Persistent and transient QTLs underlying growth trajectory of plant height in sorghum

Authors: ALLADASSI, BORIS - Iowa State University; MU, QI - Iowa State University; WEI, JIALU - Iowa State University; MIGUEZ, FERNANDO - Iowa State University; PRICE, KEVIN - Tmi Solutions Llc - Total Midstream Integration Solutions Llc; Li, Xianran; YU, JIANMING - Iowa State University

Submitted to: Journal of Experimental Botany
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/19/2026
Publication Date: 3/25/2026
Citation: Alladassi, B.M., Mu, Q., Wei, J., Miguez, F.E., Price, K., Li, X., Yu, J. 2026. Persistent and transient QTLs underlying growth trajectory of plant height in sorghum. Journal of Experimental Botany. p.1-12. https://doi.org/10.1093/jxb/erag062.
DOI: https://doi.org/10.1093/jxb/erag062

Interpretive Summary: Plant height matters to farmers and depends on genes and the environment plants growing. Because of the low throughput manual measurement, typically only the final terminal plant height was measured for a a large genetic population. High throughput phenotyping platform, such as Unmanned Aerial Vehicle (UAV), open the possibility to phenotype plant height multiple times to track the growing pattern over the entire season. This study reported findings from modeling plant height developed across a sorghum mapping population. Two types of gene actions were detected. One type is persistent QTLs that have significant effect along the whole growing season. The second is transient QTLs that have signficant effect on plant height during certain stages. Combining drones and genetics, we better understand how genes control plant height, which could improve crops.

Technical Abstract: Plant height is a critical agronomic trait controlled by multiple interacting genetic and environmental factors throughout development. Genetics studies based on the final plant height measurement focus only on the outcome of a complex and dynamic process. Uncovering the genetic basis underlying the temporal dynamics of plant height will enhance our understanding of the genotype-to-phenotype relationship. Here, we used time-series data extracted from UAV-based RGB imagery and functional mapping to investigate the temporal dynamics of plant height in two sorghum populations. First, we compared the UAV-derived measurements with manual measurements, and there were significant correlations of up to 0.94, indicating the 3D reconstruction of the field successfully captured the differences in the genotypes’ height. Next, we modeled the growth trajectory of each genotype using a logistic function, and treating the model parameters of the genotypes as derived traits, we detected strong signals of QTLs, co-localizing with Dw1, Dw2, Dw3, and qHT7.1, controlling the variation in the overall growth trajectories of the genotypes. Finally, to visualize the temporal dynamics of the plant height QTLs, we used the logistic function to estimate each genotype’s height and growth rate at a five-day interval from 20-110 days after planting (DAP). Genome scans of the model-estimated heights detected QTLs with dynamic effects across development. Persistent QTLs, co-localizing with Dw1, Dw2, Dw3, and qHT7.1, were detected from 40-110 DAP, whereas several transient QTLs were detected during specific, shorter periods. The insights gained from this study enabled us to create a revised conceptual figure, depicting six dynamic patterns of persistent and transient QTLs effects in determining the growth trajectories of sorghum genotypes. Overall, this study demonstrates the potential of employing an integrative approach to dissect the genetic basis of complex traits and gain new biological insights into the genetics of an important developmental feature such as ontogeny in plants.