Masaya Matsumura1, Sachiyo Sanada-Morimura1, Akira Otuka1, Shoji Sonoda2, Dinh Van Thanh3, Ho Van Chien4, Phan Van Tuong5, Phung Minh Loc5, Ze-Wen Liu6, Zeng-Rong Zhu7, Jian-Hong Li8, Gang Wu9, Shou-Horng Huang10. 1. NARO Kyushu Okinawa Agricultural Research Center, Koshi, Japan. 2. Institute of Plant Science and Resources, Okayama University, Kurashiki, Japan. 3. Plant Protection Research Institute, Ha Noi, Vietnam. 4. Southern Regional Plant Protection Center, Tien Giang, Vietnam. 5. Southern Pesticide Control & Testing Center, Ho Chi Minh City, Vietnam. 6. Nanjing Agricultural University, Nanjing, China. 7. Zhejiang University, Hangzhou, China. 8. Huazhong Agricultural University, Wuhan, China. 9. Fujian Agriculture and Forestry University, Fuzhou, China. 10. Chiayi Agricultural Experiment Station, Taiwan Agricultural Research Institute, Council of Agriculture, Chiayi, Taiwan, China.
Abstract
BACKGROUND: The two rice planthoppers, Nilaparvata lugens and Sogatella furcifera, have different life cycles in the regions of East Asia, the Red River Delta, and the Mekong Delta. The susceptibilities of these species to a range of insecticides have not previously been compared among the three regions over multiple years. Here, we describe the differences and similarities in insecticide susceptibilities of the two species among the three regions in 2006-2011. RESULTS: In all three regions in 2006 - 2011, N. lugens developed high and moderate levels of resistance to imidacloprid and thiamethoxam, respectively, but this species did not develop resistance to fipronil. In contrast, S. furcifera developed a high level of resistance to fipronil. The ranges in 50% lethal dose (LD50 ) values for N. lugens treated with both imidacloprid and thiamethoxam were similar over time between East Asia and the Red River Delta, and were different in the Mekong Delta. CONCLUSION: The results support the idea that resistant populations migrate from the Red River Delta region to East Asia. Therefore, continuous monitoring of the susceptibility of N. lugens to insecticides in the Red River Delta is very important for insecticide resistance management in East Asia.
BACKGROUND: The two rice planthoppers, Nilaparvata lugens and Sogatella furcifera, have different life cycles in the regions of East Asia, the Red River Delta, and the Mekong Delta. The susceptibilities of these species to a range of insecticides have not previously been compared among the three regions over multiple years. Here, we describe the differences and similarities in insecticide susceptibilities of the two species among the three regions in 2006-2011. RESULTS: In all three regions in 2006 - 2011, N. lugens developed high and moderate levels of resistance to imidacloprid and thiamethoxam, respectively, but this species did not develop resistance to fipronil. In contrast, S. furcifera developed a high level of resistance to fipronil. The ranges in 50% lethal dose (LD50 ) values for N. lugens treated with both imidacloprid and thiamethoxam were similar over time between East Asia and the Red River Delta, and were different in the Mekong Delta. CONCLUSION: The results support the idea that resistant populations migrate from the Red River Delta region to East Asia. Therefore, continuous monitoring of the susceptibility of N. lugens to insecticides in the Red River Delta is very important for insecticide resistance management in East Asia.