Crop Biotech Update

Improving Maize Resistance to Head Smut

January 13, 2012

Head smut caused by fungus Sphacelotheca reiliana is one of the most devastating diseases in maize. Thus, deployment of resistant maize varieties is important to prevent widespread of the pathogen. Xianrong Zhao of the China Agricultural University and colleagues conducted a study to introgress a major resistance quantitative trait locus (qHSR1) into 10 maize inbred lines (Ji853, 444, 98107, 99094, Chang7-2, V022, V4, 982, 8903, and 8902) through marker-assisted backcrossing. The inbred lines used have excellent agronomic traits but are known to be susceptible to head smut. Each of those lines were crossed with Ji1037, which is completely resistant to head smut, and then followed by five generations of backcrossing to their own recurrent parent.

The 10 converted inbred lines exhibited improved resistance to head smut. Furthermore, the hybrids derived from the converted lines showed significant increase in resistance to head smut while retaining their favorable agronomic characteristics.

Subscribers of Molecular Breeding journal may get a copy of the research article at http://www.springerlink.com/content/cl66014663133267/