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Title: Resistance to Gibberella ear rot in maize: Insights from near‐isogenic line populations
Abstract Gibberella ear rot (GER) of maize, caused byFusarium graminearum, poses a serious threat to human and animal safety as mycotoxins are deposited in the grain during fungal colonization and are hazardous to human and animal health. Currently, no completely resistant germplasm has been identified, and the underlying mechanisms of resistance remain unclear. In this study, we evaluated three near‐isogenic line (NIL) populations for resistance to GER—NC344 × H100 (DRIL), B73 × Oh43 (nNIL), and B73 × teosinte (tNIL)—across multiple environments. The recurrent parents, H100 and B73, were moderately resistant to GER. NC344 is susceptible to GER. Oh43 is moderately resistant to GER. The teosinte donor parent, PI 384071, had unknown resistance to GER. We employed two inoculation methods—kernel injection and silk channel injection—to assess their impact on genotype response to F. graminearum. The inoculation method did not significantly affect genotype response, although kernel inoculations produced more consistent disease levels. We identified lines with significantly increased susceptibility to GER compared to their recurrent parent in each population. We employed quantitative trait locus (QTL) mapping to identify markers associated with GER in the NC344 × H100 population. We identified QTL on chromosomes 4, 5, and 9. We highlight a large region on chromosome 5 that may harbor important alleles for GER resistance and for resistance to other ear rots. This study underscores the utility of NILs in dissecting the genetic basis of GER resistance and provides valuable resources for future fine mapping, gene discovery, and resistance breeding.  more » « less
Award ID(s):
2154872
PAR ID:
10693875
Author(s) / Creator(s):
 ;  ;  ;  
Publisher / Repository:
Wiley Periodicals LLC on behalf of Crop Science Society of America
Date Published:
Journal Name:
Crop Science
Volume:
65
Issue:
6
ISSN:
0011-183X
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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