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Intraspecific diversity as a reservoir for heat-stress tolerance in sweet potato


Stable and sufficient food supplies are increasingly threatened by climatic variability, in particular extreme heat events. Intraspecific crop diversity may be an important biological resource to both understand and maintain crop resilience to extreme conditions. Here using data from a mass field experiment screening for heat tolerance in sweet potato (Ipomoea batatas), we identify 132 heat-tolerant cultivars and breeding lines (6.7%) out of 1,973 investigated. Sweet potato is the world’s fifth most important food crop, and mean conditions experienced by sweet potato by 2070 are predicted to be 1 to 6 °C warmer, negatively impacting most genotypes. We identify canopy temperature depression, chlorophyll content and storage root-flesh colour as predictors of heat tolerance and, therefore, as potential traits for breeding consideration. These results highlight the role of intraspecific biodiversity for the productivity and resilience of food and agricultural systems in the face of climate change.

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Fig. 1: World map of the 1973 sweet potato cultivars and breeding lines tested in the intentional exposure and control trial for HS tolerance.
Fig. 2: Impact of heat stress on the performance of 1,973 sweet potato cultivars and breeding lines.
Fig. 3: Random forest analysis of intrinsic and extrinsic predictors of root yield in 1,973 sweet potato cultivars and breeding lines.
Fig. 4: Predicted climate stress by 2070 to be experienced by 1,472 sweet potato cultivars and breeding lines showing different levels of HS tolerance.

Data availability

A full description of sweet potato varieties is provided in Supplementary Table 1. Agronomic, morphological and climate data are available at Other data are available at Source data are provided with this paper.

Code availability

The analytical scripts are available using this:


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This research was undertaken as part of, and funded by, the CGIAR Research Program on Roots, Tubers and Bananas (RTB) and supported by CGIAR Fund Donors. We thank all donors who supported this research through their contributions to the CGIAR Fund: The financial support by the McKnight Foundation to Q.S. is greatly appreciated. We thank V. Vadez, IRD Montpellier, for his comments on a previous version of the manuscript.

Author information




B.H. designed the research; B.H., R.E., J.E.P., C.F. and E.F. performed research and collected data; B.H., R.E., Q.S., E.F. and O.D. analysed data; O.D. led the writing with contributions from B.H., Q.S., R.E. and S.d.H.

Corresponding authors

Correspondence to Bettina Heider or Olivier Dangles.

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Competing interests

The authors declare no competing interests.

Additional information

Peer review information Nature Climate Change thanks Samuel Pironon, Delphine Renard and the other, anonymous, reviewer(s) for their contribution to the peer review of this work.

Publisher’s note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Extended data

Extended Data Fig. 1 Geographic origin of 132 heat resistant cultivars of sweetpotatoes.

The total number of cultivars is given for each country, classified by continent. B. Compared proportions of each continent of origin between all cultivars and heat tolerant cultivars. Source data

Extended Data Fig. 2 Root yield under heat stress conditions of 1973 sweetpotato cultivars.

The cultivars were grouped according to their flesh color: orange (including dark orange, intermediate orange and pale orange), cream (including dark cream and cream) and yellow (including dark yellow and pale yellow). P-values refer to a Wilcoxon test. Strongly pigmented cultivars with anthocyanins were discarded due to their low occurrence in the data set. All root yields are expressed on a log scale. Source data

Supplementary information

Supplementary Information

Supplementary Tables 2–4 and Figs. 1–5.

Reporting Summary

Supplementary Table

List of the 1,973 sweet potato accessions.

Source data

Source Data Fig. 1

Source numerical data.

Source Data Fig. 2

Source numerical data.

Source Data Fig. 3

Source numerical data.

Source Data Fig. 4

Source numerical data.

Source Data Extended Data Fig. 1

Source numerical data.

Source Data Extended Data Fig. 2

Source numerical data.

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Heider, B., Struelens, Q., Faye, É. et al. Intraspecific diversity as a reservoir for heat-stress tolerance in sweet potato. Nat. Clim. Chang. 11, 64–69 (2021).

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