Submitted to: Society for Invertebrate Pathology Meeting
Publication Type: Abstract only
Publication Acceptance Date: 8/29/1997
Publication Date: N/A
Citation: Interpretive Summary:
Technical Abstract: The Anagrapha falcifera nucleopolyhedrovirus (AfNPV) has shown potential for use as a bioinsecticide. Environmental conditions such as sunlight and rainfall can affect viral persistence, however, viral activity can be maintained with improved formulations. We produced 15 formulations of AfNPV by a spray drying technique and determined the effect (1) of the spray drying process on virus viability, (2) of different storage temperatures during a period of four months on viability, and (3) of persistence of viral activity after simulated rain or sunlight. The majority of ingredients tested included types of pregelatinized corn flours and kraft lignin. Droplet bioassays with Trichoplusia ni neonates were used to determine effect of spray drying and shelf life on activity of AfNPV. Cotton leaf bioassays were used to determine effect of artificial rainfall (5 cm in 1 hr) and solar stability (8 hrs exposure in a Suntest CPS) of formulations. Differences occurred among the formulations after spray drying. Virus spray dried only with lignin did not survive the process well, whereas formulations containing pregelatinized flours survived the best. Shelf life studies indicated that formulations containing nixtamalized corn flour, sugar, and oil survived well (90% OAR) for four months. Formulations containing both flour and lignin resisted solar degradation (65% OAR) and rainfall (75% OAR) better than other formulations. We believe these preliminary results demonstrate that natural products can enhance the stability, activity, and performance of viral biopesticides.