MANILA: Rice farmers should cut their use of pesticides that kill the natural predators of the planthopper, one of the most destructive pests of the cereal, the International Rice Research Institute said Friday.

The institute helped launch the 1970s “Green Revolution” in agriculture, lifting millions of Asians out of poverty through heavy use of pesticides. But it said it was time for a more environmentally friendly approach.

The Philippines-based IRRI said it had found that pesticides and the lack of ecological “diversity” in rice farms had reduced the predatory bugs and spiders that prey on planthoppers, a major rice pest in Asia.

“Fighting planthopper outbreaks calls for promoting natural planthopper enemy diversity and cutting down on pesticide use,” an IRRI statement said.

Many beneficial creatures that prey on planthoppers are killed inadvertently when insecticides are overused, it said.

The institute likewise said there was a need to diversify the varieties of rice being planted in the region, the world’s major producer and consumer of the staple food.

Growing three rice crops a year or using the same rice varieties for a long period can cause pest populations to adapt and grow in size, the institute said.

Thailand, with the IRRI’s support, banned the use of two insecticides in rice -- abamectin and cypermethrin -- three months ago because their misuse had encouraged major planthopper outbreaks.

Vietnam also began growing flowers near rice paddies in An Giang province in March to nurture planthopper predators, the IRRI said.

“We need to seriously rethink our current pest management strategies so we don’t just cope with current outbreaks, but prevent and manage them effectively in the long run,” Bas Bouman, head of IRRI’s environmental sciences unit, said.

The institute’s research helped bring about the “Green Revolution”, which relied on intensive use of fertiliser and pesticides to boost yields of staple foods in Asia and beyond.