Bulletin of Entomological Research (2010) 100, 217-223
L.L. Fagan, A. McLachlan, C.M. Till and M.K. Walker (2010)
Synergy between chemical and biological control in the IPM of currant-lettuce aphid (Nasonovia ribisnigri) in Canterbury, New Zealand
Bulletin of Entomological Research 100 (2), 217-223
Abstract: Field trials were conducted at four Canterbury, New Zealand locations in 2005-06 to determine if the synergistic effects of biological control by natural enemies and standard drenching techniques controlled lettuce aphid populations throughout the entire growing season. Chemical usage significantly lowered aphid densities in the outer, wrapper and heart leaves compared to control plants at most times. However, in mid-summer, natural enemies, such as the brown lacewing (Micromus tasmaniae), 11-spotted ladybird beetle (Coccinella undecimpunctata) and small hoverfly larvae (Melanostoma fasciatum), were more than sufficient to control lettuce aphids without the use of insecticides. Drenching, in addition to natural enemy attack, appears to be required in early spring and late summer to maintain very low levels of lettuce aphid. Given the potential for imidacloprid resistance to develop, it may be advisable to restrict drenches to these key periods in order to allow populations of natural enemies to maintain control of prey populations. We recommend industry support the validation of action thresholds across different regions within New Zealand and focus on the seasonal biology of predators to assist growers with the sustainable long-term control of lettuce aphids. The inclusion of additional data into an economic model to compare pest damage with predator loading would be useful for growers in managing aphid problems. These results will assist in the continued improvement and development of a sustainable IPM strategy for lettuce aphids in New Zealand and elsewhere.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)
Link to article at publishers website
Research topic(s) for pests/diseases/weeds:
biocontrol - natural enemies
control - general
Research topic(s) for beneficials or antagonists:
general biology - morphology - evolution
population dynamics/epizootiology
Pest and/or beneficial records:
| Beneficial | Pest/Disease/Weed | Crop/Product | Country | Quarant.
|
|---|---|---|---|---|
| Nasonovia ribisnigri | Lettuce (Lactuca) | New Zealand | ||
| Micromus tasmaniae (predator) | Nasonovia ribisnigri | Lettuce (Lactuca) | New Zealand | |
| Melanostoma fasciatum (predator) | Nasonovia ribisnigri | Lettuce (Lactuca) | New Zealand | |
| Coccinella undecimpunctata (predator) | Nasonovia ribisnigri | Lettuce (Lactuca) | New Zealand |
