[HANOI] Governments across Asia need to improve their regulation of way that pesticides are marketed, and should ban certain pesticides from use in rice production completely, according to the International Rice Research Institute (IRRI), which is based in Manila, the Philippines.
IRRI released an action plan listing potential strategies for scaling back pesticide use and adopting ecological growing techniques at a conference in Vietnam last week (16 December), held under the title "Threats of Insecticide Misuse in Rice Ecosystems — Exploring Options for Mitigation".
In particular, it argued for a "greener game plan" to improve the management of brown planthoppers, which feed on rice sap and transmit plant viruses, and have in recent years destroyed millions of hectares of rice across Asia.
An outbreak usually occurs when the planthoppers' predators, such as spiders and insects, are killed off by the indiscriminate use or misuse of insecticides, said K.L. Heong, a senior scientist with IRRI.
Earlier this year, Thailand, which is the world's largest rice exporter, banned two pesticides — abamectin and cypermethrin — that according to IRRI are not only ineffective in controlling pests, but can lead to brown planthopper outbreaks.
In Vietnam, the world's second biggest rice exporter, cypermethrin is among the most popular insecticides.
But the Vietnamese government is expected to come out soon with a circular designed to phase out some pesticides, control pesticide marketing and encourage use of 'bio-pesticides', according to Bui Ba Bong, Vietnam's vice minister of agriculture and rural development.
"The misuse of pesticides threatens rice production, but also threatens the environment and the health of farmers and consumers," Bong told rice experts at the conference.
In the 1970s, aid programmes supported by organisations such as the US Agency for International Development (USAID) distributed most pesticides in developing countries. Usage has increased dramatically in recent years as pesticides have become sold widely on the open market, and advertised aggressively in rural areas, said Heong.
Pesticides are a "big problem" in many towns and villages in the country's fertile south, admits So Van Chien, director general of Vietnam's Southern Plant Protection Center.
According to Chien, only about 2,000 farmers in seven Vietnamese provinces are currently using insecticide-free growing methods, such as planting flowers that host beneficial insects that prey on the pests. Such efforts are further limited by floods and droughts, which kill flowers and other crops, he added.
See below for an IRRI video about fertiliser-free planthopper control: