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Population dynamics of the cabbage aphid, Brevicoryne brassicae (L.).
| Content Provider | Semantic Scholar |
|---|---|
| Author | Hughes, R. D. |
| Copyright Year | 1963 |
| Abstract | The population dynamics of the cabbage aphid (Brevicoryne brassicae) were studied on Maris Kestrel kale during the summer months, in Vancouver B r i t i s h Columbia, Canada. The object was to describe the temporal variation in numbers, age d i s t r i b u t i o n , and quality of B^ brassicae in terms of quantitative relationships between the aphid and i t s b i o t i c and a b i o t i c environment, using a simulation model. A technique was developed whereby aphid fecundity and developmental time could be estimated for aphids within the population. Aphid fecundity and rate of development decreased continuously through the season, probably in response to changes in plant qu a l i t y . The plant rarely posed an upper l i m i t on aphid increase, but populations consistently showed an i n i t i a l maximal rate of increase followed by a l e v e l i n g off, and eventual population decline in the autumn. Evidence presented, suggests that syrphid predation was largely responsible for the major midseason s h i f t s in the rate of increase of the aphid. Thompson's(1924) 'random search' model did not adequately represent syrphid predation, and further detailed studies are required. Decreasing aphid developmental and reproductive rates, production of oviparae, predation, and leaf f a l l , were probably responsible for population declines in the autumn. The cabbage aphid system is compared with that described by Hughes(l963) and Hughes £• Gi lbert ( 1968) . The problems of generality, and b i o l o g i c a l control are discussed. |
| Starting Page | 393 |
| Ending Page | 393 |
| Page Count | 1 |
| File Format | PDF HTM / HTML |
| DOI | 10.2307/2600 |
| Alternate Webpage(s) | https://open.library.ubc.ca/media/download/pdf/831/1.0095622/1 |
| Alternate Webpage(s) | https://doi.org/10.2307/2600 |
| Volume Number | 32 |
| Language | English |
| Access Restriction | Open |
| Content Type | Text |
| Resource Type | Article |
