TY - JOUR
T1 - High congruency of QTL positions for heterosis of grain yield in three crosses of maize
AU - Schön, Chris C.
AU - Dhillon, Baldev S.
AU - Utz, Friedrich F.
AU - Melchinger, Albrecht E.
N1 - Funding Information:
We are grateful to R. Bernardo, C.W. Stuber, and Z.-B. Zeng for providing the raw data for Pop1 and Pop2 and to E. Frascaroli for providing heritability estimates for Pop3. We thank G. Haseneyer and D. Campell for their help with the linkage map comparisons, and an anonymous reviewer for suggestions. This research was financed by the Deutsche Forschungsgemeinschaft (DFG) within the priority program SPP 1149 “Heterosis in Plants” (Research Grant ME931/4-3).
PY - 2010/1
Y1 - 2010/1
N2 - The genetic basis of heterosis in maize has been investigated in a number of studies but results have not been conclusive. Here, we compare quantitative trait loci (QTL) mapping results for grain yield, grain moisture, and plant height from three populations derived from crosses of the heterotic pattern Iowa Stiff Stalk Synthetic × Lancaster Sure Crop, investigated with the Design III, and analyzed with advanced statistical methods specifically developed to examine the genetic basis of mid-parent heterosis (MPH). In two populations, QTL analyses were conducted with a joint fit of linear transformations Z1 (trait mean across pairs of backcross progenies) and Z2 (half the trait difference between pairs of backcross progenies) to estimate augmented additive and augmented dominance effects of each QTL, as well as their ratio. QTL results for the third population were obtained from the literature. For Z2 of grain yield, congruency of QTL positions was high across populations, and a large proportion of the genetic variance (~70%) was accounted for by QTL. This was not the case for Z1 or the other two traits. Further, almost all congruent grain yield QTL were located in the same or an adjacent bin encompassing the centromere. We conclude that different alleles have been fixed in each heterotic pool, which in combination with allele(s) from the opposite heterotic pool lead to high MPH for grain yield. Their positive interactions very likely form the base line for the superior performance of the heterotic pattern under study.
AB - The genetic basis of heterosis in maize has been investigated in a number of studies but results have not been conclusive. Here, we compare quantitative trait loci (QTL) mapping results for grain yield, grain moisture, and plant height from three populations derived from crosses of the heterotic pattern Iowa Stiff Stalk Synthetic × Lancaster Sure Crop, investigated with the Design III, and analyzed with advanced statistical methods specifically developed to examine the genetic basis of mid-parent heterosis (MPH). In two populations, QTL analyses were conducted with a joint fit of linear transformations Z1 (trait mean across pairs of backcross progenies) and Z2 (half the trait difference between pairs of backcross progenies) to estimate augmented additive and augmented dominance effects of each QTL, as well as their ratio. QTL results for the third population were obtained from the literature. For Z2 of grain yield, congruency of QTL positions was high across populations, and a large proportion of the genetic variance (~70%) was accounted for by QTL. This was not the case for Z1 or the other two traits. Further, almost all congruent grain yield QTL were located in the same or an adjacent bin encompassing the centromere. We conclude that different alleles have been fixed in each heterotic pool, which in combination with allele(s) from the opposite heterotic pool lead to high MPH for grain yield. Their positive interactions very likely form the base line for the superior performance of the heterotic pattern under study.
UR - http://www.scopus.com/inward/record.url?scp=75849127045&partnerID=8YFLogxK
U2 - 10.1007/s00122-009-1209-9
DO - 10.1007/s00122-009-1209-9
M3 - Article
C2 - 19911156
AN - SCOPUS:75849127045
SN - 0040-5752
VL - 120
SP - 321
EP - 332
JO - Theoretical and Applied Genetics
JF - Theoretical and Applied Genetics
IS - 2
ER -