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Abstract:1. Pollination is an important ecosystem service as many agricultural crops such as fruit trees are pollinated by insects. Agricultural intensification, however, is one of the main drivers resulting in a serious decline of pollinator populations worldwide. 2. In this study pollinator communities were examined in twelve apple orchards surrounded by either homogeneous or heterogeneous landscape in Hungary. Pollinators (honey bees, wild bees, hoverflies) were surveyed in the flowering period of apple trees. Landscape heterogeneity was characterized in circles of 300, 500 and 1000 m radius around each orchard using Shannon's diversity and Shannon's evenness indices. 3. We found that pollination success of apple was significantly related to the species richness of wild bees, regardless the dominance of honey bees. 4. Diversity of the surrounding landscape matrix had a marginal positive effect on the species richness of hoverflies at 300m, positive effect on the species richness of wild bees at 500m radius circle, while evenness of the surrounding landscape enhanced the abundance of wild bees at 500m radius circle. Flower resources in the groundcover within the orchards supported honey bees. 5. Therefore maintenance of semi-natural habitats within 500m around apple orchards is highly recommended to enhance wild pollinator communities and apple production. Apple is one of the most important insect pollinated crops in the European Union, accounting 51 for 16% of the EU's total economic gains attributed to insect (particularly bee) pollination 52 (Leonhardt et al., 2013). Most apple varieties are cross-pollinated and insect pollination not 53 only affects the quantity of apple production, but can also have marked impacts on the quality 54 of the fruits, influencing size, shape and their market price (Garratt et al., 2014a). The most 55 common insect pollinator of apple is the honey bee (Apis mellifera); however, it is not the bees (Bosch & Blas, 1994). Hoverflies (Syrphidae) have also been observed with pollen loads 63 containing a high proportion of compatible fruit pollen (Kendall, 1973). Agricultural and Forest Entomology 64In the temperate zone, pollinator insects are under threat from a number of limiting 65 factors, such as climate change (Rader et al., 2013), human disturbance (Goulson et al., 66 2008), agricultural intensification (Kearns et al., 1998; Steffan-Dewenter et al., 2005; 67 Fitzpatrick et al., 2006; Memmott et al., 2007), and landscape fragmentation (Aizen & 68 Feisinger, 2003; Diekötter & Crist, 2013), which leads to less effective pollination and 69 reduces agricultural production (Floyd, 1992; Garibaldi et al., 2011a Garibaldi et al., , 2013 (Kremen et al., 2002; Brittain et al., 2013). Maintaining diverse communities, 94Apple is the most important fruit tree in Hungary, as it provides 60 % of the total 95Hungarian fruit production, and currently amounts to 400-600 thousand tons annually on We constructed generalized linear mixed models (GLMM) for each response variab...

We investigated the effects of nutritional limitation, humoral immune activation, and their interaction on postnuptial molting of aviary-kept house sparrows (Passer domesticus (L., 1758)). In a 2 Â 2 experimental design, we measured the progress of molting and the quality of feathers produced during molting by house sparrows exposed to different diet qualities (high and low) and humoral immune activation with sheep red blood cells (SRBC). Food quality, but not the activation of humoral immunity, affected significantly the body mass and the process of molting. Sparrows feeding on low-quality food had decreased body mass and longer molts than the high-quality group. Low-quality food, but not the activation of humoral immunity, reduced significantly the length and mass (i.e., the quality) of primaries grown during molting. Birds responded significantly to injection with SRBC compared with the control group, but the immune response was similar between nutritional groups. The absence of a negative effect of humoral immunity on molting in house sparrows might be related to the low energy and nutritional requirements of mounting and maintaining a humoral immune response.Résumé : Nous étudions les effets des restrictions alimentaires, de l'activation immunitaire humorale et de leur interaction sur la mue post-nuptiale chez des moineaux domestiques (Passer domesticus (L., 1758)) gardés en volière. Dans un plan d'expérience 2 Â 2, nous avons mesuré le progrès de la mue et la qualité des plumes produites par des moineaux exposés à des régimes alimentaires de qualité variable (haute et faible) et à une activation immunitaire humorale à l'aide d'érythro-cytes de mouton (SRBC). La qualité de la nourriture, mais non l'activation immunitaire humorale, affecte significativement la masse corporelle et le processus de mue. Les moineaux nourris d'un régime de faible qualité ont une masse corporelle réduite et une mue prolongée par rapport aux moineaux bien nourris. La faible qualité de l'alimentation, mais non l'activation de l'immunité humorale, réduit significativement la longueur et la masse (c'est-à-dire la qualité) des pennes primaires qui poussent pendant la mue. Les oiseaux réagissent significativement à l'injection de SRBC par comparaison au groupe témoin, mais la réponse immunitaire est semblable dans les deux groupes alimentaires. L'absence d'effet négatif de l'immunité humorale sur la mue des moineaux domestiques s'explique peut-être par les exigences énergétiques et alimentaires basses requises pour l'établissement et le maintien d'une réponse immunitaire humorale.[Traduit par la Rédaction]