Development and characterization of microsatellite markers for Sagittaria trifolia var. sinensis (Alismataceae).

PREMISE OF THE STUDY: Microsatellite markers were developed for the aquatic plant Sagittaria trifolia var. sinensis to assess its genetic diversity and population structure. Cross-species transferability was assayed in eight congeneric species. METHODS AND RESULTS: Seventeen microsatellite markers were isolated and characterized in Sagittaria trifolia var. sinensis using Fast Isolation by AFLP of Sequence COntaining Repeats (FIASCO) protocol. Across the evaluated populations, 14 of the markers showed polymorphisms with 3 to 11 alleles per locus; the observed and expected heterozygosity (H(o) and H(E)) ranged from 0.0000 to 0.6364 and from 0.0000 to 0.8386, respectively. Nine of the loci were successfully amplified in the congeneric species. CONCLUSIONS: These markers will be useful for further investigation of population genetics in Sagittaria trifolia var. sinensis and related research in Sagittaria species.

Characterization of 11 new microsatellite loci in taro (Colocasia esculenta).

Eleven new microsatellite markers were isolated from taro, Colocasia esculenta (L.) Schott, a root crop widely distributed all over the world. Forty-eight primer pairs were designed from a microsatellite-enriched genomic library, of which 11 primer pairs have polymorphisms in 30 individuals tested from a population in China, which revealed two to six alleles per locus with the observed and expected heterozygosity levels ranging from 0 to 0.733 and from 0.381 to 0.731, respectively. These new genetic markers will be useful for the study of taro germplasm management and population evolution in the future.

A preliminary study on population genetic structure and phylogeography of the wild and cultivated Zizania latifolia (Poaceae) based on Adh1a sequences.

Recent decades have witnessed growing interests in exploring the population genetics and phylogeography of crop plants and their wild relatives because of their important value as genetic resources. In this study, sequence variation of the nuclear Adh1a gene was used to investigate the genetic diversity and phylogeographic pattern of the wild and cultivated Zizania latifolia Turcz. Sequence data were obtained from 126 individuals representing 21 wild populations in China and 65 varieties of the cultivated Zizania latifolia. Low to medium level nucleotide diversity was found in the wild populations, with northeastern populations being the most variable. We detected significant population subdivision (F (ST) = 0.481) but no significant phylogeogaphical structure, suggesting limited gene flow and dispersal among populations. The current pattern of genetic variation in the wild populations might be explained by a fragmentation of ancient populations due to habitat destruction and degradation during recent decades. The heterogeneous levels and spatial apportionment of genetic diversity among wild populations also suggested a history of gradual colonization of Zizania latifolia populations from the northeast to the south of China. Interestingly, all 65 varieties of the cultivated Zizania latifolia possessed a single identical genotype, implying a single domestication associated with very few initial individuals.