Bio-Insecticidal Potential of Nucleopolyhedrovirus and Granulovirus Mixtures to Control the Fall Armyworm Spodoptera frugiperda (J.E. Smith, 1797) (Lepidoptera: Noctuidae)

Abstract

The ability of the isolate VG008 of S. frugiperda granulovirus (SpfrGV) to enhance the infectivity of the isolate SfCOL of S. frugiperda multiple nucleopolyhedrovirus (SpfrMNPV) was evaluated on S. frugiperda larvae. Bioassays were performed with mixtures by using different proportions 90%:10% (M1), 95%:5% (M2) and 97.5%:2.5% (M3) of SfCOL:VG008, respectively. All mixtures showed higher insecticidal activity that SfCOL. The mixture M3 showed the highest enhancement of SfCOL reducing 11.40 times the Mean Lethal Concentration and 96 h in the Mean Time to Death. The enhancer activity of proteins derived from VG008 (GVPs) were also evaluated in mixture with SfCOL. The GVPs increased 27% larval mortality caused by SfCOL and damaged the peritrophic membrane of S. litura larvae, suggesting that the key point in this enhancing activity is the initial step of the larva colonization, the midgut infection. M3 was formulated and evaluated under greenhouse conditions in maize plants using different doses. The highest efficacy was obtained with the highest dose of M3 (8 × 1011 OBs/ha), which was similar to that found when formulated SfCOL was applied using an approximately twofold higher dose. The viral mixture M3 was selected as the active ingredient for developing a new biopesticide for a more efficient management of the pest in the field.

Viruses of the Fall Armyworm Spodoptera frugiperda: A Review with Prospects for Biological Control

“…Most baculoviruses cause lethal infections to insects and infect the larval stages of insect species. Infected larvae show lethargic behavior, a swollen body with whitish pale-discoloration, death, and often liquefaction of the larvae (Table 1) [65,66]. Additionally, some baculoviruses induce behavior manipulations in caterpillars, which includes hyperactivity and climbing to the top of the plant or tree before liquefaction [67,68].…”

Maize mycorrhizas decrease the susceptibility of the foliar insect herbivore Spodoptera frugiperda to its homologous nucleopolyhedrovirus

“…In addition, application of broad‐spectrum insecticides can also result in insect resistance 8 and collateral damage to populations of natural enemies 9 . Because of this, alternative environmentally friendly pest control methods are needed to reduce pesticide use by employing natural pest regulation within an agroecological approach 10 …”

Caracterización de baculovirus autóctonos para el control de la oruga militar tardía (<i>Spodoptera frugiperda</i>)

“…79,154 Esto sugiere que la función potenciadora de SfGV cuando es aplicado en conjunto con SfMNPV podría ser explicado en parte gracias a la presencia de ambas Enhancin en su OB. 101,119 Nuestros datos proteómicos sugieren que las proteínas pertenecientes a la familia de Epap95/Spfr101 no solo son componentes específicos que los granulovirus han adaptado para su uso en el OB, sino que también muestra que estas proteínas se encuentran en elevados niveles de abundancia, sugiriendo un rol importante para estas proteínas. El hecho de que en un contexto in vitro esta proteína es capaz de formar agregados potencialmente amiloides (como lo demuestra su perfil de agregación in silico), podría indicar que esta proteína tiene un comportamiento similar al de LEF-10, la cual se ha demostrado recientemente que puede actuar como una proteína tipo prión.…”

“…Recientemente, se ha demostrado que la formulación conjunta de SfMNPV como principio activo con dosis más bajas de SfGV como potenciador presentan una elevada eficacia para el control de S. frugiperda. 101…”

“…Sin embargo, este virus ha sido empleado como agente potenciador del nucleopoliedrovirus de Spodoptera frugiperda (SfMNPV). 101,119 En este sentido, los factores genéticos y proteicos que determinan la letalidad y la capacidad potenciadora de los granulovirus permanecen todavía poco claros. Dentro del género Betabaculovirus, es posible identificar dos grupos diferentes a nivel filogenético, clado a y clado b.…”