Abstract

The sex attractant of the rough bollworm was identified using gas chromatography and mass spectrometry (GC-MS) from female gland and air collections. Identified compounds were formulated into blends and tested in the field for attractiveness to males. The Gas chromatograph-mass spectrometry (GC-MS) analysis revealed 4 compounds, (E,E)-10,12-hexadecadienal, (E,E)-10,12-hexadecadienol, (Z)-11-hexadecenal and (Z)-11-octadecenal in a ratio of 4:1:1:1 in the gland extracts. (E,E)-10, 12-hexadecadienol was not detected in the air collections. Field bioassay showed the 2 components, (E,E)-10,12-hexadecadienal and (Z)-11-hexadecenal to be essential for activity of the blend. This blend was highly attractive to males only. 2 trap designs, the funnel and delta traps were tested and the delta trap was the better of the 2. Male response to attractant baited traps was found to be in the second half of the night, between 0200 and 0500 h. This was found to be synchronised to female calling time. Use of the attractant blend developed as part of the integrated pest management system in cotton is discussed.

Key words: Rough bollworm, (E,E)-10,12-hexadecadienal, (E,E)-10,12-hexadecadienol, (Z)-11-hexadecenal, (Z)-11-octadecenal, pheromone traps, gas chromatograph-mass spectrometry, sex attractant.