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Róbert Gallé Péter Császár Tímea Makra Nikolett Gallé-Szpisjak Zsuzsanna Ladányi Attila Torma Kapilkumar Ingle Péter Szilassi 《Landscape Ecology》2018,33(8):1435-1446
Context
Intensive agricultural management practices and landscape homogenisation are the main drivers of biodiversity loss in agricultural landscapes. Agricultural fields are regularly disturbed and provide unstable habitats due to crop management regimes. This may lead to movement of arthropods into neighbouring non-arable habitats, as natural and semi-natural habitats provide suitable overwintering sites.Objectives
Here we assessed the effect of landscape composition and configuration on the overwintering spider and carabid fauna of grassy field margins and hedgerows.Methods
We sampled ground-dwelling arthropods at field edges of different types (grassy field margin and hedgerows), landscape composition (diverse and simple) and configuration (mosaic and large-scale agricultural landscapes).Results
We detected larger spiders in hedgerows than in grassy field margins and in complex landscapes rather than in simple landscapes. We found a significant effect of interaction between landscape composition and edge type on ballooning propensity of spiders. Agrobiont carabids were more abundant in field edges of compositionally simple and large-scale agricultural landscapes. Furthermore, we showed an effect of interaction between landscape composition and edge type on agrobiont spiders. We collected larger carabids in grassy field margins than in hedgerows and carabids were smaller in simple landscapes than in diverse landscapes. The spider community was affected by edge type, and landscape composition had a significant effect on the carabid community.Conclusions
Small-scale agricultural landscapes may have higher overall densities of ground-dwelling spiders and carabids than large scale landscapes due to the relatively high edge density and the higher quantity of available overwintering sites.154.
155.
Szabó-Hevér Ágnes Lehoczki-Krsjak Szabolcs Varga Mónika Purnhauser László Pauk János Lantos Csaba Mesterházy Ákos 《Euphytica》2014,200(1):9-26
The genetic background of Fusarium head blight (FHB) resistance in the moderately resistant wheat variety Frontana was investigated in the GK Mini Manó/Frontana DH population (n = 168). The plant material was evaluated across seven epidemic environments for FHB, Fusarium-damaged kernel (FDK) and deoxynivalenol (DON) contents caused by two Fusarium species (F. culmorum and F. graminearum). The effects of phenotypic traits such as plant height and heading date were also considered in the experiments. In the population, 527 polymorph markers (DArT, SSR) within a distance of 1,381 cM distance were mapped. The quantitative trait locus/loci (QTL) on chromosomes 4A and 4B demonstrated a significant linkage only with FHB, while QTL on chromosomes 3A, 4B, 7A and 7B were linked to DON accumulation alone. Regions determining all the investigated Fusarium resistance traits were identified on chromosomes 1B, 2D, 3B, 5A, 5B and 6B. The markers in these regions are of the greatest significance from the aspect of resistance breeding. Our results indicate that the genetic background of resistance against FHB, FDK and DON accumulation can differ, and all these traits should be taken under consideration during resistance tests. Moreover, this is the first report on the mapping of Frontana-derived QTL that influence DON accumulation, which is important since the level of DON contamination determines the actions of the food and feed industries. Selection should therefore also focus on this trait by using molecular markers linked to DON content. 相似文献
156.
Using data for U.S. metropolitan statistical areas, an earlier study of aggregate local geographic research spillovers generated by universities (Anselin et al.1997) was extended to a sectorally disaggregated level. These findings suggest the existence of significant sectoral variation with respect to local university effects on innovation. Apparent differences were found across sectors with respect to the “mix” of applied local knowledge inputs in general, and the extent to which university research plays a role in innovation in particular. The main conclusion is that local university spillovers seem to be specific to certain industries, such that at the two‐digit SIC level, no university spillover effects are at work in the Drugs and Chemicals (SIC28) and in the Machinery (SIC35) sectors. On the contrary, very strong and significant university research spillovers are evidenced in the Electronics (SIC36) and the Instruments (SIC38) industries. These spillovers extend beyond the boundary of the MSA within a 75‐mile range from the central city. 相似文献
157.
Gyula Pinke Kálmán Tóth Attila J. Kovács Gábor Milics Zoltán Varga Katinka Blazsek 《国际虫害防治杂志》2014,60(3):187-195
Two field experiments were carried out a year apart on the alkaloid poppy (Papaver somniferum) in 2012 and 2013 in north-west Hungary, to assess the efficacy of mesotrione and tembotrione herbicides for post-emergence weed control. Our experiments tested (1) a single application of mesotrione at 144 g active ingredient (a.i.) ha–1, (2) two separate applications of mesotrione at 144 g a.i. ha–1, (3) a single application of tembotrione at 88 g a.i. ha–1, (4) two separate applications of mesotrione at 88 g a.i. ha–1, and (5) the combination of a single application of mesotrione at 144 g a.i. ha–1 followed by a single application of tembotrione at 88 g a.i. ha–1. Both non-treated and hand-weeded plots were used as controls. Among the most important weeds, Chenopodium album was most successfully controlled in the majority of the test treatments, but Fallopia convolvulus and Polygonum aviculare tolerated each herbicide application in 2012, likely due to the dry weather conditions. Because of the botanical similarity to the crop, none of the treatments proved to be significant against Papaver rhoeas. One dosage of tembotrione alone never reduced the dry weights of the target weed species or weed numbers significantly. The cuticular wax layer of the opium poppy can provide a natural defence against these herbicides, but some temporary phytotoxic yellowish discoloration occurred after tembotrione treatments. Our results show that mesotrione in combination with tembotrione is the most effective treatment and should be employed in poppy cultivation. 相似文献
158.
159.
M. Elliott G. Sumampong A. Varga S. F. Shamoun D. James S. Masri S. C. Brière N. J. Grünwald 《Forest Pathology》2009,39(4):266-278
Phytophthora ramorum, the cause of sudden oak death and ramorum blight, has three major clonal lineages and two mating types. Molecular tests currently available for detecting P. ramorum do not distinguish between clonal lineages and mating type is determined by cultural methods on a limited number of samples. In some molecular diagnostic tests, cross‐reaction with other closely related species such as P. hibernalis, P. foliorum or P. lateralis can occur. Regions in the mitochondrial gene Cox1 are different among P. ramorum lineages and mitochondrial genotyping of the North American and European populations seems to be sufficient to differentiate between mating types, because the EU1 lineage is mostly A1 and both NA1 and NA2 lineages are A2. In our study, we were able to identify P. ramorum isolates according to lineage using polymerase chain reaction‐restriction fragment‐length polymorphism (PCR‐RFLP) of the Cox1 gene, first by using ApoI to separate P. ramorum from other species and EU1 from North American populations, and then AvaI to distinguish between NA1 and NA2 genotypes. However, P. foliorum had the same restriction profile as P. ramorum NA1 isolates. 相似文献
160.
Faustman DL Tran SD Kodama S Lodde BM Szalayova I Key S Toth ZE Mezey E 《Science (New York, N.Y.)》2006,314(5803):1243; author reply 1243
Chong et al., Nishio et al., and Suri et al. (Reports, 24 March 2006, pp. 1774, 1775, and 1778) confirmed that treating nonobese diabetic (NOD) mice with an immune adjuvant and semisyngenic spleen cells can reverse the disease but found that spleen cells did not contribute to the observed recovery of pancreatic islets. We show that islet regeneration predominately originates from endogenous cells but that introduced spleen cells can also contribute to islet recovery. 相似文献