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bioRxiv · 10.1101/2025.09.08.674796

Multi-omics profiling with indoor-unmanned phenotyping reveals drought adaptation through constitutive ABF1 expression in wild rice

Abstract

Improving drought resistance is crucial for stable crop production under climate change. Identifying the mechanisms of drought resistance using diverse genetic resources, including crop wild relatives, would be beneficial for molecular breeding. Here, we developed an indoor, unmanned phenotyping platform that can noninvasively and automatically collect temporal data on plant responses to drought stress. Using this system, we analyzed the phenotypic, transcriptomic, and environmental data of four cultivated rice varieties and five wild relatives. Multi-omics analysis revealed that one wild rice species exhibited drought adaptation through the constitutive expression of ABSCISIC ACID RESPONSIVE ELEMENT-BINDING FACTOR 1 (ABF1), which encodes a transcription factor that regulates drought resistance, before drought stress. Drought testing of introgression lines of cultivated rice with constitutive ABF1 expression revealed higher drought tolerance than in cultivars without a growth penalty. Our findings suggest that constitutive ABF1 expression contributes to drought adaptation in both cultivated and wild rice.

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Soma, F., Kawahara, Y., Tanabata, T., Hayashi, A., Kitomi, Y., Kochi, N., Yamamoto, E., Tanaka, N., Negishi, M., Tokuda, K., Sakai, H., Uga, Y.. 2025-09-12. Multi-omics profiling with indoor-unmanned phenotyping reveals drought adaptation through constitutive ABF1 expression in wild rice. https://doi.org/10.1101/2025.09.08.674796

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