Measuring population fluctuation of jatropha stem-borer [Cophes notaticeps (Marshall)] in the Brazilian Cerrado using a new trap.

This study aimed to monitor the population fluctuation of Cophes notaticeps (Marshall) (Coleoptera: Curculionidae) in a jatropha (Jatropha curcas L.) plantation in the Federal District, Brazil, through the use of a new trap, combined with different attractive lures and trap colors. The study was conducted at Embrapa Cerrados (Planaltina/DF) in a field trial with 720 plants. The new trap, named CPAC16, was made with PVC pipes (100 mm in diameter) of about 40 cm in length, with a window (8 × 10 cm2) in its center to enable insect access. A lure compartment was fixed on the inside of the trap`s top, and a pot, containing water and detergent, was placed at its bottom to collect the insects. The traps were painted in red, yellow, blue and green. Molasses, ethanol and pineapple were used as attractive lures. The traps were in the field trial area between May 2013 and April 2014 and the insects were collected weekly. The incidence of plants presenting damage caused by C. notaticeps was evaluated in the beginning and at the end of the study. The CPAC16 trap proved efficient in monitoring C. notaticeps. About 3494 of C. notaticeps adults were collected during the study. There were no significant differences among traps painted with different colors. The most attractive lure was molasses collecting 75.2% (n = 2627) of the specimens. Although the population peak occurred in December (n = 1162), C. notaticeps were collected throughout the year. The incidence of plants attacked by C. notaticeps ranged from 66.4% (start) to 100% (end).