Bioecology and prevalence of giant scale insect, Perissopneumon ferox Newstead (Homoptera: Monophlebidae) in Jahangirnagar University, Bangladesh

Abstract

The giant scale insect, Perissopneumon ferox Newstead is a major destructive, polyphagous, monophlebid pest that causes significant plant yield loss, typically found on woody plants, and is challenging to control. As a newly documented pest in Bangladesh, the present study deals with its biology, incidence, and ecological impacts both in the laboratory and in the field of Jahangirnagar University Campus (JUC), Dhaka, Bangladesh. Study of biology was conducted at room temperature, and a two-year field sampling was carried out on eight marked host plant species by visual counting in regular fortnightly surveys. A total number of 8028 insects in 2004-2005 on 5 host plant species and 1914 individuals in 2023-2024 on an equal number of host plant species, including three new plants were recorded. The host Albizia procera was the highest-infested tree. The pest insect peaks in June and gradually decreased to the end of the rainy season. No male was observed, and the female reproduced by thelytokous parthenogenesis, with laying eggs from mid-November to mid-December. Then the eggs hatched under the soil after more than two months of diapause in winter. In the laboratory study, its lifespan was recorded from 227-263 days including the nymphal period of 158.20±2.54 days. Its fecundity was 231±7.09. There were 13 types of ants found to be associated with this scale colony. The host plants and insect individuals declined in the latest study up to 19.5% and 76.16%, respectively, due to gradual deforestation. The current research will help understand the biology and ecological fitness of this insect, which is essential to figuring out its field management system.