/24-7PressRelease/ - UNIVERSITY PARK, PA, September 04, 2008 - Scientists in a program led by Penn State, Clemson and Virginia Tech have discovered new Asian infestations of a dangerous pest that can devastate papaya crops—the papaya mealybug.
"As the world food crisis deepens, every effort to improve agricultural viability in developing countries is critical, and in India, papaya is a major fruit crop, so anything that threatens it warrants serious attention," says Dr. Ed Rajotte, Penn State professor of entomology and co-principal investigator for the South Asian site of the Integrated Pest Management Collaborative Research Support Program (IPM CRSP).
IPM CRSP is a consortium of integrated pest management scientists from U.S. universities and research institutions working to raise the standard of living in developing countries. This multi-million dollar venture, funded by the United States Agency for International Development, has research sites throughout the world. The South Asia site consists of India, Bangladesh and Nepal.
In May, 2008, the Clemson IPM CRSP team, led by economist Dr. Mike Hammig, principal investigator for the Southeast Asia site, identified papaya mealybug at the Bogor Botanical Gardens in Bogor, Indonesia. The Southeast Asia site includes Indonesia and the Philippines. In Bogor, the scientists collected samples and sent them off for identification to a specialist in mealybug taxonomy at the California Department of Agriculture. The taxonomist, Gillian Watson, confirmed the identification as papaya mealybug—an unarmored scale insect found in moist, warm climates. It was the first reported occurrence of papaya mealybug in Indonesia and Southeast Asia.
Two months later, on a trip to Tamil Nadu Agricultural University in Coimbatore, India, Dr. Muni Muniappan, Director of the IPM CRSP, recognized the telltale sticky residue on papayas he saw there as honeydew produced by papaya mealybug.
In each case, IPM scientists alerted government authorities and advised them on appropriate actions to take. These discoveries are crucial¬¬ - the sooner authorities can implement IPM programs to arrest the spread of the papaya mealybug, the better their chances of saving this lucrative tropical crop.
A highly effective crop protection strategy and an alternative to excessive pesticide applications, integrated pest management (IPM) aims to manage pests—such as insects, diseases, weeds and animals—by combining physical, biological and chemical tactics that are safe, profitable and environmentally compatible.
While papaya is an exotic fruit for us in the northern hemisphere, it is one that many of us use unknowingly in a variety of ways every day. Papain, a product of papaya, is used in the production of chewing gum and shampoo, toothpaste and tooth whiteners, as a meat tenderizer, and in the brewing and textile industries. In many tropical countries, papaya is an important commercial crop and a key component of the daily diet.
For this reason, attacks by the papaya mealybug are a serious threat. In Indonesia, India, countries in the Caribbean and South America, the Hawaiian Islands, and Florida, papaya means millions of dollars for farmers, middlemen and processors. In West Java, the scourge has wiped out most of the papaya plantations.
The papaya mealybug originated in Mexico and was first identified in 1992. In Mexico, natural enemies such as parasitoid wasps kept it in check. It wasn't until the papaya mealybug jumped countries and started proliferating where it had no natural enemies that it began to pose problems. In 1995, it was discovered on the Caribbean island of St. Martin. By the year 2000, it had spread to 13 countries in the Caribbean, to Florida in the United States, and to three countries each in Central and South America.
The papaya mealybug is a particularly devastating pest because it is polyphagous—it feeds on many things. The insect's host range includes over 60 species of plants: cassava, papaya, beans, eggplant, melons, hisbiscus, plumeria, pepper, sweet potato, tomato, citrus, mango and sour sop.
The good news is that the U.S. Department of Agriculture's Animal and Plant Health Inspection Service (APHIS) has developed a biological control program to tackle the pest. Biological control is an IPM tactic that pits natural enemies against pests. APHIS has identified three biocontrol agents including parasitic wasps that are highly effective at containing the mealybug. These natural enemies are being cultured in a laboratory in Puerto Rico and are offered free to countries that request them.
While the challenge of reclaiming the papaya plantations from the papaya mealybug seems daunting, Muniappan is optimistic. "The use of parasitoids has been very effective in Caribbean countries, in Latin American countries and in Florida, Guam and Palau," he says. "But we need to be vigilant."
For more information about the IPM CRSP, visit http://www.oired.vt.edu/ipmcrsp. For information about IPM, visit http://www.paipm.org.
# # #
Read more Press Releases from Kristie Auman-Bauer:Other Press Release Headlines:
