Submitted to: Society of Invertebrate Pathology
Publication Type: Abstract Only
Publication Acceptance Date: 8/27/1999
Publication Date: N/A
Citation: MCGUIRE, M.R., TAMEZ-GUERRA, P., BEHLE, R.W., SHASHA, B.S. FORMULATION OF ANAGRAPHA FALCIFERA NUCLEAR POLYHEDROSIS VIRUS FOR IMPROVED FIELD STABILITY. SOCIETY OF INVERTEBRATE PATHOLOGY. 1999.
Technical Abstract: The nucleopolyhedrosis virus isolated from Anagrapha falcifera is under commercial development for control of lepidopteran pests. Unformulated virus has limited field stability and generally loses activity within a few hours after application if exposed to direct sunlight. We have recently developed a method to combine previously discovered flour, lignin, and gluten-based adjuvants with active agents in a concentrated form and then spray dry them together. When the dried particle is applied to a leaf surface, the virus remains entrapped within the protective materials. Initial screens for formulation effectiveness centered on solar protection using cotton plants and a laboratory solar simulator. Field tests on cabbage leaves were used to examine residual activity. Four formulations of AfmNPV were selected for field testing based on initial screening. In addition, an experimental commercial formulation and unformulated virus were tested. Within four hours, the unformulated virus lost more than 50% original activity (OAR) and within 24 hours averaged only 20% OAR. Within 2 days, the commercial formulation had approximately 50% OAR. However, the four spray-dried formulations still averaged 80% OAR after 2 days and still had approximately 50% OAR after 3 days. Four days after application, all formulations had about 30% OAR. While these formulations are not rainfast, they do offer some potential for extending the residual activity of viruses in response to sunlight.