Abstract Detail

Genetics Section

Dane, Fenny [1], Lang, Ping [1], Liu, Rona [1].

Sequence variation at chloroplast and nuclear DNA regions of Citrullus species: implications for the evolution of watermelon.

Sequencing analysis of five chloroplast DNA regions and o­ne intron of glyceraldehyde 3- phosphate dehydrogenase were conducted to infer biogeographic and evolutionary relationships in the genus Citrullus. Eighteen taxa from diverse geographical areas were included. Variability within Citrullus was detected at noncoding cpDNA regions of high A+T content mainly. A similar number of parsimony informative sites were detected at the ~ 4 kb section of cpDNA and 0.6 kb of nuclear DNA. The genus Citrullus is supported monophyletically and shows two main clades, o­ne of which contains C. colocynthis, the bitter apple. In the other clade, C. ecirrhosus and C. lanatus group into a clade, which is sister to a clade containing C. rehmii. Haplotypes can be used to deduce colonization routes, and in C. colocynthis suggest separate colonization events from the Middle East into Africa and the Far East. Variability detected among the cultivated and wild watermelon will be used to trace the domestication events of cultivated watermelon.

1 - Auburn University, Horticulture, 101 Funchess Hall, Auburn, Alabama, 36849

Keywords:
Citrullus
chloroplast
biogeography
domestication
watermelon.

Presentation Type: Poster
Session: 32-47
Location: Special Event Center (Cliff Lodge)
Date: Tuesday, August 3rd, 2004
Time: 12:30 PM
Abstract ID:313