02716naa a2200277 a 450000100080000000500110000800800410001902400260006010000200008624502180010626000090032450000960033352017410042965000230217065000200219365000170221365300150223065300180224570000200226370000190228370000220230270000230232470000180234770000170236577300560238221367152022-11-21       2022    bl uuuu     u00u1 u    #d7 a10.1002/ps.6729.2DOI1 aFARIA, M. R. de  aEvaluation of key parameters for developing a Metarhizium rileyi-based biopesticide against Spodoptera frugiperda (LepidopterabNoctuidae) in maize: laboratory, greenhouse, and field trials.h[electronic resource]  c2022  aNa publicação: Marcos Faria; Daniela Aguiar Souza; Francisco Guilherme Vergolino Schmidt.  aBackground: The entomopathogenic fungus Metarhizium rileyi is well known to cause natural infections in some caterpillars. In this multiyear study, we carried out lab, greenhouse and three field trials with the aim of developing a sustainable option for control of the fall armyworm (FAW) in maize. Association of Metarhizium rileyi with Spodoptera frugiperda baculovirus (SfMNPV) and delivery strategies were also investigated in this study. Results: The selected isolate (CG381) was effective in the lab at a low concentration (ca. 4 × 103 conidia.cm-2 ), killing more than 95% of FAW larvae within 8 days. In the greenhouse assay, applications of conidia suspended in water or as dry powder in maize whorls (ca. 6.3 × 106 conidia per plant) produced similar larval mortalities (88-96%). In the field trials, conventional spraying of unformulated conidia (0.6 and 1.2 × 1012 conidia.ha-1 ) caused low larval mortalities (27-31%). Simultaneous application of either unformulated or oil-based formulations of M. rileyi conidia and S. frugiperda baculovirus (SfMNPV) to plant rows caused larval mortalities comparable to each of the pathogens applied alone. However, when a formulation containing both pathogens was sprayed directly into the whorls, the overall mortality of S. frugiperda larvae due to pathogens (mostly to M. rileyi infections) reached ca. 59%, two-fold higher than the other treatments with conventional spraying, whereas in the control the overall mortality was only 1%. Conclusion: Optimizing exposure of S. frugiperda larvae to inoculum of virulent entomopathogens through directed applications to maize whorls is critical to produce satisfactory mortality levels and is promising for integrated pest management.  aBiological control  aEntomopathogens  aPest control  aBiocontrol  aMycopesticide1 aSOUZA, D. A. de1 aSANCHES, M. M.1 aSCHMIDT, F. G. V.1 aOLIVEIRA, C. M. de1 aBENITO, N. P.1 aLOPES, R. B.  tPest Management Sciencegv. 78, p. 1146-1154, 2022.