Changes in Susceptibility of the Aphid, Myzus persicae and the Predator, Chrysoperla carnea to Some Insecticides on Sugar Beet Plants

Aphid infestations represent a major threat to sugar beet production in Egypt, necessitating effective and sustainable control strategies. This two-year field study [Insecticide applications on September 19th (2024) and September 22nd (2025)] to evaluated the efficacy of some insecticides: Beta cyfluthrin (Pyrethroid), Flonicamid (anti-feeding agent), Acetamiprid, Spinosad and Thiamethoxam against Myzus persicae (green peach aphid) and the predator, Chrysoperla carnea, on sugar beet plants at the farm of Sakha Agricultural Research Station, Kafr El-Sheikh. All insecticides demonstrated high efficacy, achieving 82.37 % to 94.58 % reduction in aphid numbers and 66.89 to 90.85 % reduction in lacewing numbers 10 day after treatment through the first and second seasons, respectively. Therefore, Beta cyfluthrin provided rapid initial knockdown (66.85 and 66.89 % in the first season and 68.55 and 90.85 % in the second season, followed by Flonicamid that exhibited on aphid and lacewing (66.82 and 68.33 % in the first season and 68.07 and 66.70 % in the second season for both Myzus persicae and Ch. carnea, respectively.) and a delayed but sustained anti-feeding effect, Spinosad displayed moderate initial control but strong residual activity. Abiotic factors are significantly increased, associated with aphids and lacewings, as well as, predators, during two consecutive seasons. Therefore, a highly significant correlation was found between the aphid and the lacewing. The overall effect of predators on pests was significant. One-way ANOVA revealed insignificant differences among insecticide classes at different time points. The findings highlight the importance of selecting insecticides based on their modes of action, efficacy timelines and their activity against aphids for integrated pest management (IPM) programs.