High throughput screen of NPQ in sorghum shows highly polygenic architecture of photoprotection

Vath, R. L.; Fernandes, S.; Monier, B.; Glowacka, K.; Walter, J.; Lipka, A. E.; Ferguson, J. N.; Bernacchi, C.; Pederson, T.; Kromdijk, J.

doi:10.1101/2025.04.18.649521

bioRxiv · 10.1101/2025.04.18.649521

High throughput screen of NPQ in sorghum shows highly polygenic architecture of photoprotection

Vath, R. L.·Fernandes, S.·Monier, B.·Glowacka, K.·Walter, J.·Lipka, A. E.·Ferguson, J. N.·Bernacchi, C.·Pederson, T.·Kromdijk, J.

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Abstract

O_LINatural genetic variation in photosynthesis and photoprotection within crop germplasm represents an untapped resource for crop improvement. Sorghum bicolor (sorghum) is one of the worlds most widely grown crops, yet the genetic basis of photoprotection in sorghum is not well understood. C_LIO_LIThis study examined genetic variation in non-photochemical quenching traits by screening a field-grown panel of 861 genetically diverse natural sorghum accessions across two years. C_LIO_LIBroad-sense heritability ranged between 0.3 to 0.65 across different chlorophyll fluorescence parameters. A combination of genome- and transcriptome-wide (GWAS and TWAS) identification of genetic correlates with the observed trait variation uncovered a complex genetic architecture of many significant small-effect loci. An ensemble approach based on GWAS and TWAS results and the covariance between different fluorescence parameters was used to identify 110 unique candidate genes. C_LIO_LIThe resulting high-confidence candidates reveal novel genetic associations with photoprotection and offer resources for further genetic studies and crop genomic improvement efforts. C_LI

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Vath, R. L., Fernandes, S., Monier, B., Glowacka, K., Walter, J., Lipka, A. E., Ferguson, J. N., Bernacchi, C., Pederson, T., Kromdijk, J.. 2025-04-22. High throughput screen of NPQ in sorghum shows highly polygenic architecture of photoprotection. https://doi.org/10.1101/2025.04.18.649521

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