|LENNON, JILL - North Carolina State University|
|GOODMAN, MAJOR - North Carolina State University|
Submitted to: Crop Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/15/2015
Publication Date: 1/1/2016
Citation: Lennon, J., Krakowsky, M.D., Goodman, M., Flint Garcia, S.A., Balint Kurti, P.J. 2016. Identification of alleles conferring resistance to gray leaf spot in maize derived from its wild progenitor species teosinte (Zea mays ssp. parviglumis). Crop Science. 56:209-218.
Interpretive Summary: In this work we identified genes from corn’s wild progenitor, teosinte, that confer resistance to the disease gray leaf spot. We show that they function in corn to confer high levels of disease resistance. This is the first time useful genes for disease resistance have been identified from teosinte.
Technical Abstract: Gray Leaf Spot [(GLS), causal agent Cercospora zeae-maydis and Cercospora zeina] is an important maize disease in the United States. Current control methods for GLS include using resistant cultivars, crop rotation, chemical applications, and conventional tillage to reduce inoculum levels. Teosinte (Zea mays ssp. parviglumis) is the wild progenitor of maize and easily forms hybrids with current maize inbreds. The aims of this study were to identify alleles from teosinte that, when introduced into temperate maize germplasm, conferred significant levels of GLS resistance. A population of 693 BC4S2 near isogenic lines (NILs), developed by crossing nine different teosinte accessions into the background of the maize inbred B73, were evaluated for GLS resistance in replicated field trials over two years. Six markers significantly associated with GLS resistance were identified using 768 single nucleotide polymorphism (SNP) markers that were used to genotype this population. Twenty-seven individual NILs that differed significantly from B73 for GLS resistance and that carried teosinte introgressions at the significantly-associated SNPs at bins 2.04, 3.06, 4.07, 5.03, 8.06, and 9.03, were selected for follow-up studies. F2:3 populations were developed by crossing each selected NIL to B73 followed by self-pollinating the progeny twice. These F2:3 populations were evaluated for GLS resistance and genotyped at the loci of interest. In most cases single marker analysis validated predicted allelic substitution effects from the original NIL populations.