Submitted to: Maydica
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/1/1997
Publication Date: N/A
Citation: Interpretive Summary: The transfer of apomixis (asexual reproduction through the seed) from eastern gamagrass to corn would allow the production of true breeding hybrid corn at reduced costs for the seed producer and the grower. DNA from triploid eastern gamagrass populations segregating for sexual and asexual modes of reproduction were analyzed by RFLP to determine which markers were associated with the apomictic trait. Five markers were found to co-segregate with seed set fertility regulated by apomixis. They will be useful for detecting and isolating the genes responsible for the apomictic trait.
Technical Abstract: Genetically related triploid populations of Tripsacum dactyloides segregating for sterility were shown to co-segregate with particular RFLP markers. While the percentage of seed set varies within apomictic populations, it is known that sterility, the absence of seed, is associated with sexual reproduction in triploid populations. Given this, it is of interest that five out of 25 RFLP markers showed co-segregation with the phenotype, percent seed set, scored on 86 individuals. This subset of markers are known to be linked to the Tripsacum linkage groups A, F, H, I and L and are syntenic in maize to chromosome 1, 7 and 6. It is significant that the five Tripsacum linkage groups discussed here have syntenic regions in maize. Specifically, these maize regions harbor genes regulating male sterility, defective kernel development, and gametophyte and fertility associated genes.