Genetic changes decreased maize’s tolerance to severe heat stress and increased resilience to moderate heat stress

The ability of crops to withstand heat is critical to our food system’s resilience to climate change. A study published in the open access journal PLOS genetics by Aaron Kusmec at Iowa State University; Ames, Iowa, USA, and colleagues suggest that trait selection through plant breeding increased maize tolerance to moderate heat stress over time; however, his tolerance to severe heat stress has decreased.

Corn is vulnerable to heat stress and high temperatures can decrease yields. However, the genetic adaptation of corn to heat over time is not well understood. To better understand how the heat tolerance of corn has changed over time, the researchers compiled 81 years of public performance trials records, including 4,730 corn hybrids. They matched corn yield data with historical weather records from the same time period. Using this data, they built a model that estimates genetic variation for temperature responses among corn hybrids.

The researchers found that corn’s tolerance to moderate heat stress increased, but tolerance to severe heat stress decreased. The study was limited by potential confounding factors such as environmental conditions other than temperature and precipitation. Future studies are needed to better understand the potential for plant breeders to select for temperature adaptation.

According to the authors, “Because climate change is notably expected to increase the incidence of severe heat stress, these findings indicate a need for more detailed genetic and physiological studies of heat tolerance and their incorporation into plant breeding efforts. plant. They also highlight plant breeders’ past successes in adapting corn to moderate heat stress.”

The authors add, “Using more than 80 years of archived hard-copy corn yield data from research libraries, we found that plant breeders increased hybrid corn’s tolerance to moderate heat stress, while inadvertently reducing its tolerance to severe heat stress. Unfortunately, the frequency of severe heat stress is expected to increase due to climate change.”

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In your coverage, use this URL to provide access to the article available for free at PLOS genetics:

http://journals.plos.org/plosgenetics/article?id=10.1371/journal.pgen.1010799

Citation: Kusmec A, Attigala L, Dai X, Srinivasan S, Yeh CT“, Schnable PS (2023) A genetic compromise for moderate and severe heat stress tolerance in US hybrid corn. PLoS Genet 19(7): e1010799. https://doi.org/10.1371/journal.pgen.1010799

Countries author: United States

Financing: This research was supported by the following grants awarded to PSS: Advanced Research Projects Agency-Energy (ARPA-E) grant No. DEAR0000826 (https://arpa-e.energy.gov/), USDA Agriculture and Food Research Initiative (AFRI ) concession no. 2017-67007-26175 and 2017-67013-26463, and concession no. USDA National Institute of Food and Agriculture (NIFA) No. 2012-67009-19713 (https://www.nifa.usda.gov/). This research was also supported by a National Science Foundation (NSF) grant No. DMS 2113713 (https://www.nsf.gov/) to XD. AK’s salary was partially supported by USDA AFRI grant 2017-67007-26175. XD’s salary was partially supported by NSF Grant No. DMS 2113713. SS’s salary was partially supported by USDA NIFA Grant No. 2012-67009-19713. C-TY’s salary was partially supported by ARPA-E grant no. DEAR0000826, from USDA NIFA Grant No. 2012-67009-19713 and USDA AFRI grant no. PSS’s salary was partially supported by the ARPA-E subsidy n. DEAR0000826 and USDA NIFA Grant No. 2012-67009-19713. Funders had no role in study design, data collection and analysis, decision to publish, or manuscript preparation.