Interactions of two aphid species on the african eggplant, sorrel and amaranth

Aphids (Homoptera: Aphididae) are polyphagous insects which can be found on
several crops in temperate zones, as well as in the tropics. The multiplication of Aphis
gossypii Glover (C9 cucumber, Burk cotton and Pipo pepper strains) and Myzus
persicae Sulzer was studied in the laboratory on three plant species: African eggplant,
Solanum aethiopicum, sorrel, Hibiscus sabdariffa, and amaranth, Amaranthus spp.
Periodic counts were carried out to monitor population growth. The multiplication rate
of M. persicae wass higher than that of A. gossypii when these two species were
present together on eggplant. Amaranth was less suitable for the development of
both species, but Myzus persicae again had a better multiplication rate than Aphis gossypii.
This study illustrated the importance of considering not only one pest species, but
the whole herbivore guild, especially when biological control is important.