TNAU Agritech Portal :: Crop Protection

The mass production of the NPV is carried out in early fifth instar stage of S. litura, which yields maximum amount of the NPV. Therefore, in the host culture laboratory a continuous culture of the insects is maintained with proper handling procedures.
The larvae are grown in diet held in 5 ml glass vials. When the larvae reach the appropriate stage they are transferred to the virus production facility.
The NPV is multiplied by feeding the semi synthetic diet coated with a clean inoculum of the NPV that has previously been standardized.
This is accomplished by placing aliquots of 10 ml of the viral suspension of concentration 1 x 108 Polyhedral Occlusion Bodies (POB) in the centre over the diet surface either in glass vials and spreading the suspension uniformly all over the surface with a polished glass rod.
Larvae are released singly after 15 min. into each glass vial/cell and incubated at 25oC for 10 days.
The larvae begin to die from 5th day onward. The cadavers are collected individually and transferred to 500 ml plastic containers and frozen immediately until processing.
The processing method is similar to that of H. armigera.