Comparative repellent activity of single,binary and ternary combinations of plant essential oils and their major components against Sitophilus oryzae L. (Coleoptera: Curculionidae)

Journal of Plant Diseases and Protection - In the present study, repellent activity of three plant essential oils (EOs) [anise (Pimpinella anisum L.), eucalyptus (Eucalyptus camaldulensis...     

Nachhaltgerechte Technikgestaltung in der Forstwirtschaft — ein Modellansatz

Zusammenfassung Forsttechnische Verfahren sind selbst nicht nachhaltig, beeinflussen aber die nachhaltige Forstbewirtschaftung in vielf?ltiger Weise: Sie k?nnen einerseits direkten Einflu? auf Umwelt und Gesellschaft ausüben, andererseits indirekt die Leistungen der Forstwirtschaft oder die Wirkungen des Waldes st?ren oder f?rdern. Um sie umfassend zu beurteilen, müssen neben den klassischen Kriterien “Funktionsf?higkeit” und “Effizienz” auch die “?koeffizienz” und die ?kologische, soziale und die ergonomische “Vertr?glichkeit” beachtet werden. Bei der daran anschlie?enden Entscheidung für ein Verfahrenoder die Nullvariante - verlangen verschiedene Hürden wie Skalenniveaus, Werte, Restriktionen, Zielkonzept des Betriebes und Unsicherheiten bezüglich Wirkungen der Verfahren oder künftiger Entwicklungen nach einem umfassenden Modell, für das ein Vorschlag unterbreitet wird. Schlie?lich wird postuliert, da? sich unter anderem an der im Wald eingesetzten Technik entscheiden wird, ob künftig den Forstleuten noch die Kompetenz zugestanden wird, den Wald zu bewirtschaften. Summary Technical processes in forestry are not sustainable as such, but affect sustainable forest management in many ways. They may have a direct effect on the environment and society or they may indirectly either interfere with or promote benefits from forestry and the effects of the forest. For a comprehensive assessment of these effects “eco-efficiency” and ecological, social and ergonomie “compatibility” have to be taken into consideration apart from classical criteria such as “functionality” and “efficiency”. When deciding in favour of a process - or the control variate - various obstacles such as scale levels, values, restrictions, operational objectives and uncertainties regarding the effects of processes or future developments call for a comprehensive model, as proposed in this study. Finally, the postulate is advanced that it will also depend on the technics used in the forest whether forestry experts will be considered sufficiently competent to continue to manage our forests in the future.     

Response of beech and oaks to wounds made at different times of the year

Tree care, especially pruning, is still mostly done in the dormant time. Such treatments expose live inner bark, the vascular cambium, and functioning outer sapwood to harsh external influences followed often by infection of pathogens. Investigations about response reactions of beech and oak to wounding made in different times of the year showed that wound closure was significantly slower for December and February wounds than in April and October. The length of discoloured sapwood was in October and December wounds greater than in February and April. Sapwood reaction expressed by the soluble phenol concentration index indicated however no significant differences among wounding dates. Overall, woundings in the vegetation period will be more effectively compartmentalized than in the dormant season. Consequently, tree care like pruning with many woundings should not be done in the winter period.Presented at the 6th ISA European Conference, 9.-12. June 2004, Maastricht, The Netherlands     

Larvicidal activity of a botanical natural product, AkseBio2, against Culex pipiens

A botanical natural product, AkseBio2, was evaluated for its larvicidal effect against Culex pipiens under laboratory conditions. The product exhibited strong larvicidal activity and caused >90% mortalities in both the young (first-second) and the older (third-fourth) larval stages of the species at 24 h at the doses of 25 and 50 ppm. However, it was determined that the young larval stages were more susceptible to the product in comparison with the older larval stages. The results suggest that the product is promising as a larvicide against C. pipiens and could be useful in the search of new larvicidal natural compounds.     

Applying IUCN criteria to invertebrates: How red is the Red List of European butterflies?

The IUCN is the leading authority on assessing species’ extinction risks worldwide and introduced the use of quantitative criteria for the compilation of Red Lists of threatened species. Recently, we assessed the threat status of the 483 European butterfly species, using semi-quantitative data on changes in distribution and in population sizes provided by national butterfly experts. We corrected distribution trends for the observation that coarse-scale grid cells underestimate actual population trends by 35%. To account for uncertainty, we included a 5% error margin on the distribution and population trends provided. The new Red List of European butterflies determined one species as Regionally Extinct, 37 species as threatened (Critically Endangered, Endangered or Vulnerable) and a further 44 as Near Threatened. The use of semi-quantitative data on distribution and population trends permitted us to use IUCN criteria to compile a scientifically underpinned Red List of butterflies in Europe. However, a comparison of detailed monitoring data for some grassland species showed that coarse-scale grid cell data and population trends strongly underestimate extinction risks, and the list should be taken as a conservative estimate of threat. Finally, combining the new Red List status with the data provided by the national butterfly experts, allowed us to determine simple criteria to delineate conservation priorities for butterflies in Europe, so called SPecies of European conservation Concern (SPEC’s). Using European butterflies, our approach illustrated how Red Listing can be performed when data are incomplete for some IUCN criteria or vary strongly among countries.     

Will climate change reduce the efficacy of protected areas for amphibian conservation in Italy?

Amphibians are an important and imperiled component of biodiversity. In this study we analyze the efficacy of Italian reserve network for protecting multiple amphibian species in a climate change scenario, considering both nationally designated areas and Natura 2000 sites. Our approach is based on ensemble niche modeling estimate of potential range shift under two carbon emission scenarios (A1FI and B1) and two dispersal assumptions. The predicted distributions were used to perform gap and irreplaceability analyses. Our findings show that the current Italian reserve network incompletely represents current amphibian diversity and its geographic pattern. The combination of the nationally designated protected areas and the Natura 2000 sites improves current representation of amphibians, but conservation targets based on geographic range extent are achieved for only 40% of species. Under the future scenarios, Natura 2000 sites become a crucial component of the protected areas system. Nonetheless, we predict that climate change decreases for many species the amount of suitable range falling into reserves, regardless of our assumptions about dispersal. We identify some currently unprotected areas that have high irreplaceability scores for species conservation and that maintain their importance under all the future scenarios we considered. We recommend designation of new reserves in these areas to help guarantee long-term amphibian conservation.     

Assessment and quantification of post-weaning multi-systemic wasting syndrome severity at farm level

Post-weaning multi-systemic wasting syndrome (PMWS) causes major economic losses for the English pig industry and severity of clinical signs and economic impact vary considerably between affected farms. We present here a novel approach to quantify severity of PMWS based on morbidity and mortality data and presence of porcine circovirus type 2 (PCV2). In 2008-2009, 147 pig farms across England, non-vaccinating for PCV2, were enrolled in a cross-sectional study. Factor analysis was used to generate variables representing biologically meaningful aspects of variation among qualitative and quantitative morbidity variables. Together with other known variables linked to PMWS, the resulting factors were included in a principal component analysis (PCA) to derive an algorithm for PMWS severity. Factor analysis resulted in two factors: Morbidity Factor 1 (MF1) representing mainly weaner and grower morbidity, and Morbidity Factor 2 (MF2) which mainly reflects variation in finisher morbidity. This indicates that farms either had high morbidity mainly in weaners/growers or mainly in finishers. Subsequent PCA resulted in the extraction of one component representing variation in MF1, post-weaning mortality and percentage of PCV2 PCR positive animals. Component scores were normalised to a value range from 0 to 10 and farms classified into: non or slightly affected farms with a score <4, moderately affected farms with scores 4-6.5 and highly affected farms with a score >6.5. The identified farm level PMWS severities will be used to identify risk factors related to these, to assess the efficacy of PCV2 vaccination and investigating the economic impact of potential control measures.     

Predicting fadeout versus persistence of paratuberculosis in a dairy cattle herd for management and control purposes: a modelling study

ABSTRACT: Epidemiological models enable to better understand the dynamics of infectious diseases and to assess ex-ante control strategies. For Mycobacterium avium subsp. paratuberculosis (Map), possible transmission routes have been described, but Map spread in a herd and the relative importance of the routes are currently insufficiently understood to prioritize control measures. We aim to predict early after Map introduction in a dairy cattle herd whether infection is likely to fade out or persist, when no control measures are implemented, using a modelling approach. Both vertical transmission and horizontal transmission via the ingestion of colostrum, milk, or faeces present in the contaminated environment were modelled. Calf-to-calf indirect transmission was possible. Six health states were represented: susceptible, transiently infectious, latently infected, subclinically infected, clinically affected, and resistant. The model was partially validated by comparing the simulated prevalence with field data. Housing facilities and contacts between animals were specifically considered for calves and heifers. After the introduction of one infected animal in a naive herd, fadeout occurred in 66% of the runs. When Map persisted, the prevalence of infected animals increased to 88% in 25 years. The two main transmission routes were via the farm's environment and in utero transmission. Calf-to-calf transmission was minor. Fadeout versus Map persistence could be differentiated with the number of clinically affected animals, which was rarely above one when fadeout occurred. Therefore, early detection of affected animals is crucial in preventing Map persistence in dairy herds.