Assessing Genetic Diversity and Population Differentiation of Colored Calla Lily (Zantedeschia Hybrid) for an Efficient Breeding Program.

Plastome-genome incompatibility (PGI) is prevalent in several plants including the species, a worldwide commercial flower crop native to South Africa. Generally, hybrids suffering from PGI appear less vigorous and more susceptible than normal plants. Previous reports revealed that the PGI level in interspecific hybrids is correlated with the relatedness of the parental species in the genus . To provide a basis for utilizing and improving resources in breeding programs, a total of 117 accessions of colored calla lily ( hybrid), collected from New Zealand, the Netherlands and the United States, were genotyped using 31 transferable expressed sequence tags-simple sequence repeats (EST-SSR) markers from the white calla lily (). A moderately high level of genetic diversity was observed, with 111 alleles in total, an observed/expected heterozygosity () of 0.453/0.478, and polymorphism information content () of 0.26. Genetic distance and STRUCTURE-based analysis further clustered all accessions into four subgroups (G-Ia, G-Ib, G-IIa and G-IIb), which mostly consisted of , and , respectively. Significant genetic differentiation was observed between all inferred subgroup pairs, with the ranging from 0.142 to 0.281. Finally, the accessions assigned into G-IIb () were recommended as top priority parents in efficient breeding program designs.