Utilizing Diapause in a Sugarcane Borer (Lepidoptera: Crambidae) Laboratory Colony as a Cost Saving Measure

The ability to rear insects in the laboratory broadens the scope of research opportunities available to the scientist. Our laboratory routinely rears the sugarcane borer, Diatraea saccharalis (F.), for research in host plant resistance and biological control of this important sugarcane pest. Unfortunately, insect rearing is a costly process. One option to reduce cost is to hold a founder population in diapause during times when insects are not needed. These insects can then be brought out of diapause and allowed to reconstitute the colony. A procedure was developed to put larvae of the sugarcane borer into diapuase, hold these larvae for five months in cold storage, and then terminate diapause and allow the insects to complete development. The larvae were put into diapause by holding them at 18°C with a photoperiod of 12:12 (L:D) h. The diapausing larvae were then held for five months at 10°C and a photoperiod of 12:12 (L:D) h. In 2007 our laboratory diapaused 1024 sugarcane borer larvae, terminated our routine rearing, and held the founder colony until January of 2008. Seventy-three percent of the founder colony that diapaused in 2007 survived and produced healthy moths in 2008. We were not able to detect any adverse affects (i.e. malformed pupae) in the diapaused insects and we resumed normal rearing operations within 30 days of initiating diapause termination. This procedure saved our laboratory approximately $1600.00 in rearing supplies, but more importantly it allowed us to redirect our insectary manager to other critical tasks during that period of time that insects were not needed.