I started one year ago to save in my computer data about aphid distribution, host plants, resistance level, following some species such as Myzus persicae and Aphis fabae in fields near my city, since I would like to analyze their distribution in relation to climate change, chemical treatments and so on… this is why I read with great interest the paper published by Lamb, MacKay and Alyokhin in the Canadian Entomologist resulting from over 60 years of measurements and observations of three aphids species on potato plants.
According to their observations, the populations of Myzus persicae and Aphis nasturtii were less stable than previously studied natural populations of a native aphid species showing 3000-fold variation in their abundance and declined dramatically in some years. In contrast, the population of Macrosiphum euphorbiae, a native species, persisted throughout the 58 years and had variability in a potato crop similar to that of the previously studied native species.
The high population variability of M. persicae and A. nasturtii may be associated with their status as introduced invasive species suggesting that despite their presence on several plants introduced species may decrease dramatically in abundance year by year, whereas native species did not. Lastly, they showed that, even if aphid population dynamics are affected by year-to-year variation in weather, the contribution of weather to the population variation is not large.
Lamb RJ, MacKay PA, Alyokhin A (2011). Population variability and persistence of three aphid pests of potatoes over 60 years. Can. Entomol., 143, 91-101 DOI: 10.4039/n10-053
