Weed control in glyphosate tolerant sugar beet.

End of Project ReportBetween 1997 and 1999 weed control trials were carried out with sugar beet tolerant to glyphosate. Glyphosate was applied at a total dose of 1620.0, 2160.0, 3240.0 and 4320.0 g a.i. ha-1 in two and three applications. These were compared with a standard and double standard three spray sugar beet herbicide programme. In all seasons application of the lowest dose of glyphosate, 1620.0 g a.i. ha-1 gave marginally better control of weeds than the standard herbicide programme. Herbicide timing was more flexible with glyphosate and only two weeds, Polygonum convolvulus and Lamium purpureum required more than one application to kill all the weeds. In most cases no significant difference in weed control was observed between the glyphosate treatments after the second and third applications but the three spray programmes were marginally better than the two spray in 1997 and 1998. In 1997 the sugar beet strain was not totally tolerant to glyphosate and a reduction in plant numbers was recorded after the initial glyphosate application. The strain used in subsequent years was fully tolerant and no plant loss occurred even at the highest glyphosate dose. At harvest most of the root yields in the glyphosate treatments were significantly higher than the yields from the standard herbicide comparison treatments. Crop vigour was not affected by any of the treatments in 1997 but in 1998 and 1999 the two standard herbicides reduced crop vigour by 10 and 20 per cent respectively

Reduced Herbicide Inputs in Cereals

End of Project ReportThe objective of this project was to examine if herbicides used in cereals at rates lower than recommended by the manufacturer (reduced rates) would give acceptable weed control resulting in lower crop production costs. Field trials with a number of herbicides at full and reduced rates were carried out in winter barley, winter wheat and spring barley in 1994-1996. Herbicides used at recommended rates gave the highest and most consistent levels of weed control. Herbicides used at 50% of the recommended rates gave slightly lower levels of weed control than the recommended rates but did not result in lower yields. While rates lower than 50% gave about 70% control of weeds, grain yield was reduced in some trials. Reduced rates gave higher weed control in barley than in wheat. The level of weed control was influenced by weed species and the growth stages of the weeds at the time of herbicide spraying. Thus selection of herbicides and their rates of application should be field specific. The findings show that it is possible to reduce the amount of herbicides used in cereals with considerable cost savings and reduced risk of herbicide residues in grain, soil and water.Cereals Levy Farmer FundsEuropean Union Structural Funds (EAGGF

Low herbicide use in sugar beet

End of Project ReportTeagasc acknowledges with gratitude the support of Sugar Beet Growers, Irish Sugar plc and European Union Structural Funds (EAGGF) in the financing of this research project.Trials with the new sulphonylurea herbicide, Debut, controlled a wide spectrum of weeds common to Irish sugar beet. These included problem weeds such as cleavers, charlock, mayweed and fools parsley. Best results were obtained when the new product was applied with half the normal recommended dose of the standard contact and residual sugar beet herbicides. Thus the overall active ingredient applied to crop and soil was reduced with no loss in weed control efficacy and crop safety. A three year study comparing two and three spray weed control programmes on triploid sugar beet varieties and the more erect growing diploid beet varieties was also undertaken. Results indicated no difference in weed control efficacy or yield response between the two variety types although similar work in the Netherlands indicated otherwise. A third investigation into the use of two spray weed control programmes for sugar beet indicated that when applied to sugar beet sown in April commercially acceptable weed control was feasible as long as weed pressure was not excessive and sprays were applied at the correct stage of weed growth.European UnionIrish Sugar pl

Herbicide Efficacy Evaluation

End of Project ReportThe objective of this series of trials was to determine if recently introduced herbicide formulations give better weed control in cereals and grassland than those presently in use. Effect on crop yield and quality was also examined where appropriate. In 1995, field trials were carried out with a new diflufenican/flurtamone formulation, Bacara, in winter wheat and barley. In both cases, the results showed that this new formulation gave commercially acceptable weed control of a wide range of annual weeds and grasses, when applied at doses between 260 and 350 g a.i. per hectare. None of the products tested had any adverse effects on crop yield or quality. Between 1996 and 1998 a number of new sulfonylurea herbicides, based on carfentrazone and flupyrsulfuron methyl (Lexus series), were tested at trial sites in Carlow and Clonmel. Most of the formulations gave weed control similar to Cougar, which was included in all these trials as standard comparison treatment, without affecting crop yield or quality. New herbicide trials for the control of broad and curled leaf dock (Rumex spp.) in pasture were carried out. Most of the herbicides investigated gave better overall control of both species than the standard dicamba/mecoprop based products. One of the sulfonylyurea-based herbicides controlled broad leaf dock only, and occasionally retarded grass development, but had no effect on clover. Fluroxypyr-based products gave long term control of both dock species without any effect on the grass, but eliminated clover present in the sward. In all trials some dock regrowth was evident one year after treatment

Management of severe aortic valve stenosis in the neonate

Aortic valve stenosis (AS) causing obstruction to the left ventricular outfl ow, and hence reduction of the cardiac output, remains a therapeutic challenge for paediatric cardiologists and cardiothoracic surgeons. Infants that present at birth may have very dysplastic valves with severe or critical AS and are typically the most diffi cult to treat. This article therefore focuses on the managementof severe AS in the neonate. This article also revises the embryology of the semi-lunar valves, as the morphology of the aortic valve often dictates the treatment pathway

The use of air induction nozzles for herbicide application to sugar beet.

End of Project ReportTrials were carried out over a three-year period in Oak Park to compare airinduction with conventional nozzles for weed control in sugar beet. Two makes of low-drift nozzle (Bubble Jet and DriftBETA) were compared with conventional fans. All nozzles were used at a pressure of 3 bar. Two sizes (015 and 03) of each type of nozzle were used, to allow volumes of 110 and 220 litres per hectare to be applied. These nozzles were used to apply two-spray programmes to sugar-beet crops. In four of the weed control trials, tank mixes of products with some residual action (Progress, Goltix, Venzar and Debut) were used. In the other two trials, a contact-only spray (Betanal E) was used. The aim was to see how the nozzles behaved with contact-only sprays as well as those with more complex modes of action. Spray drift was also measured with the size 03 nozzles. Spray drift reductions from 37% to 64% were measured when the air-induction nozzles were compared with conventional fans. In general, the tank mix programme gave better weed control than the contact-only treatments. Within programmes, differences between the application methods were significant in two trials. In both of these, the conventional nozzles gave the best results. Looking at the mean results of the tank-mix trials, two trends were suggested: higher water volumes gave slightly better weed control, and the effect of the coarser sprays was slight. With the contact-only sprays, the decline in performance with the coarser sprays was more emphatic, and the lower volumes appeared to give slightly better control. It is concluded that in calm conditions conventional fan or cone nozzles should continue to be used, but that air-induction nozzles are a valuable fall-back when it is necessary to spray in a moderate breeze. In these situations, and with the normal tank-mix programmes, small nozzle sizes applying very low volumes should be avoided. Makes of air-induction nozzle which give very coarse spray should also be avoided

Complete seismogram synthesis for transversely isotropic media

The response at the surface of a layered transversely isotropic medium due to a buried dislocation source can be expressed by using propagator matrices and discrete wavenumber summation. These operations produce complete seismograms for earthquake or explosion sources which include all body- and surface-vave phases for this specialized anisotropic structure. In order to test the numerical procedures, synthetic seismograms at near distances for an isotropic model are compared with those generated by other methods. The agreement is found to be satisfactory in all cases. Comparisons of synthetic seismograms for anisotropic models having a small degree of anisotropy with similar but isotropic models, show that significant differences in travel times, amplitudes and wave forms can be caused by the anisotropy.           ARK: https://n2t.net/ark:/88439/y066890 Permalink: https://geophysicsjournal.com/article/226 &nbsp

A study of cultivation and sowing systems for cereals.

End of Project ReportDue to the pressure on cereal margins growers are seeking ways of reducing their costs of production. Reduced cultivation may provide cheaper and faster crop establishment, but in the past has been subject to problems with (poor crop establishment) weeds and soil compaction. With modern cultivation and sowing technology and methodology it may be possible to overcome these difficulties. In addition reduced cultivation is considered to be more environmentally friendly and sustainable than the conventional plough-based system. With these considerations in mind it was decided to start an experiment in autumn 2000 to compare the conventional system (PL) with reduced cultivation (RC) for crop establishment, and to examine the effect of incorporating the straw into then soil or baling and removing it. The treatments were assessed on winter wheat, and winter and spring barley. The parameters assessed included – crop establishment, yield and quality effects on disease levels, invertebrate pests and beneficials (aphids, slugs, earthworms, beetles), and soil conditions. The work reported here was conducted on four trial sites at Oak Park, Carlow and Knockbeg, Co. Laois from 2000 to 2003. the objectives were to establish the efficacy of RC compared with PL and to its effects on the parameters outlined above. Plant establishment was lower after RC in most of the experiments. Winter wheat yields were good irrespective of the number of plants established and there were no significant differences between cultivation or straw disposal method. The relative yields of the PL and RC treatments in winter barley varied over the three years; in 2001 there was no difference, in 2002 PL yielded 1 t/ha more than RC, while in 2003 the PL area produced 2 t/ha extra. Spring barley yields were similar on the PL and RC treatments. Broadleaved weeds were not a problem on the PL or RC treatments but there were more annual grass weeds on the RC plots. This was particularly serious in the winter barley experiments where sterile brome (Bromus sterilis) had a big effect on yield by 2003. annual meadow grass (Poa annua) was a problem in both PL and RC areas if not controlled by timely herbicide application; this was particularly so on the headland areas in the spring barley field. Disease assessment on the winter wheat trail showed no significant differences in Take-all or Eyespot levels between cultivation or straw disposal methods, although Take-all levels tended to be lower on the RC plots. Soil strength as measured by cone penetrometer and shear vane was higher on the RC treatments. In the winter wheat there was no difference in slug numbers between any of the treatments. Leaf damage by slugs increased in RC relative to PL but not significantly, in 2003. No below ground slug damage was found. Earthworm numbers in the winter barley increased significantly on the RC treatment relative to the PL as the study progressed. Straw incorporation increased earthworm numbers on both PL and RC treatments. Allolobophora chlorotia was the most common species in 2004. In the winter wheat the RC and straw incorporation increased earthworm numbers. Cultivation method had a greater effect on ground beetle numbers than method of straw disposal. Large species (e.g. Pterostichies malanarius) were favoured by RC while smaller species (e.g. Bembidon species) were more numerous in the PL plots. Molecular studies on virus diseases, vectors and vector-predators are underway in progress. In the invertebrate pests and beneficials investigations the RC winter barley had 11% fewer aphids and 27% less BYDV than the PL. Incorporating straw reduced aphid numbers and virus incidence by 36% and 32% respectively; the comparable values for the PL + straw treatment were 15% and 15%. In the winter wheat there was less BYDV in the RC plots than the PL + less were the straw was incorporated than where the straw was removed. Aphid infestation of wheat ears was low in the three years of the experiment. The insecticide seed treatment imidacloprid significantly reduced aphid numbers and virus incidence in winter barley but was less effective than a single insecticide spray in controlling the disease. The seed treatment was more effective in controlling BYDV in RC than in the PL plots. Estimations of slug numbers in the winter barley showed that the dominant species was the grey field slug (Deroceras reticulatum). Slug numbers increased significantly on all treatments between 2001 and 2004. In November 2004, slugs were significantly more numerous in the RC treatments than in the PL areas. Leaf damage was proportional to slug populations, but the slugs did not damage the barely seed or reduce plant populations in continuous winter barley under RC. Root and stem diseases (Take-all and Eyespot) were not nay worse under RC than after PL. In fact there was a tendency towards lower disease levels on the RC areas and there was significantly less sharp eyespot on the RC treatment

Interactive Training System for Interventional Electrocardiology Procedures

International audienceRecent progress in cardiac catheterization and devices al-lowed to develop new therapies for severe cardiac diseases like arrhyth-mias and heart failure. The skills required for such interventions are still very challenging to learn, and typically acquired over several years. Vir-tual reality simulators can reduce this burden by allowing to practice such procedures without consequences on patients. In this paper, we propose the first training system dedicated to cardiac electrophysiology, includ-ing pacing and ablation procedures. Our framework involves an efficient GPU-based electrophysiological model. Thanks to an innovative mul-tithreading approach, we reach high computational performances that allow to account for user interactions in real-time. Based on a scenario of cardiac arrhythmia, we demonstrate the ability of the user-guided simulator to navigate inside vessels and cardiac cavities with a catheter and to reproduce an ablation procedure involving: extra-cellular poten-tial measurements, endocardial surface reconstruction, electrophysiology mapping, radio-frequency (RF) ablation, as well as electrical stimulation. This works is a step towards computerized medical learning curriculum

Phagosomal acidification Is required to kill Streptococcus pneumoniae in a Zebrafish model

Streptococcus pneumoniae (the pneumococcus) is a major human pathogen causing invasive disease, including community-acquired bacteraemia, and remains a leading cause of global mortality. Understanding the role of phagocytes in killing bacteria is still limited, especially in vivo. In this study, we established a zebrafish model to study the interaction between intravenously administered pneumococci and professional phagocytes such as macrophages and neutrophils, to unravel bacterial killing mechanisms employed by these immune cells. Our model confirmed the key role of polysaccharide capsule in promoting pneumococcal virulence through inhibition of phagocytosis. Conversely, we show pneumococci lacking a capsule are rapidly internalised by macrophages. Low doses of encapsulated S. pneumoniae cause near 100% mortality within 48 hours postinfection (hpi), while 50 times higher doses of unencapsulated pneumococci are easily cleared. Time course analysis of in vivo bacterial numbers reveals that while encapsulated pneumococcus proliferates to levels exceeding 105 CFU at the time of host death, unencapsulated bacteria are unable to grow and are cleared within 20 hpi. Using genetically induced macrophage depletion, we confirmed an essential role for macrophages in bacterial clearance. Additionally, we show that upon phagocytosis by macrophages, phagosomes undergo rapid acidification. Genetic and chemical inhibition of vacuolar ATPase (v-ATPase) prevents intracellular bacterial killing and induces host death indicating a key role of phagosomal acidification in immunity to invading pneumococci. We also show that our model can be used to study the efficacy of antimicrobials against pneumococci in vivo. Collectively, our data confirm that larval zebrafish can be used to dissect killing mechanisms during pneumococcal infection in vivo and highlight key roles for phagosomal acidification in macrophages for pathogen clearance