The coconut hispine beetle, Brontispa longissima (Gestro), is the most destructive pest of palm trees. We tested the efficiency of a selection of insecticides and established a efficient quarantine treatment to eliminate this pest on palm trees for export. In laboratory test, when applying 50% Propoxur, 40.8% Chlorpyrifos, and 2.8% Cyhalothrin topically, the mortality rate for both adults and larvae was 100% within 24 h. The shortest KT50 (< 5 min) of larvae and adults was obtained by the treatment of Propoxur at a diluted rate of 500 X. The longest KT50 for larvae was 8.45 min when treated with 1,250 X Cyhalothrin and for adults it was 1,250 X Chlorpyrifos. The dipping treatment of a single unopened spear leaf of the coconut palm tree for 5 seconds with 4 selected insecticides, resulted in a 100% control rate with 1,000 X concentration of 40.8% Chlorpyrifos, 2.8% Cyhalothrin, and 85% Carbary 24 h after treatment. In addition, 50% Propoxur could reach a 100% control rate within 48 h after treatment. In the greenhouse, spraying unopened spear leaves of the coconut palm tree infested by this pest with 1,000 X Propoxur and Chlorpyrifos showed a 100% control rate of the beetles in 4 d and 6 d after treatment, respectively. Although a few eggs hatched in both the dipping and the spraying tests, no living larvae were observed. Field tests, consisting of twice spraying 5 different insecticides on infested coconut trees, showed that 50% Propoxur WP and 40.8% Chlorpyrifos EC at a diluted rate of 1,000 X reached a 100% control rate in 14 days. Either of these two insecticides at a diluted rate of 1,000 X is recommended for quarantine treatment, and the palm trees for export should be sprayed twice in 7 day intervals. Efficient control efficiency is ensured with one additional treatment 24 h before loading the trees that are to be exported.
The coconut hispine beetle, Brontispa longissima (Gestro), is the most destructive pest of palm trees. We tested the efficiency of a selection of insecticides and established a efficient quarantine treatment to eliminate this pest on palm trees for export. In laboratory test, when applying 50% Propoxur, 40.8% Chlorpyrifos, and 2.8% Cyhalothrin topically, the mortality rate for both adults and larvae was 100% within 24 h. The shortest KT50 (< 5 min) of larvae and adults was obtained by the treatment of Propoxur at a diluted rate of 500 X. The longest KT50 for larvae was 8.45 min when treated with 1,250 X Cyhalothrin and for adults it was 1,250 X Chlorpyrifos. The dipping treatment of a single unopened spear leaf of the coconut palm tree for 5 seconds with 4 selected insecticides, resulted in a 100% control rate with 1,000 X concentration of 40.8% Chlorpyrifos, 2.8% Cyhalothrin, and 85% Carbary 24 h after treatment. In addition, 50% Propoxur could reach a 100% control rate within 48 h after treatment. In the greenhouse, spraying unopened spear leaves of the coconut palm tree infested by this pest with 1,000 X Propoxur and Chlorpyrifos showed a 100% control rate of the beetles in 4 d and 6 d after treatment, respectively. Although a few eggs hatched in both the dipping and the spraying tests, no living larvae were observed. Field tests, consisting of twice spraying 5 different insecticides on infested coconut trees, showed that 50% Propoxur WP and 40.8% Chlorpyrifos EC at a diluted rate of 1,000 X reached a 100% control rate in 14 days. Either of these two insecticides at a diluted rate of 1,000 X is recommended for quarantine treatment, and the palm trees for export should be sprayed twice in 7 day intervals. Efficient control efficiency is ensured with one additional treatment 24 h before loading the trees that are to be exported.