Seed fates in crop–wild hybrid sunflower: crop allele and maternal effects

Evolutionary Applications

Brian A. Pace²  Helen M. Alexander¹  Jason D. Emry³ 

[1] Department of Ecology and Evolutionary Biology, University of Kansas, Lawrence, KS, USA;Department of Horticulture and Crop Science, Ohio State University, Columbus, OH, USA;Department of Biology, Washburn University, Topeka, KS, USA

关键词: dormancy;    gene flow;    hybridization;    introgression;    maternal effects;    seed banks;    sunflower;   

DOI  :  10.1111/eva.12236

来源: Wiley

【 摘 要 】

Abstract

Domestication has resulted in selection upon seed traits found in wild populations, yet crop-wild hybrids retain some aspects of both parental phenotypes. Seed fates of germination, dormancy, and mortality can influence the success of crop allele introgression in crop-wild hybrid zones, especially if crop alleles or crop-imparted seed coverings result in out-of-season germination. We performed a seed burial experiment using crop, wild, and diverse hybrid sunflower (Helianthus annuus) cross types to test how a cross type's maternal parent and nuclear genetic composition might affect its fate under field conditions. We observed higher maladaptive fall germination in the crop- and F₁- produced seeds than wild-produced seeds and, due to an interaction with percent crop alleles, fall germination was higher for cross types with more crop-like nuclear genetics. By spring, crop-produced cross types had the highest overwintering mortality, primarily due to higher fall germination. Early spring germination was identical across maternal types, but germination continued for F₁-produced seeds. In conclusion, the more wild-like the maternal parent or the less proportion of the cross type's genome contributed by the crop, the greater likelihood a seed will remain ungerminated than die. Wild-like dormancy may facilitate introgression through future recruitment from the soil seed bank.

【 授权许可】

CC BY   
© 2014 The Authors. Evolutionary Applications published by John Wiley & Sons Ltd.

Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.