Ecology, Behavior, and Biocontrol Studies on the Scarab Beetle, Maladera castanea (Coleoptera: Scarabaeidae) Infesting Strawberry Plants in Egypt

Abstract

Seasonal fluctuations of the scarab beetle, Maladera castanea that infest strawberry plants in the field, were conducted during the 2019/2020 season. The obtained results revealed that the highest population of scarabs was recorded in October, April, with averages of (61.2, 57.0, beetle/trap) under field conditions, the behavior of the adult scarabs to the preferred color and the activity periods was studied. The results showed that the white color was the most preferred one for the beetles, recording 37.0±2.6 adults/hour. The adults were assumed to be night activity during the period from 06:00 pm to 12.00 midnight, where the average number of M. castanea scarabs was recorded as 226.2± 8.1 adults/trap. Drying process for three weeks showed a 100% decrease in the population, while starvation process recorded a 90% decrease, after all, 100% decrease was recorded after four weeks. Entomopathogenic Nematodes (EPNs) were used on M. castanea at the laboratory, but its results showed that the third stage larvae have strong resistance to (EPNs). Under field conditions, the soil drench application of 24 cm of Lambda-Cyhalothrin 10% + 24 cm Abamectin 1.8% + 24 cm Emamectin 5% per feddan (4200 m) decreased 60% of M. castanea larvae, 3 days after treatment raised to 75 % 10 days after treatment. The hypopus of Caloglyphus audemansi mite was associated on M. castanea.