Three positive clones were selected for further study. The clones appear closely homologous to each other and to the Arabidopsis Agamous gene. When using the 3' half of each clone, gene- specific bands are detected on cucumber genomic blots, in addition to some bands that are shared by the other clones. Organ-specific patterns of expression in male and female cucumber flowers were observed by Northern analysis, and differed between the clones. Attempts to clone other sex-specific genes by other approaches, such as differential display, are under way in our laboratory.
Molecular markers have potential for increasing the efficiency of breeding programs.
Genetic maps exist which possess valuable genetic information. However, their value is limited because, individually, they do not provide enough information for effective use in a cucumber improvement program. If the information on all maps could be merged into a unified map, then the potential utility of the linked markers would be dramatically increased. QTL analysis revealed genomic regions associated with important yield and quality traits. Nevertheless, the USDA-CIP has identified 70 RFLP and 80 RAPD markers in two plant populations and has determined their spatial arrangement by constructing two genetic maps.