Abstract Detail

Crops and Wild Relatives

Nolting, Kristen [1], Dittmar, Emily [1], Donovan, Lisa [2], Burke, John [3].

Do crops have reduced stress tolerance compared with their wild progenitors? Evidence from a comprehensive meta-analysis.

A common assumption is that cultivated species are less stress tolerant when compared to their wild progenitors as a result of the domestication process. Stress tolerance is thought to be lost during domestication due to a reduction in genetic diversity and/or trade-offs with traits of agronomic importance. There remains little empirical evidence, however, to support this expectation of reduced tolerance. We conducted a semi-systematic literature review and meta-analysis to evaluate the existing evidence for reduced stress tolerance in a myriad of different crop taxa and stress types. Our search yielded ~1900 papers out of which, only 42 had appropriate data for inclusion in the final meta-analysis (i.e. included mean performance for a crop species and its wild progenitor in control and stress conditions, with appropriate measures of variance). Overall, we find that wild progenitors are slightly less negatively affected by stress compared with cultivated species, but the magnitude of this difference is small relative to the unexplained variation in the stress response across studies. We have some evidence that the type of stress implemented (e.g. nutrient versus drought stress) and the type of trait used to quantify tolerance (e.g. vegetative traits versus reproductive traits) may explain some of the variation in the stress effect across studies.
While we observe that the difference in the stress effect between cultivated species and their wild progenitors is small on average, it is striking that in all studies included in our meta-analysis we detect a more negative effect of stress on the cultivated species compared with the wild progenitor (even if this effect is not significant within that study). The consistency of this domestication effect across studies highlights the value of a meta-analysis, which gives us the ability to evaluate the repeatability of the domestication effect across studies, taxa, stress types, etc. However, within any given study our results suggest that it will be difficult to detect a significant domestication effect, given the degree of variation in the stress effect overall.

1 - University of Georgia, 2502 Miller Plant Sciences, Athens, GA, 30602, United States
2 - University Of Georgia, DEPT PLANT BIOLOGY , 2052 Miller Plant Sciences, Athens, GA, 30602, United States
3 - University Of Georgia, Dept Of Plant Biology, Miller Plant Sciences, Athens, GA, 30602, United States

Abiotic stress
wild progenitor

Presentation Type: Oral Paper
Number: CWR1011
Abstract ID:784
Candidate for Awards:None

Copyright © 2000-2022, Botanical Society of America. All rights reserved