Ecology and Management of Paracoccus marginatus (Papaya Mealybug) (Hemiptera: Pseudococcidae) in the Indian Subcontinent — Achievements, and Lessons

Abstract

Paracoccus marginatus, first described in 1992, is native to Mexico. Accidentally it started spreading in the Caribbean in 1995. About 2008, it was reported from the Indian subcontinent and several other countries in the South- and Southeast-Asia. This polyphagous insect infests plants belonging to c. 50 families. Carica papaya (Caricaceae, papaya) and Manihot esculenta (Euphorbiaceae, cassava) are the principal species attacked by P. marginatus. In 1999, classical biological-control (hereafter, management) efforts to manage this insect were implemented by the U.S. Department of Agriculture (USDA). Carica papaya, M. esculenta, and Morus alba (Moraceae, mulberry) were heavily infested and suffered severe economic loss. Locally available natural enemies when trialled as biological-management agents were ineffective. This outcome instigated scientists to seek a classical biological-management option by introducing exotic parasitoids. Five potential parasitoids, Apoanagyrus nr. californicus, Pseudaphycus sp., Anagyrus loecki, Acerophagus papayae and Pseudleptomastix mexicana (all Encyrtidae) were obtained from Mexico in 1999. In the Indian subcontinent, three parasitoids (A. papayae, P. mexicana, and A. loecki) were first released in Sri Lanka in 2009 and in Tamil Nadu, India in 2010. They established well in the field and in five months they regulated the population of P. marginatus. Acerophagus papayae was found playing a major role in managing populations of P. marginatus.