Abstract

1. Seasonal population growth rates for the pea aphid, Acyrthosiphon pisum Harris, were determined in three different host plant habitats; alfalfa, Medicago sativa (L.), clover, Trifolium pratense (L.), and peas, Pisum sativum (L.); over four years and eight places, It was possible to estimate a common intrinsic rate of increase for each host plant habitat.2. An analysis of the relative influence of temporal, spatial and host plant habitat variation showed that the host plant habitat was most important in determining the growth rates of the populations, both in rate of build-up and decline.3. Patterns of alate production in the three different habitats differed substantially between the annual peas and the two perennial legumes. During the summer, alate production was large and rapid in peas and remained low and constant in clover and alfalfa4. Parasitism was highest in peas. The species composition of parasitoids differed between crops.5. Aphids in annual peas had a higher intrinsic rate of increase and a faster rate of decline than in the two perennial legumes. This explains the presence of both mi,oratory and sedentary forms among pea aphids.

Keywords

Acyrthosiphon pisum; annual host; perennial hosts; migration; plant-insect interaction; parasitism; life-history strategy

Published in

Ecological Entomology
1996, Volume: 21, number: 3, pages: 235-240
Publisher: BLACKWELL SCIENCE LTD

SLU Authors

• Bommarco, Riccardo

  • Department of Entomology, Swedish University of Agricultural Sciences
    

• Ekbom, Barbara

  • Department of Entomology, Swedish University of Agricultural Sciences
    

UKÄ Subject classification

Ecology


Publication identifier

DOI: https://doi.org/10.1111/j.1365-2311.1996.tb01240.x

Permanent link to this page (URI)

https://res.slu.se/id/publ/40426