viral contamination in foods. However, RT-(q)PCR and other molecular methods detect the mere presence of an RNA (or DNA) fragment and are unable to differentiate between infectious and non-infectious viral particles in the monitoring of food products for viral contamination which makes interpretation of these results not straightforward. The current review aims to summarize recent efforts made for a more correct interpretation of these positive RT-(q)PCR results. First of all, RT-(q)PCR test results should be analyzed taking into account the results of various appropriate controls in place to assure well-functioning of good laboratory practices. Subsequently, approaches that may aid to facilitate acceptation and that may aid to put RT-(q)PCR positive food products into context from a public health perspective are discussed. These approaches include (1) the use of a critical acceptance limit, (2) the confirmation of positive RT-(q)PCR results and (3) the potential correlation with faecal indicators. Finally, the current review provides insights in a selection of methods currently under development that may be able to facilitate the specific detection of infectious food borne viruses. © 2012 Elsevier B.V.
Huyghebaert G.,Belgium Institute for Agricultural and Fisheries Research |
Ducatelle R.,Ghent University |
Immerseel F.V.,Ghent University
Veterinary Journal | Year: 2011
Livestock performance and feed efficiency are closely interrelated with the qualitative and quantitative microbial load of the animal gut, the morphological structure of the intestinal wall and the activity of the immune system. Antimicrobial growth promoters have made a tremendous contribution to profitability in intensive husbandry, but as a consequence of the increasing concern about the potential for antibiotic resistant strains of bacteria, the European Commission decided to ban all commonly used feed antibiotics. There are a number of non-therapeutic alternatives, including enzymes, (in)organic acids, probiotics, prebiotics, etheric oils and immunostimulants. Their efficacy and mode of action are briefly described in this review. © 2010 Elsevier Ltd.
De Schepper V.,Ghent University |
De Swaef T.,Ghent University |
De Swaef T.,Belgium Institute for Agricultural and Fisheries Research |
Bauweraerts I.,Ghent University |
Steppe K.,Ghent University
Journal of Experimental Botany | Year: 2013
It is generally believed that an osmotically generated pressure gradient drives the phloem mass flow. So far, this widely accepted Münch theory has required remarkably few adaptations, but the debate on alternative and additional hypotheses is still ongoing. Recently, a possible shortcoming of the Münch theory has been pointed out, suggesting that the Münch pressure flow is more suitable for herbs than for trees. Estimation of the phloem resistance indicates that a point might be reached in long sieve tubes where the pressure required to drive the Münch flow cannot be generated. Therefore, the relay hypothesis regained belief as it implies that the sieve tubes are shorter then the plant's axial axis. In the source phloem, three different loading strategies exist which probably result from evolutionary advantages. Passive diffusion seems to be the most primitive one, whereas active loading strategies substantially increase the growth potential. Along the transport phloem, a leakage-retrieval mechanism is observed. Appreciable amounts of carbohydrates are lost from the sieve tubes to feed the lateral sinks, while a part of these lost carbohydrates is subsequently reloaded into the sieve tubes. This mechanism is probably involved to buffer short-term irregularities in phloem turgor and gradient. In the long term, the mechanism controls the replenishment and remobilization of lateral stem storage tissues. As phloem of higher plants has multiple functions in plant development, reproduction, signalling, and growth, the fundamental understanding of the mechanisms behind phloem transport should be elucidated to increase our ability to influence plant growth and development. © The Author 2013. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: email@example.com.
Foque D.,Belgium Institute for Agricultural and Fisheries Research |
Nuyttens D.,Belgium Institute for Agricultural and Fisheries Research
Pest Management Science | Year: 2011
BACKGROUND: Fewer plant protection products are now authorised for use in ornamental growings. Frequent spraying with the same product or a suboptimal technique can lead to resistance in pests and diseases. Better application techniques could improve the sustainable use of the plant protection products still available. Spray boom systems-instead of the still predominantly used spray guns-might improve crop protection management in greenhouses considerably. The effect of nozzle type, spray pressure and spray angle on spray deposition and coverage in ivy pot plants was studied, with a focus on crop penetration and spraying the bottom side of the leaves in this dense crop.RESULTS: The experiments showed a significant and important effect of collector position on deposition and coverage in the plant. Although spray deposition and coverage on the bottom side of the leaves are generally low, they could be improved 3.0-4.9-fold using the appropriate application technique.CONCLUSIONS: When using a spray boom in a dense crop, the nozzle choice, spray pressure and spray angle should be well considered. The hollow-cone, the air-inclusion flat-fan and the standard flat-fan nozzle with an inclined spray angle performed best because of the effect of swirling droplets, droplets with a high momentum and droplet direction respectively. © 2010 Society of Chemical Industry Copyright © 2010 Society of Chemical Industry.
Fiems L.O.,Belgium Institute for Agricultural and Fisheries Research
Animals | Year: 2012
Molecular biology has enabled the identification of the mechanisms whereby inactive myostatin increases skeletal muscle growth in double-muscled (DM) animals. Myostatin is a secreted growth differentiation factor belonging to the transforming growth factor-β superfamily. Mutations make the myostatin gene inactive, resulting in muscle hypertrophy. The relationship between the different characteristics of DM cattle are defined with possible consequences for livestock husbandry. The extremely high carcass yield of DM animals coincides with a reduction in the size of most vital organs. As a consequence, DM animals may be more susceptible to respiratory disease, urolithiasis, lameness, nutritional stress, heat stress and dystocia, resulting in a lower robustness. Their feed intake capacity is reduced, necessitating a diet with a greater nutrient density. The modified myofiber type is responsible for a lower capillary density, and it induces a more glycolytic metabolism. There are associated changes for the living animal and post-mortem metabolism alterations, requiring appropriate slaughter conditions to maintain a high meat quality. Intramuscular fat content is low, and it is characterized by more unsaturated fatty acids, providing healthier meat for the consumer. It may not always be easy to find a balance between the different disciplines underlying the livestock husbandry of DM animals to realize a good performance and health and meat quality. © 2010 by the authors; licensee MDPI, Basel, Switzerland.
Vleugels T.,Belgium Institute for Agricultural and Fisheries Research
Communications in agricultural and applied biological sciences | Year: 2011
Sclerotinia trifoliorum causes clover cancer in red clover crops. Clover cancer is difficult to control and completely resistant red clover varieties are not available. Breeding for resistant red clover varieties is being slowed down because little is known about the diversity of European S. trifoliorum populations and because of the lack of bio-tests that are useable in breeding programs. The first objective of this research was to develop a reliable high-throughput bio-test, useable in breeding programs. The second objective was to optimise another bio-test, based on isolated leaves, for more precise studies. First, we optimised a method for ascospore production of S. trifoliorum. Once produced, the ascospores were used to evaluate the effects of climate conditions, ascospore concentration and plant age on the high-throughput bio-test. For the bio-test on isolated leaves, the effects of infection method, incubation conditions, incubation period, ascospore concentration, leaf growth stage and mechanical damage were evaluated. In the high-throughput bio-test, disease levels rose with increasing ascospore concentration up to 20,000 spores/ml. The plant age had a small, yet significant effect on the disease level. For the isolated leaf bio-test, the most effective and most repeatable infection method was spraying of an ascospore suspension. Disease levels continued to increase with rising concentrations and incubation time did not interact with plant susceptibility levels. The youngest completely opened leaf yielded the most repeatable results. Both bio-tests were shown to be correlated and could be valuable instruments for breeding programs and for studying plant-pathogen interactions.
Minov S.V.,Belgium Institute for Agricultural and Fisheries Research
Communications in agricultural and applied biological sciences | Year: 2012
The spray droplets generated by agricultural nozzles play an important role in the application accuracy and efficiency of plant protection products. The limitations of the non-imaging techniques and the recent improvements in digital image acquisition and processing increased the interest in using high speed imaging techniques in pesticide spray characterisation. The goal of this study was to develop an imaging technique to evaluate the characteristics of a single spray droplet using a piezoelectric single droplet generator and a high speed imaging technique. Tests were done with different camera settings, lenses, diffusers and light sources. The experiments have shown the necessity for having a good image acquisition and processing system. Image analysis results contributed in selecting the optimal set-up for measuring droplet size and velocity which consisted of a high speed camera with a 6 micros exposure time, a microscope lens at a working distance of 43 cm resulting in a field of view of 1.0 cm x 0.8 cm and a Xenon light source without diffuser used as a backlight. For measuring macro-spray characteristics as the droplet trajectory, the spray angle and the spray shape, a Macro Video Zoom lens at a working distance of 14.3 cm with a bigger field of view of 7.5 cm x 9.5 cm in combination with a halogen spotlight with a diffuser and the high speed camera can be used.