Submitted to: Maydica
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/20/1996
Publication Date: N/A
Citation: Interpretive Summary: The primary objectives of the study reported in this manuscript were to: 1) identify genetic factors affecting agronomic traits such as grain yield, plant height, and days to flowering, and 2) to relate these genetic factors to the level of grain yield. The plant materials used for the study were derived from Croatian open-pollinated varieties of corn. Two genetic populations were generated from these varieties, and genetic factors for all three traits were identified in both populations. The results indicate that exotic materials, such as these varieties from Croatia, can be used as sources of new genetic variants for transfer into and improvment of domestic corn breeding populations.
Technical Abstract: The major objectives of this study included: 1) detect QTLs for grain yield (YLD), plant height (PH), and days to pollen shed (DPS) in maize exotic germplasm, and 2) to determine the relationship between the degree of heterozygosity of marker alleles and the level of yield. Lines selected from Croatian open-pollinated varieties were used to generate two half-sib populations for the study. In each population, 169 F3 families were tested in field experiments at two locations. The 20 highest and the 20 lowest yielding families of each population were used for QTL detection. Isozymes, RFLPs and Simple Sequence Repeats (SSRs) were used as molecular markers. Marker-trait associations were assessed by single factor and interval analyses. The population designated P1 had lower average yield but had more polymorphic loci and revealed more QTLs than the population designated P2. In the two populations, QTLs for YLD were found on chromosomes 1, 6, and 10; for PH on chromosomes 1, 3, 5, and 6; and for DPS on chromosomes 1, 3, 6, 8 and 9. The populations had no QTLs in common. Higher yielding subpopulations showed a higher degree of heterozygosity than the lower yielding subpopulations.