Location: Corn Insects and Crop Genetics ResearchTitle: Evaluation of eight maize germplasms developed in Ecuador for resistance to leaf-feeding fall armyworm
Submitted to: Southwestern Entomologist
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/3/2020
Publication Date: 3/26/2020
Citation: Abel, C.A., Coates, B.S. 2020. Evaluation of eight maize germplasms developed in Ecuador for resistance to leaf-feeding fall armyworm. Southwestern Entomologist. 45(1):75-78. https://doi.org/10.3958/059.045.0108.
Interpretive Summary: The fall armyworm causes economic damage to maize and control of this pest is challenging due to its protected feeding habit and resistance to several classes of insecticide and Bt-maize grown in some geographic regions. Native sources of maize resistance to this pest would be useful to develop more stable methods of pest control. For this study, eight maize germplasms developed in Ecuador were evaluated for resistance to leaf feeding fall armyworm. Maize germplasm Ames 26254 was as resistant to fall armyworm as a standard check used for these kind of studies. Two other maize germplasms developed in Ecuador were considered moderately resistant to fall armyworm. These maize germplasms are tropical and require breeding to adapt progeny for additional research and development in temperate areas.
Technical Abstract: The fall armyworm, Spodoptera frugiperda (J.E. Smith) (Lepidoptera:Noctuidae), causes economic damage to maize (Zea mays L.) and is resistant to several classes of insecticide and Bt-maize grown in some geographic areas. Native resistance in maize to fall armyworm could enhance existing control tactics. The objective for this study was to test maize germplasm developed from Ecuador for resistance to leaf feeding fall armyworm. Plants were grown in the field and artificially infested at the seven-leaf stage with fall armyworm. Visual rating scores for leaf damage were recorded at 7- and 14-days post infestation. Maize PI 487903, Ames 28851, and PI 390554 received 14-day scores of = 6.0 across both years of testing and were considered moderately resistant. PI 487903 was not different than resistant check, GT-FAWCC(C5). All of the germplasms tested are tropical populations that will require breeding to enable more research in temperate regions.