Monday, November 13, 2006

Gray Leaf Spot Evaluation of Elite Exotic Maize Inbreds.

Paul Nelson1, M.P. Jines1, and Major Goodman2. (1) North Carolina State Univ, 3008 A. Kings Court, Raleigh, NC 27606, (2) North Carolina State Univ, Dept. Of Crop Science, PO Box 7620, Raleigh, NC 27695-7620

Gray leaf spot (GLS) of maize (Zea mays) is caused by the fungus Cercospora zeae-maydis and thrives in humid environments that favor slow drying dews and late-season fogs. Today GLS is found throughout the Corn-Belt and is considered the most important foliar disease of maize in the U.S. The most efficient means of controlling GLS is through genetic resistance. Most of today’s commercial hybrids contain some level of genetic GLS resistance, but few are highly resistant. Thus, there is a need for additional sources of GLS-resistant germplasm in the U.S.  We have identified and screened 105 tropical and temperate-exotic maize inbreds in GLS trials in the mountainous regions of North Carolina. Many of the inbreds showed high levels of GLS resistance, including several lines that exhibit good yield potential as determined in previous studies at NC State. These lines include CML108, CML258, CML274, CML277, CML343, and Tzi16.