Invasion of papaya mealybug, Paracoccus marginatus in Asia

Papaya mealybug Paracoccus marginatus (Hemiptera: Pseudococcidae) is a native to Mexico. It was first described from the specimens collected on cassava in 1955. By 2002, it has spread to most countries in the Caribbean including a few countries in South America. Between 2002 and 2006 it invaded Guam, Palau, Hawaiian Islands and Tinian in the Northern Mariana Islands. In 2008, it has been recorded in Bogor, Indonesia; Coimbatore, India; Colombo and Gampaha districts in Sri Lanka (L.D. Galanihi, pers. comm.); and northern part of Thailand (B. Napompeth, pers. comm.); and Joydebpur, Bangladesh in 2009. Paracoccus marginatus is a polyphagous pest and it has been recorded on several economic and weedy plants. On papaya, it infests along the veins of older leaves and all parts of young leaves and fruits. Affected older leaves dry up and shed prematurely, young leaves become curly, flowers and young fruits drop, and shoots appear bunchy. This mealybug has been effectively suppressed through classical biological control process by introducing parasitoids, Anagyrus loecki, Acerophagous papayae, and Pseudleptomastrix mexicana (Hymenoptera: Encyrtidae) from Mexico in to the Caribbean, South American and Pacific countries. All the five countries in Asia are considering developing classical biological control program to suppress PMB so that they can prevent its spread within their countries and also reduce the chances of its introduction to the neighboring countries. Neighboring countries should take up effective quarantine measures to prevent the introduction of PMB.