TITLE:
A Survey of Genetic Diversity of the Weedy Species Ipomoea lacunosa L. in the USA Mid-South
AUTHORS:
Nilda R. Burgos, Daniel O. Stephenson, Hesham A. Agrama, Lawrence R. Oliver, Jason A. Bond
KEYWORDS:
DNA Fingerprinting, Genetic Diversity, Ipomoea, ISSR, Morningglory Species, Morningglory Genotypes, Population Structure
JOURNAL NAME:
American Journal of Plant Sciences,
Vol.2 No.3,
September
30,
2011
ABSTRACT: Morningglories (Ipomoea spp.) are among the most troublesome weedy species in agroecological environments. Ipomoea lacunosa is one of the most prevalent of these species. Localized adaptations resulted in the evolution of several I. lacunosa ecotypes in North America, which could potentially impact its response to crop management practices. To evaluate the genetic diversity and population structure of I. lacunosa populations, we amplified inter-simple sequence repeats loci by polymerase chain reaction (ISSR-PCR) of 64 accessions using 14 ISSR primers for Ipomoea. Of these, 64 polymorphic fragments were scored. Analysis of Nei’s genetic distance (GD) values placed the accessions into four genotypic clusters, two of which were composed primarily of accessions from Arkansas and Mississippi with GD between clusters of 0.318. The overall GD was 0.238, indicating a narrow genetic base. Population structure analysis determined three ancestral subgroups, with the majority of Arkansas and Mississippi accessions separated into two subgroups. The existence of various genotypes and ecotypes of I. lacunosa demonstrates the evolutionary diversification of this weedy species as it adapts to new colonized environments and agricultural activities.