PESTS have ravaged about 4.500 hectares of rice crops in four provinces near the Cambodian-Vietnamese border, agriculture officials said on Wednesday.

Rithi Kun, deputy director of the Agriculture Department at the Ministry of Agriculture, Forestry and Fisheries, said Wednesday that brown "planthoppers", small pests that eat rice seedlings and thrive during the rainy season, have infested thousands of hectares of paddies in Svay Rieng, Prey Veng, Kandal and Takeo provinces.

Rithi Kun said his department was conducting extensive outreach efforts in the affected provinces to contain the problem. "We are working to educate farmers about how to disperse the brown planthoppers from their rice fields," he said.

The ministry is also offering payment to farmers who catch the planthoppers, thus preventing them from spreading to neighbouring farms. Farmers earn US$1.20 for every 10 kilograms of planthoppers they bring to their provincial agriculture office, said Thach Ratana, director of the agriculture department in Svay Rieng province.

Ngik Sron, director of the Department of Agriculture in Takeo province, said the brown planthopper population has flourished as farmers rely increasingly on chemical fertilisers and pesticides, which kill many of the planthoppers' natural predators.