Vegetation development in sown field margins and on adjacent ditch banks

The creation of temporal and newly sown field margins for 6 years is a common agri-environment scheme (AES) in the Netherlands. Conservation profits resulting from AES vary over different areas and need further studying. We examined plant species richness in such field margins and adjacent ditch banks in the province of Zeeland, where these linear elements do not experience plant biomass removal after mowing as management strategy. First, during 2 years, we inventoried field margins sown with a wildflower mixture and related the species composition and richness to the age of the margins. In a second assessment, we studied plant species richness on ditch banks protected from arable fields by these margins. Major clusters in a principal component analysis (PCA) on species composition in the field margins showed a succession from sown and ruderal annual species (year 1), to sown perennial species (year 2) and ending with a dominance by tussock forming grass species and Urtica dioica (year 5–6). Total plant species richness decreased with increasing age of the margins, and this was caused by the combination of a decline in sown species and a stable number of not-sown species. The presence of field margins during several years did not result in an increase in plant species richness on adjacent ditch banks. In both the field margins and on the ditch banks, mowing management is not followed by the removal of the cuttings. For plant conservation, the results of these field margins are disappointing, probably due to the lack of a proper management. Therefore, we recommend implementing a hay-making and opening management, to increase plant richness and to reduce noxious weeds in the margins and on the ditch bank

Political Performance, Leadership, and Regional Integration in Europe: An Examination of the French and German Roles

Prior research on a regional leader’s role in the deepening of regional integration assumes that economic power translates directly into political capabilities. Relative political capacity among states is central to the creation and deepening of regional integration since it is this capacity that smoothes out the transition from a closed to an open economy. Should a state have low levels of this capacity but desire openness, it will partner with regional leaders given the leaders’ higher relative political capacity. However, the leaders’ subsidy of a partner’s capacity comes at a price. The leaders would trade political capacity for forming a regional bloc along its preferences. A partner will join with a regional leader so long as it is satisfied with the leaders’ preferences. By doing so, it reduces the cost of the subsidy. Our analysis of European integration indicates that French and German relative political capacities are an important factor in the continent’s unifying efforts by conditioning institutional homogeneity and capital stocks mobility, both of which are critical for political and economic union. However, the German effect contrasts with the French effect in that we discover greater German effectiveness in mitigating potential barriers to integration

Wegberm biedt hulp tegen bestuivingscrisis

De achteruitgang van bloemzoekende insecten is een bedrieging voor een scala aan ecologische processen en diensten die deze dieren verzorgen. Wegbermen zijn vaak rijk aan bloeiende kruiden en kunnen daardoor van groot belang zijn voor deze dieren. Maar hoe kunnen deze bermen het beste beheerd worden? Wageningen Universiteit deed een experiment in een grazige berm, waarbij bloembezoek bekeken werd in relatie to vijf maairegime

Identification and mapping of the novel apple scab resistance gene Vd3

Apple scab, caused by the fungal pathogen Venturia inaequalis, is one of the most devastating diseases for the apple growing in temperate zones with humid springs and summers. Breeding programs around the world have been able to identify several sources of resistance, the Vf from Malus floribunda 821 being the most frequently used. The appearance of two new races of V. inaequalis (races 6 and 7) in several European countries that are able to overcome the resistance of the Vf gene put in evidence the necessity of the combination of different resistance genes in the same genotype (pyramiding). Here, we report the identification and mapping of a new apple scab resistance gene (Vd3) from the resistant selection “1980-015-25” of the apple breeding program at Plant Research International, The Netherlands. This selection contains also the Vf gene and the novel V25 gene for apple scab resistance. We mapped Vd3 on linkage group 1, 1 cM to the south of Vf in repulsion phase to it. Based on pedigree analysis and resistance tests, it could be deduced that 1980-015-25 had inherited Vd3 from the founder “D3.” This gene provides resistance to the highly virulent EU-NL-24 strain of race 7 of V. inaequalis capable of overcoming the resistance from Vf and Vg

Omzien in verwondering

Biologische, fysische en klinische aspecten van de behandeling van kanker met ioniserende stralin

Impact of a road on the movements of two ground beetle species (Coleoptera: Carabidae)

We studied the effects of a road on the walking directions of the carabid species Poecilus versicolor and Agonum sexpunctatum. Using mark and recapture experiments and window trapswe determined the number of road crossings and the deviation in walking directions caused by the road. We found two effects of the road on the walking behaviour: (1) the road is a barrier to both species, but whereas P. versicolor was reluctant to cross the road and had a significant movement away from the road, we recorded no road crossings by A. sexpunctatum; and (2) A. sexpunctatum showed a marked tendency to walk along the roadside verge, particularly in the ditch. Of these two species, only one individual of A. sexpunctatum was caught flying close to the road, indicating that itmight cross the road by flying. Counts of dead carabid specimens on two 100 m long transects along the road carried out for nine weeks recorded several individuals of P. versicolor. We conclude with suggestions on how to implement the results of this study in nature conservation practices

Europees Loopkevercongres jubileert in Nederland

De 1e Europese loopkeverovereenkomst werd in 1969 in Wijster georganiseerd. 40 jaar erna wordt in 2009 het jubileumcongres weer in Nederland georganiseerd. Deze bijdrage belicht de bijzondere relatie tussen Nederland en de European Carabidologist Meeting (ECM

Laat de ‘echte man’ opstaan : een systematisch-theologisch onderzoek naar de rol en betekenis van masculiniteit binnen de 4e Musketier en het jeugdwerk van de Protestantse Kerk

Masterthesis Gemeentepredikant, Systematische theologi