Alexandra Bernal1, Oihane Simón1, Trevor Williams2, Delia Muñoz3, Primitivo Caballero1,3. 1. Instituto de Agrobiotecnología, CSIC-Gobierno de Navarra, Mutilva Baja, Spain. 2. Instituto de Ecología AC, Xalapa, Mexico. 3. Dpto. Producción Agraria, Universidad Pública de Navarra, Pamplona, Spain.
Abstract
BACKGROUND: A Chrysodeixis chalcites nucleopolyhedrovirus from the Canary Islands (ChchNPV-TF1) has proved to be effective for control of Chrysodeixis chalcites on banana crops. Commercialization of this virus as a bioinsecticide requires an efficient production system. RESULTS: The sixth instar (L6 ) was the most suitable for virus production, producing 1.80 × 1011 occlusion bodies (OB)/larva and showed a lower prevalence of cannibalism (5.4%) than fourth (L4 ) or fifth (L5 ) instars. Inoculation of L6 at 24 h post molting produced six times more OB (5.72 × 1011 OB/larva) than recently molted L6 larvae (1.00 × 1011 OB/larva). No significant differences were recorded in mean time to death (165-175 h) or OB production per larva (3.75 × 1011 to 5.97 × 1011 ) or per mg larval weight (1.30 × 1011 to 2.11 × 109 ), in larvae inoculated with a range of inoculum concentrations (LC50 -LC90 ). Groups of infected L6 larvae reared at a density of 150 larvae/container produced a greater total number of OBs (8.07 × 1013 OB/container) than lower densities (25, 50 and 100 OB/container), and a similar number to containers with 200 inoculated larvae (8.43 × 1013 OB/container). CONCLUSION: The processes described here allow efficient production of sufficient OBs to treat ∼ 40 ha of banana crops using the insects from a single container.
BACKGROUND: A Chrysodeixis chalcites nucleopolyhedrovirus from the Canary Islands (ChchNPV-TF1) has proved to be effective for control of Chrysodeixis chalcites on banana crops. Commercialization of this virus as a bioinsecticide requires an efficient production system. RESULTS: The sixth instar (L6 ) was the most suitable for virus production, producing 1.80 × 1011 occlusion bodies (OB)/larva and showed a lower prevalence of cannibalism (5.4%) than fourth (L4 ) or fifth (L5 ) instars. Inoculation of L6 at 24 h post molting produced six times more OB (5.72 × 1011 OB/larva) than recently molted L6 larvae (1.00 × 1011 OB/larva). No significant differences were recorded in mean time to death (165-175 h) or OB production per larva (3.75 × 1011 to 5.97 × 1011 ) or per mg larval weight (1.30 × 1011 to 2.11 × 109 ), in larvae inoculated with a range of inoculum concentrations (LC50 -LC90 ). Groups of infected L6 larvae reared at a density of 150 larvae/container produced a greater total number of OBs (8.07 × 1013 OB/container) than lower densities (25, 50 and 100 OB/container), and a similar number to containers with 200 inoculated larvae (8.43 × 1013 OB/container). CONCLUSION: The processes described here allow efficient production of sufficient OBs to treat ∼ 40 ha of banana crops using the insects from a single container.
Authors: Priscila Stinguel; Carlos Eduardo Costa Paiva; Vitor Zuim; Ana Clara Thezolin Azevedo; Fernando Hercos Valicente; Hugo José Gonçalves Dos Santos Júnior Journal: Neotrop Entomol Date: 2021-09-29 Impact factor: 1.434