Mass production and purification of Euproctis chrysorrhoea (L.) nuclear polyhedrosis virus.

The rearing of larval Euproctis chrysorrhoea (L.) on an artificial wheatgerm diet is described. The larvae grew well on the diet, but took over ten weeks to complete their development, reflecting their prolonged life-span in the field. Using these larvae it was possible to mass produce a nuclear polyhedrosis virus (NPV) isolated from this species, with a view towards its use as a biological insecticide. A mean of 5.86 x 10(9) semi-pure NPV polyhedral inclusion bodies/g virus-killed larva was produced. The purification method described (simple centrifugation) removed over 99% of contaminant urticaceous hairs. Further purification through a sucrose gradient removed more hairs, but also resulted in a loss of NPV of about 35%.