ARS | Publication request: Transgenic maize plants expressing the Totivirus antifungal protein, KP4, are highly resistant to corn smut

Submitted to: Plant Biotechnology Journal
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: December 22, 2010
Publication Date: November 20, 2011
Repository URL: http://handle.nal.usda.gov/10113/54449
Citation: Allen, A., Islamovic, E., Kaur, J., Gold, S.E., Shah, D., Smith, T.J. 2011. Transgenic maize plants expressing the Totivirus antifungal protein, KP4, are highly resistant to corn smut. Plant Biotechnology Journal. 9:857-864. DOI: 10.1111/j.1467-7652.2011.00590.x/abstract

Interpretive Summary: Corn smut disease is worldwide and caused by the fungus Ustilago maydis. Resistance breeding for control of corn smut has not successfully controlled the disease. This research article shows that transgenic corn expressing an antifungal protein renders the plants highly resistant to corn smut disease. The antifungal protein is derived from a virus that naturally infects Ustilago maydis and its expression in corn had no damaging effects to plant growth. This approach has great potential for disease control and the possible eradication of the corn smut pathogen.

Technical Abstract: The corn smut fungus, Ustilago maydis, is a global pathogen responsible for extensive agricultural losses. Control of corn smut using traditional breeding has met with limited success because natural resistance to U. maydis is organ specific and involves numerous maize genes. Here, we present a transgenic approach by constitutively expressing the Totivirus antifungal protein KP4, in maize. Transgenic maize plants expressed high levels of KP4 with no apparent negative impact on plant development and displayed robust resistance to U. maydis challenges to both the stem and ear tissues in the greenhouse. More broadly, these results demonstrate that a high level of organ independent fungal resistance can be afforded by transgenic expression of this family of antifungal proteins.