Biological parameters and life table of Lipaphis pseudobrassicae (Hemiptera: Aphididae) (Davis, 1914) on kale (Brassica oleracea L. var. acephala)

Melo Júnior, LuizSilva, Paulo RamalhoFrança, SolangePortela, Gilson Lages

ABSTRACT Kale (Brassica oleracea L. var. acephala) is one of the main Brassicaceae crops cultivated in Brazil. Among the major pests of this crop in the country, there are the aphids Brevicoryne brassicae, Myzus persicae, and Lipaphis erysimi. Although Lipaphis pseudobrassicae has been reported on kale, no studies have investigated its bioecology on this host yet. Successful pest management requires knowledge of the biological and population parameters of the species in the environment where it occurs. Therefore, the objective of this study was to evaluate the biological and population parameters of the aphid that infests kale. Aphids were collected, screened, and mounted on permanent slides for taxonomic identification. Subsequently, a laboratory colony was established for biological studies and for the construction of the life table. For the life table, kale leaf discs were infested with two nymphs (0-24 h old) and monitored throughout the biological cycle. The parameters evaluated were the net reproductive rate (Ro), mean generation time (T), intrinsic rate of increase (rm), finite rate of increase (λ), and doubling time (DT). L. pseudobrassicae was the only species collected, showing a high biotic potential and population growth rate on B.oleracea under the studied conditions, with Ro = 92.61, T = 11.32, rm = 0.39, and λ = 1.49.