Gossypolhemiquinone, a dimeric sesquiterpenoid identified in cotton (Gossypium)

The wild cotton, Gossypium thurberi is relatively free from insect herbivory in the wild. The dimeric sesquiterpenoid, gossypolhemiquinone (GHQ) was identified in the plant, but at low concentrations. At high concentrations GHQ exhibits a synergistic effect when fed with gossypol to Helicoverpa zea decreasing survival and lengthening days-to-pupation.163