Evaluation of 21 Thailand maize germplasms for resistance to leaf feeding spodoptera frugiperda (Lepidoptera: Noctuidae)

Authors: Abel, Craig; Scott, Marvin

Submitted to: Journal of Kansas Entomological Society
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/1/2020
Publication Date: 12/15/2020
Citation: Abel, C.A., Scott, M.P. 2020. Evaluation of 21 Thailand maize germplasms for resistance to leaf feeding spodoptera frugiperda (Lepidoptera: Noctuidae). Journal of Kansas Entomological Society. 93(1):97-102 . https://doi.org/10.2317/0022-8567-93.1.97.
DOI: https://doi.org/10.2317/0022-8567-93.1.97

Interpretive Summary: The fall armyworm is an economically important pest of maize in the Americas and is a recent invasive pest to Africa and southeast Asia. Control of this pest is challenging and the insect is resistant to several classes of insecticide and Bt-maize grown in Brazil, Puerto Rico and the southeastern U.S. The discovery of native sources of maize resistance to this is important to develop stable control methods. For this study, 21 maize germplasms developed in Thailand were evaluated for resistance to leaf feeding fall armyworm. The maize entries were grown in the field and plants infested with fall armyworm larvae. Damage to the maize leaves was recorded at 7 day and 14 day. Maize germplasm Ames 26254 was not different than a resistant check and germplasm PI 506347 and PI 690324 were not significantly different from Ames 26254. In total, five Thailand maize germplasms were considered moderately resistant to fall armyworm leaf feeding. These maize germplasms are publicly available for research and breeding.

Technical Abstract: Native to the Americas, the fall armyworm, Spodoptera frugiperda (J.E. Smith) (Lepidoptera:Noctuidae), is a recent invasive pest of Africa and Asia. This insect causes economic damage to maize (Zea mays L.) primarily through leaf and ear tissue feeding. The pest is resistant to several classes of insecticide and Bt-maize grown in some areas. Native resistance in maize to fall armyworm could be used with existing control tactics to overcome these issues. The objective for this study was to evaluate maize germplasm, developed from Thailand and maintained by the U.S. National Plant Germplasm System, 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 feeding damage were recorded at 7 and 14 days post infestation. Scores for maize germplasm Ames 26254 were not different than the resistant check, GT-FAWCC(C5), and germplasm PI 506347 and PI 690324 were not significantly different from Ames 26254. In total, five Thailand maize germplasms received 14-day damage scores of = 6.0 across both years of testing and were considered moderately resistant to fall armyworm leaf feeding. These maize germplasms are tropical and require breeding to adapt progeny for research in temperate areas.