Seasonal abundance of the serious pest Seychellarum mealybug Icerya seychellarum (Westwood) (Hemiptera: Monophlebidae) and its predator rodalia cardinalis (Coleoptera: Coccinellidae) on mango trees in Giza Governorate, as well as its control by bioinsecticides

Abstract

The present study was carried out throughout two successive years (2022 – 2023) to determine Seasonal abundance of the serious pest Icerya seychellarum (Westwood) (Hemiptera: Monophlebidae) infested mango trees and its associated predator Rodolia cardinalis (Mulsant) (Coleoptera: Coccinellidae) as well as its control by bioinsecticides. The seasonal abundance of I. seychellarum was studied in Giza Governorate on mango trees. The obtained results showed that the maximum numbers of individuals were 5720, 2120, 1200 and 455 individuals for nymphs, non-ovipositing, ovipositing, the predator R. cardinalis, respectively during 2022. While the season 2023, that the maximum numbers of individuals were 5420, 1744, 1080 and 403 individuals for nymphs, non-ovipositing, ovipositing, the predator R. cardinalis, respectively. On the other hand, the maximum and minimum temperatures were significant on the population of I. seychellarum while the percentage of relative humidity and the population of predator under consideration are nonsignificant. Nine natural compounds and essential oils, mineral oil (Tiger), Beauveria bassiana, Metarhizium anisopliae, Azadirachtin indica, citrus oil, buprofezin (Applaud), garlic oil, actellic and spinosad were evaluated for controlling the mealybug, I. seychellarum as well as its predator R. cardinalis on mango in Giza Governorate on during October 2022 and 2023. The obtained results revealed that actellic have given the highest reduction (%) values for I. seychellarum and its predator R. cardinalis during October 2022 and 2023.. In 2022 and 2023 in Giza, the maximum reduction % values of actellic for I. seychellarum and its predator R. cardinalis, were (91.13 and 70.94%) and (92.19 and 73.06%), respectively. On the other hand, the rest of the natural compounds ranged between 76.6-90.01 and 74.27-91.21 during 2022 and 2023, respectively.