Author
VARELLA, A - Montana State University | |
WEAVER, D - Montana State University | |
SHERMAN, J - Montana State University | |
BLAKE, N - Montana State University | |
HEO, H - Montana State University | |
KALOUS, J - Montana State University | |
Chao, Shiaoman | |
HOFLAND, M - Montana State University | |
MARTIN, J - Montana State University | |
KEPHART, K - Montana State University | |
TALBERT, L - Montana State University |
Submitted to: Crop Science
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 3/14/2015 Publication Date: 9/1/2015 Publication URL: http://handle.nal.usda.gov/10113/62699 Citation: Varella, A.C., Weaver, D.K., Sherman, J.D., Blake, N.K., Heo, H.Y., Kalous, J.R., Chao, S., Hofland, M.L., Martin, J.M., Kephart, K.D., Talbert, L.E. 2015. Association analysis of stem solidness and wheat stem sawfly resistance in a panel of North American spring wheat germplasm. Crop Science. 55:2046-2055. Interpretive Summary: Expansion of the geographical range of the wheat stem sawfly, coupled with the limited number of effective control measures, calls for a need to better characterize and explore genetic variability for resistance in wheat germplasm from North America. A genetic mapping analysis for stem solidness and wheat stem sawfly resistance was conducted using a set of 244 elite lines of spring wheat from ten North American breeding programs. DNA markers associated with both early and late stem solidness were identified and agreed with some of the previously reported observations. Potential sources of a novel resistance mechanism causing larval mortality were also identified. Results indicated that favorable alleles for stem solidness and other resistance traits are available within North American wheat germplasm, but only Montana and South Dakota breeding programs appear to have favorable alleles for all the genes associated with these traits detected in this study. Thus, improvements in wheat stem sawfly management for both historically impacted areas and newly infested regions can be obtained through collaborative efforts between breeding programs. Technical Abstract: Expansion of the geographical range of the wheat stem sawfly, coupled with the limited number of effective control measures, calls for a need to better characterize and explore genetic variability for resistance in wheat germplasm from North America. An association mapping analysis for stem solidness and wheat stem sawfly resistance was conducted using a set of 244 elite lines of spring wheat from ten North American breeding programs. Three previously identified quantitative trait loci (QTL) for resistance were confirmed, including QTL for stem solidness, heading date, and stem cutting. Three new QTL on chromosomes 2A, 3A, and 5B were identified to be associated with larval mortality. A QTL associated with the early stem solidness was identified on chromosome 5D. Genetic variation for late stem solidness is mainly determined by the solid stem QTL on chromosome 3B, while variation for early solidness is affected by chromosomal regions on 1B, 3B, and 5D. Potential sources of a novel resistance mechanism causing larval mortality were identified among the panel lines. Favorable alleles for stem solidness and other resistance traits are available within North American wheat germplasm, but only Montana and South Dakota breeding programs appear to have favorable alleles for all QTLs detected in this study. Thus, improvements in wheat stem sawfly management for both historically impacted areas and newly infested regions can be obtained through collaborative efforts between breeding programs. |