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1.
Primer sequence and polymorphism data are presented for 13 microsatellite loci isolated from the European corn borer moth, Ostrinia nubilalis, as part of a project to construct a linkage map for the two pheromone strains. Experimental conditions are described for polymerase chain reaction (PCR) multiplexing, which allows genotyping in two electrophoresis runs of eight and five markers each. In a sample of 27 individuals coming from one European locality, the number of alleles per locus ranged from one to 12, and gene diversity from 0 to 0.859. Seven loci showed a deficit of heterozygotes. Eleven loci cross‐amplify in the related Ostrinia furnacalis.  相似文献   

2.
To verify the validity of concerns about environmental safety of maize expressing insecticidal Cry toxins (referred to as Bt maize), we compared communities of ground beetles (Carabidae), rove beetles (Staphylinidae) and spiders (Araneae) in plots planted either with Bt maize cultivar YieldGard® or with the non‐transgenic parental cultivar Monumental. Each cultivar was grown on 5 plots of 0.5 ha for three consecutive years. To increase the field load of Cry toxin, the fully grown maize of the first study year was shredded to small pieces that were ploughed into the soil. Arthropods were collected in pitfall traps and determined to the species level. The abundance and species richness of all studied groups greatly varied over the season and between the seasons but without statistically significant differences between the Bt and non‐Bt plots. A single spider species and three ground beetle species dominated in the catches every year, whereas a set of 1–4 most abundant rove beetle species changed every year. Frequently occurring species were typical for most of Europe. The total counts of ground beetles, rove beetles and spiders collected once or twice per season are proposed to serve as bioindicators in the post‐market environmental monitoring (PMEM).  相似文献   

3.
Aims Twentieth‐century climate, the spatial pattern of tree establishment and positive feedback influence upper tree line ecotones. Here, I investigate how these factors interact to gain a more holistic understanding of how broad‐scale abiotic and local‐scale site conditions regulate tree establishment within upper tree line ecotones. Location A latitudinal gradient (c. 35–45° N) in the US Rocky Mountains. Study sites (n= 22) were located in the Bighorn (BH), Medicine Bow (MB), Front Range (FR) and Sangre de Cristo (SDC) mountain ranges. Methods Dendroecological techniques were used to reconstruct tree establishment dates that were compared with 20th‐century climate data using correlation and regime shift analyses. Spatial patterns of tree establishment were analysed by Ripley's K and used to determine local‐scale interactions capable of ameliorating broad‐scale climate inputs through positive feedback. Results Significant correlations (P < 0.01) between tree establishment and climate were confined to the FR, where a positive correlation was found with summer (June–August) and cool season (November–April) temperature range (Tmax?Tmin). These trees were almost exclusively situated in a random spatial pattern. Similar patterns exist in the BH, yet their establishment was contingent on the availability of local shelter in the lee of boulders. Trees in the MB and SDC were primarily clustered in space and had no significant correlations with climate. Considerable lag times exist between regime shift changes in climate towards more favourable growing conditions and corresponding shifts in tree establishment in all mountain ranges except the FR, where synchronous shifts occurred in the early 1950s. Main conclusions These results suggest that the influence of broad‐scale climate on upper tree line dynamics is contingent on the local‐scale spatial patterns of tree establishment and related influences of positive feedback. This research has important implications for understanding how vegetation communities will respond to global climate change.  相似文献   

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