Pest Management Science Pest Manag Sci 62:434–439 (2006) Efficacy of noviflumuron gel bait for control of the German cockroach,

Abstract: The insecticidal activity of a cockroach gel bait containing a chitin synthesis inhibitor, noviflumuron, was evaluated using laboratory and field strains of the German cockroach, Blattella germanica (L.). Noviflumuron gel bait (0.01–5mgg−1) caused ≥90 % nymphal mortality to laboratory and field strains of B. germanica in choice tests after 11 and 19days of continuous exposure respectively. In 1m × 1m bioassay arenas, laboratory strain B. germanica population levels exposed to 5mgg−1 noviflumuron bait or 0.1mgg−1 fipronil gel bait were significantly lower than untreated population levels after 3weeks and 1week of exposure respectively. Various noviflumuron bait exposure periods (2, 4 and 7weeks) caused similar population reductions, with a mean of 99.3 (±0.3) % at 7weeks. Fipronil gel bait caused 100 % population reduction at 2weeks post-exposure. The control population increased 89.0 % at 7weeks. In a simulated kitchen experiment withmixed stage laboratory populations, cockroach trap catches decreased 96.8 (±2.0) % at 8weeks in the 0.5mgg−1 noviflumuron bait treatment. The trap catches in the control increased 506.5 (±493.7) % during the same period. Trap catch reduction by 0.1mgg−1 fipronil gel bait reached 100 % at 4weeks. Noviflumuron bait caused significantly lower nymph/total ratios to B. germanica populations in bioassay arenas from 2weeks after exposure, demonstrating its effectiveness as a control agent for B. germanica with a pattern of activity similar to that expected from a chitin synthesis inhibitor