Repellent compositions and genetic approaches for controlling huanglongbing

A method for controlling Huanglongbing (HLB) in citrus plants comprising expressing at least one isolated gene encoding a polypeptide having β-caryophyllene synthase and/or α-copaene synthase activity in citrus plants to produce additional β-caryophyllene, α-copaene, or combinations thereof in order to repel Diaphorina citri and/or Tryoza erytrae psyllid insects so as to control HLB.

A method for controlling Huanglongbing (HLB) disease of citrus plants comprising applying purified β-caryophyllene, α-copaene, or combinations thereof, which repels Diaphorina citri and/or Tryoza erytrae psyllid insects, to citrus plants so as to control the HLB disease of citrus plants.