Location: Corn, Soybean and Wheat Quality ResearchTitle: Potyvirus Resistance in Commercial Corn Germplasm: Vulnerability and Yield Penalties
Submitted to: Northeastern and Southern Corn Improvement Proceedings
Publication Type: Proceedings
Publication Acceptance Date: 4/4/2023
Publication Date: 4/4/2023
Citation: Jones, M.W., Nacci, C.A., Ohlson, E.W. 2023. Potyvirus Resistance in Commercial Corn Germplasm: Vulnerability and Yield Penalties. 74th Northeastern Corn Improvement Conference Proceedings (NECC-29), Wooster, Ohio. Page 1.
Technical Abstract: Maize dwarf mosaic virus (MDMV) and sugarcane mosaic virus (SCMV) are two of the most common maize viruses worldwide. Recent field surveys have found high incidence of MDMV in sweetcorn fields in Southern Ohio but not in fields of hybrid field corn. In this study, we examined current commercial field corn hybrids for resistance to MDMV and SCMV and the impact of these viruses on yield. More than 50 field corn hybrids were mechanically inoculated with MDMV or SCMV under field conditions in Wooster, OH. Among these hybrids, only one was found susceptible to MDMV whereas nearly all were susceptible to SCMV. Mean SCMV disease incidence averaged 60 - 76% over six trial years. Yield penalties associated with SCMV infection were assessed by comparing inoculated and mock inoculated treatments. Yields were reduced by between 19 - 25 bu/ac in the SCMV treatment, corresponding to an average yield penalty of approximately10%. MDMV and SCMV resistance in maize is controlled by three genes on chromosomes 6 (Wsm1), 3 (Wsm2), and 10 (Wsm3). While Wsm1 has been shown to confer resistance to MDMV, it is ineffective individually against SCMV. These findings suggest most commercial hybrids carry Wsm1, but are lacking Wsm1 + Wsm2 or Wsm1 + Wsm3 combinations. Incorporating these additional virus resistance loci would be an effective management strategy for SCMV.