Inhibition of chitin biosynthesis by buprofezin analogs in relation to their activity controlling Nilaparvata lugens Stål

Buprofezin (Applaud, 2-tert-butylimino-3-isopropyl-5-phenyl-3,4,5,6-tetrahydro-2H-1,3,5-thiadiazin-4-one) strongly inhibited the ³H]chitin synthesis from N-acetyl-d-1-³H]glucosamine in the brown rice planthopper, Nilaparvata lugens Stål. No inhibition was observed for ³H]-labeled protein biosynthesis from 5-³H]glucose or l-3,5-³H]tyrosine but ³H]-labeled nucleic acid synthesis from 5-³H]glucose was weakly reduced by buprofezin. The lethal activity of buprofezin analogs related well to their inhibitory potency against chitin biosynthesis in N. lugens nymphs.