Blight-MOP: Development of a systems approach for the management of late blight (caused by Phytophthora infestans) in EU organic potato production

Blight-MOP Late blight (caused by Phytophthora infestans) is the most devastating fungal disease affecting organic (and conventional) potato production in the EU. It kills the foliage and usually results in losses of yield which can be very large when infection is severe and occurs early in the season. The disease may be transmitted to the tubers which become unmarketable and these can lead to complete deterioration of the stored crop if put into storage with healthy tubers. To a great extent, conventional production systems rely upon frequent applications of synthetic fungicides with different modes of action for late blight control, but this is seldom completely successful. However, in organic systems, the availability of chemical fungicides is currently restricted to those which are ‘considered to be traditional organic farming practices’: these include copper hydroxide, copper oxychloride (tribasic), copper sulphate and cuprous oxide that have a protectant action and are reasonably effective. Their use is restricted by national legislation and organic certifying authorities and pressure has been mounting to withdraw them not only because of possible adverse effects on wildlife, the environment and human health but also their incompatibility with organic production principles. This led to a proposed ban on the use of copper fungicides for control of late blight in organic farming in the EU from March 2002 which had potentially serious implications for the potato crop. The resultant losses of yield and hence income in the absence of copper-based fungicide sprays were expected to threaten the economic viability of both organic potato enterprises and/or whole organic farming businesses in many areas of the EU in the medium to long term until effective, alternative methods are developed. In the meantime, two major approaches were adopted. One was to set a limit to the amount of copperbased fungicides permitted for application: until 31 December 2005, the maximum application was restricted to 8kg of elemental copper/ha/year for annual crops, declining to 6kg/ha/year from 1 January 2006 (but this could be changed at any time in the light of developments in viable alternatives or should there be proposals for withdrawal under the EC Review programme for existing active substances). Another was to promote further research to identify and develop effective alternative late blight control methods and strategies without the undesirable effects associated with copper-based fungicides. The Blight-MOP project – ‘Development of a systems approach for late Blight (caused by Phytophthora infestans) Management in EU Organic Production systems’ was initiated in March 2001 to achieve this aim and maintain yield and quality and hence commercial viability of organic potato crops without the use of copper fungicides. Such an approach involves integrated use of (i) resistant varieties (ii) existing agronomic strategies (iii) alternative treatments that can replace synthetic and copper-based fungicides (iv) use of existing blight forecasting systems to optimise control treatments and to maximise synergistic interactions between (i), (ii), (iii) and (iv). The specific objectives were to: 1. Assess the socio-economic impact of late blight and ‘state-of-the-art’ blight management practices in EU organic potato production systems 2. Assess varietal performance in organic production systems in different EU regions and interactions with local blight populations 3. Develop within field diversification strategies to prevent/delay blight epidemics 4. Optimise agronomic strategies for the management of late blight 5. Develop alternative control treatments to copper-based fungicides that comply with organic farming standards 6. Evaluate novel application and formulation strategies for copper- free/alternative and copper-based late blight treatments 7. Integrate optimised resistance management, diversification, agronomic and alternative control treatment strategies into existing organic potato management systems. To pursue these objectives, experiments were conducted over 4 seasons from 2001 to 2004 under organic cropping system conditions in seven countries (Denmark, France, Germany, Netherlands, Norway, Switzerland and United Kingdom) spanning a wide range of aerial, soil, production and marketing environments. The rate and severity of the late blight epidemics in 2001, 2002 and 2004 gave a rigorous test of the different components of the integrated management system which gave broadly similar effects in the three years. In 2003, the very hot, dry summer (and August in particular) severely restricted the disease making it difficult to evaluate the efficacy of treatments in some regions, but in others where infection did occur the general trends were similar to those observed in other years

Educational achievement and ethnicity in compulsory schooling

This paper analyzes the evolution of the attainment gap between white British born and ethnic minority pupils throughout compulsory schooling, from the age of 5 to 16. At the start of school, pupils from most ethnic groups substantially lag behind White British pupils, but these gaps decline for all groups throughout primary and secondary school. Language is the single most important factor why most ethnic minority pupils improve relative to White British pupils. Although poverty explains part of the differences in levels, it cannot explain why ethnic minority pupils gain relative to or even overtake White British pupils. All ethnic minority groups initially attend worse performing schools than White British pupils. However, more than 20 percent of the subsequent relative improvement can be attributed to ethnic minority pupils moving up to better schools relative to White British pupils. Finally, our results suggest the possibility that the relative improvement of ethnic minority pupils may be related to teacher incentives to concentrate attention on particular pupils, caused by the publication of school league tables at the end of secondary school

Monitoring environmental cleanliness on two surgical wards

Ten hand-touch sites were screened weekly on two surgical wards over two consecutive six-month periods. The results were analysed using hygiene standards, which specify 1) an aerobic colony count (ACC) >2.5cfu/cm2, and 2) presence of coagulase-positive staphylococci, as hygiene failures. Sites most often failing the standards were beds and hoist (64%: 33 of 52 weeks), bedside lockers (62%: 32 of 52) and overbed tables (44%: 23 of 52). Methicillin-susceptible/resistant Staphylococcus aureus (MSSA/MRSA) were more often recovered from lockers, overbed tables and beds. Recovery of MSSA/MRSA at any site was significantly associated with an ACC>2.5cfu/cm2 from that site (p=0.001; OR: 3.35 (95% CI 1.79, 6.28)). In addition, total ACC's>2.5cfu/cm2 each week were significantly associated with weekly bed occupancies >95% (p=0.0004; OR: 2.94 (95% CI 1.44, 6.02)). Higher microbial growth levels from hand-touch sites reflect weekly bed occupancies and indicate a risk for both resistant and susceptible S.aureus. These organisms are more likely to be recovered from near-patient sites on the ward

Ex Situ Conservation Of Holstein-Friesian Cattle - Comparing The Dutch, French And USA Germplasm Collections

The establishment of gene banks using cryopreservation to secure the genetic diversity of farm breeds have been widely assessed. France, the Netherlands and the USA were among the first countries to organize national cryobanks and these banks are now 10 to 20 years old. All three countries have started Holstein-Friesian (HF) collections to conserve as much genetic diversity as possible for this globally important breed. In order better understand the diversity captured in these collections, the genetic variability of HF collections within and between countries was assessed, and genetic variability of germplasm collections were compared with active bulls in each country. The overall aim of the project was to determine the breed’s security and to guide future collection activities

Perturbative QCD and factorization of coherent pion photoproduction on the deuteron

We analyze the predictions of perturbative QCD for pion photoproduction on the deuteron, gamma D -> pi^0 D, at large momentum transfer using the reduced amplitude formalism. The cluster decomposition of the deuteron wave function at small binding only allows the nuclear coherent process to proceed if each nucleon absorbs an equal fraction of the overall momentum transfer. Furthermore, each nucleon must scatter while remaining close to its mass shell. Thus the nuclear photoproduction amplitude, M_{gamma D -> pi^0 D}(u,t), factorizes as a product of three factors: (1) the nucleon photoproduction amplitude, M_{gamma N_1 -> pi^0 N_1}(u/4,t/4), at half of the overall momentum transfer, (2) a nucleon form factor, F_{N_2}(t/4), at half the overall momentum transfer, and (3) the reduced deuteron form factor, f_d(t), which according to perturbative QCD, has the same monopole falloff as a meson form factor. A comparison with the recent JLAB data for gamma D -> pi^0 D of Meekins et al. [Phys. Rev. C 60, 052201 (1999)] and the available gamma p -> pi^0 p data shows good agreement between the perturbative QCD prediction and experiment over a large range of momentum transfers and center of mass angles. The reduced amplitude prediction is consistent with the constituent counting rule, p^11_T M_{gamma D -> pi^0 D} -> F(theta_cm), at large momentum transfer. This is found to be consistent with measurements for photon lab energies E_gamma > 3 GeV at theta_cm=90 degrees and \elab > 10 GeV at 136 degrees.Comment: RevTeX 3.1, 17 pages, 6 figures; v2: incorporates minor changes as version accepted by Phys Rev

Family visits to libraries and bookshops: observations and implications for digital libraries

This paper explores how families select books for leisure reading. We recruited 17 families (adults and children) for this study, and spent time with each in both bookshops and public libraries. Our research aims to add to understanding of how families interact with books and bookshelves in these places, and how digital libraries might best support the shared needs of these inter-generational users. Much of our understanding of how an eBook should look and feel comes from generalizations about books and assumptions about the needs of those individuals who read them. We explore how children and adults search and browse for books together, with specific focus on the type of information seeking tasks that families undertake and on the families’ shared search and browsing strategies. We further explore the implications of this study for the development of digital libraries for children and families