Phylogenetic Relationship ofEchinochloaSpecies Based on Simple Sequence Repeat and Phenotypic Marker Analyses

Abstract

Echinochloaspecies are among the most troublesome weeds in rice cultivation, and grow in a broad habitat range in Korea. Although various ecotypes ofEchinochloahave been collected as germplasm for future studies, it has been difficult to classify them due to their high level of morphological similarity. This study was thus conducted to develop and investigate the phylogenetic relationships between 77Echinochloaaccessions with the use of 23 simple sequence repeat (SSR) markers and 24 morphological traits. Of 77Echinochloaaccessions, including 57 accessions from Korea and 5 reference species, late watergrass was clearly clustered as a distinctive group from barnyardgrass and otherEchinochloaspecies. In this analysis, we also identified core genetic and morphological markers that can be used for the future identification and classification ofEchinochloaspecies. Five out of 23 SSR makers produced distinctive bands that discriminate late watergrass from barnyardgrass and otherEchinochloaspecies. Four morphological traits of the reproductive organs were the most influential contributors for classifyingEchinochloaspecies. Although there was no clear consensus generated in this study between SSR markers and morphological trait analyses, our results support the potential use of the selected SSR markers and morphological traits in future studies ofEchinochloa.