Student Symposium: Alternatives to Chemical Control of Insects: Potential of Teflubenzuron for Diamondback Moth (Lepidoptera: Plutellidae) Management on Cabbage in Southern Florida

Abstract

The potential of the chitin synthesis inhibitor, teflubenzuron (CME 13406), for managing populations of diamondback moth (DBM), Plutella xylostella L., on cabbage was assessed during two consecutive growing seasons in southern Florida. In the first year, the effectiveness of two rates of teflubenzuron at managing DBM populations was compared with those of three commonly used insecticides, fenvalerate, methamidophos, and methomyl in combination with Bacillus thuringiensis var. kurstaki, applied at recommended rates. In the second year, the effects of different treatment intervals (7, 14 or 21 days) of teflubenzuron on DBM management were assessed. Teflubenzuron was more effective than other insecticides at suppressing DBM populations and protecting plants. The percentages of marketable cabbage heads were 98, 98, 83, 80, and 50% on plants treated with teflubenzuron at 0.022 and 0.044 kg ai/ha, methomyl in combination with B. thuringiensis, fenvalerate, and methamidophos, respectively, and was 17% in nontreated plots. In the second year, teflubenzuron (0.033 kg ai/ha) was consistently more effective than other insecticides at suppressing DBM populations. DBM populations and the percentages of marketable heads did not differ among plants treated with teflubenzuron at 7-, 14-, and 21-day intervals, suggesting that the negative effects of teflubenzuron on DBM were persistent. The potential importance of teflubenzuron in DBM management programs in Florida is discussed.