Abstract Detail

Molecular Ecology and Evolution

Meyer, Rachel [1], Whitaker, Bruce [2], Little, Damon [3], Litt, Amy [4].

Molecular and chemical differences among Asian eggplants analyzed in a framework of their history of utilization.

Eggplants (Solanum melongena L.) were domesticated in tropical Asia where they are commonly used as both food and medicine. Human selection has produced hundreds of landraces with differences in morphology and in chemistry that may be related to ethnobotanical preferences in certain locales. Here we synthesize the results of a multi-disciplinary project that explored the genetic, phytochemical, and ethnobotanical diversity of Asian eggplant landraces and wild relatives. The aim of the project was to use Solanum species and eggplant landraces to identify differences in molecular function and chemistry that correlate with domestication events and possible selection pressures. Population genetic analyses using AFLP and molecular phylogeny revealed that eggplants appear to have been domesticated at least three times, in India, southern China, and the Indo-Malayan islands (Malesia). Phytochemical analyses of the abundance of 43 phenolic compounds using HPLC showed significantly different levels of hydroxycinnamic acid polyamine amides (HCAAs) among putative independently domesticated lineages. These HCAAs are thought to contribute to the flavor, health-benefits, and even texture of eggplant fruit. qRT-PCR-based study of mRNA expression levels of 12 enzymes in the phenolic pathway revealed differences among lineages, notably in the expression of spermidine hydroxycinnamoyl transferases, which may underlie some of the differences in phytochemical profiles. Contemporary and historic ethnobotanical data on eggplant from India, China, and Malesia, gathered through semi-structured interviews and literature review, was compared to archaeobotanical and linguistic records of cultural interactions among these regions. Results led to new hypotheses on the date of eggplant domestication in Malesia, a region that lacks a historic record. Results also suggest that cultural preferences for mild flavor and soft fruit texture may explain the gene-regulatory and chemical differences among Asian landraces.

Broader Impacts:

1 - The New York Botanical Garden, 2900 Southern Blvd, Bronx, NY, 10458
2 - United States Department of Agriculture, Food Quality Laboratory, 10300 Baltimore Avenue, Bldg 2 BARC-West, Beltsville, MD, 20705, USA
3 - The New York Botanical Garden, Bronx, NY, 10458-5126, USA
4 - New York Botanical Garden, 200th St And Southern Blvd., Bronx, NY, 10458, USA

Keywords:
crop plants
wild relative
phenolic compounds
Phylogeography
artificial selection
Domestication
Solanaceae
Solanum
food
phenolic pathway.

Presentation Type: Oral Paper:Papers for Topics
Session: 16
Location: Union B/Hyatt
Date: Monday, July 9th, 2012
Time: 4:00 PM
Number: 16010
Abstract ID:920