A study on insect pest occurrence of silver oak, Grevillea robusta A. Cunn. in Northern India

Abstract

Silver oak, Grevillea robusta A. Cunn. is an important exotic tree species component of urban forestry in India. However, the occurrence of insect-pests in exotics causes tremendous impact on the production and yield in nurseries as well-established plantations; consequently, reducing profits and inducing high expense to stakeholders. Thus, a detailed account of insect-pests infestation and their impact becomes important. Therefore, present study was undertaken to find out the insect pest occurrence on G. robusta in the nursery, plantation established at different geographical region of northern India from 2018-2022. The study result exhibited infestation of ten insect-pests for the first time on G. robusta. Six species were defoliator in nature viz. Ascotis selenaria, Chrysodeixis includens, Ectropis bhurmitra, Helicoverpa armigera, Hyposidra talaca, and Olene inclusa; while infestation of four species of sap sacking nature viz. Asterolecanium sp., Ceroplastes rusci, Drosicha stebbingi, and Oxyrachis tarandus. The seasonal incidence and nature of damage were also recorded for the first time of these insects on G. robusta. This is the first attempt to report insect-pests of G. robusta, which gave an overview of the possible potential threat in India. The study would be beneficial for future reference with respect to pest management of G. robusta, when the species is taken up for tree improvement program in the long run.

Keywords

• grevillea robusta
• defoliator
• sap feeder
• silver oak
• new record