Abstract Detail

Darwins' reversals: What we now know about Feralization and Crop Wild Relatives

Razifard, Hamid [1], Ramos, Alexis [2], Tieman, Denise [3], van der Knaap, Esther [4], Caicedo, Ana [5].

Genomic Evidence for Complex Domestication History of the Cultivated Tomato in Latin America.

Plant domestication is often a complex process, involving under-explored intermediate stages with important implications for the evolutionary trajectories of domestication traits. Previously, tomato domestication history was thought to involve two major transitions: one from wild Solanum pimpinellifolium L. (SP) to a semi-domesticated intermediate, S. lycoperiscum L. var. cerasiforme (SLC), in South America, and a second transition from SLC to fully domesticated S. lycopersicum L. var. lycopersicum (SLL) in Mesoamerica. Using a dataset of 296 accessions obtained from de-novo whole-genome sequencing and from previously published data, we employ population genomic methods to reconstruct tomato domestication history, focusing on the evolutionary changes occurring in the intermediate stages. Our results suggest that SLC originated approximately 80 thousand years ago (KYA) predating earliest archeological records of plant domestication, suggesting that SLC may have diverged from SP as a wild population. Many traits considered typical of cultivated tomatoes arose in South American SLC, but were lost or diminished once these partially domesticated SLC spread northward to Mesoamerica, likely due to increased ferality or adaptation to new environments. Several traits were reselected in a convergent fashion in SLL, the common cultivated tomato, probably around 7 KYA, prior to its expansion around the world. Based on these findings, we reveal complexities in the intermediate stage of tomato domestication and provide insight on trajectories of important genes and phenotypes involved in the tomato domestication syndrome. Our results also allow us to identify underexplored germplasm that harbors useful alleles for crop improvement.

1 - Cornell University, 819 Ringwood Road, Apt. 3, Ithaca, New York, 14850, United States
2 - University of Georgia, Department of Horticulture, , Athens, GA 30602, USA
3 - University of Floida, Horticultural Sciences, Plant Innovation Center, Gainesville, FL 32611, USA
4 - University of Georgia, Department of Horticulture, Athens, GA 30602, USA
5 - University of Massachusetts Amherst, Institute for Applied Life Sciences, Amherst, MA 01003, USA

Keywords:
tomato
domestication
feralization
genomics
populationg genetics.

Presentation Type: Colloquium Presentations
Session: C03, Darwins' reversals: What we now know about Feralization and Crop Wild Relatives
Location: /
Date: Tuesday, July 20th, 2021
Time: 12:30 PM(EDT)
Number: C03010
Abstract ID:100
Candidate for Awards:Margaret Menzel Award