Sökning: "natural enemies"

Visar resultat 1 - 5 av 32 avhandlingar innehållade orden natural enemies.

1. 1. Natural enemies: Functional aspects of local management in agricultural landscapes

   Författare :Helena Hanson; Biodiversitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Agricultural intensification; sustainable agriculture; land use; management intensity; landscape scale; ecosystem services; biological control; species trait; pesticides; predatory arthropods; parasitoids; pollen beetles;

   Sammanfattning : Agricultural intensification has raised the global food production but also caused major concerns about environmental and health effects, including contamination by pesticides. Pesticide applications may induce toxicity not only on the target pest species but especially on non-target species. LÄS MER

3. 2. Non-target Effects of Genetically Modified Trees

   Författare :Patrik Blomberg; Anders Wennström; Jan Stenlid; Umeå universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Genetically modified; GM trees; secondary metabolism; phytochemistry; Populus; transgenic; non-target effects; natural enemies; plant-pathogen herbivore interaction; environmental effects; parasitic fungi; herbivorous insect; Terrestrial ecology; Terrestisk ekologi;

   Sammanfattning : To date, few studies have focused on the effects of genetically modified trees (GM trees) on the environment. One concern with GM trees is that they may have unanticipated effects on non-target organisms, i.e. effects on organisms that are not direct targets of the genetically modified trait. LÄS MER

4. 3. Interactions between natural enemies and the dioecious herb Silene dioica

   Författare :Viktoria Pettersson; Barbara E. Giles; Lars Ericson; Pia Mutikainen; Umeå universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Silene dioica; Delia criniventris; Caryocolum viscariella; Microbotryum violaceum; plant-herbivore interactions; plant -pathogen interactions; sex bias; sex rato; successional gradients; fitness effects; Skeppsvik Archipelago; Terrestrial ecology; Terrestisk ekologi; ekologisk botanik; Ecological Botany;

   Sammanfattning : About 6% of all angiosperms are dioecious. This separation of sexual function to male and female individuals, and the fundamentally different patterns of reproductive resource allocation that follows that separation, are thought to have important ecological and evolutionary consequences for plant enemy interactions. LÄS MER

5. 4. Nitrogen, parasites and plants : key interactions in boreal forest ecosystems

   Författare :Joachim Strengbom; Lars Ericson; Gaius R Shaver; Umeå universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Critical loads; Deschampsia flexuosa; amino acids; mycorrhizal fungi; natural enemies; N deposition; N limitation; vegetational composition; Valdensia heterodoxa; Vaccinium myrtillus;

   Sammanfattning : In the work described in this thesis I studied how increases in nitrogen (N) inputs may affect plant community structure in boreal forest understorey vegetation. These phenomena were investigated in N fertilization experiments and along a national N deposition gradient. LÄS MER

7. 5. Ecology of pollinators, pests and natural enemies in agricultural landscapes : ensuring a sustainable supply of clover seeds

   Författare :Veronica Hederström; Sveriges lantbruksuniversitet; Sveriges lantbruksuniversitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

   Sammanfattning : The human population and its food consumption continues to grow and the environmental impact of meeting future food demands depends on how we expand the food supply. Already, agricultural intensification has led to biodiversity declines, which in turn can have direct and indirect effects on agricultural production. LÄS MER