Crop photoperiodism model 2.0 for the flowering time of sorghum and rice that includes daily changes in sunrise and sunset times and temperature acclimation

Area of Science:

• Plant science
• Chronobiology
• Agricultural science

Background:

• Daylength is a primary determinant of plant flowering dates.
• Environmental factors influencing flowering synchronization across latitudes remain incompletely understood.
• Daily changes in sunrise and sunset times cue biological events, including plant flowering and circadian clock synchronization.

Purpose of the Study:

• To update the photoperiodism model with recent scientific insights.
• To investigate the role of daily sunrise and sunset changes in regulating plant flowering.
• To improve the accuracy of flowering time predictions in diverse geographical locations.

Main Methods:

• Collected extensive datasets on sorghum and rice flowering times across multiple tropical and temperate locations.
• Implemented an additive linear model incorporating daylength and daily changes in sunrise and sunset times.
• Validated the model's predictive accuracy using field data from various latitudes.

Main Results:

• Developed a unique additive linear model for predicting duration to panicle initiation (PI) and flowering time.
• The model accurately predicted PI duration across latitudes without requiring temperature inputs.
• Model calibration on tropical data enabled accurate predictions from equatorial to temperate zones.

Conclusions:

• The updated photoperiodism model, including daily sunrise and sunset changes, significantly improved prediction accuracy.
• Further research is recommended to confirm multi-latitudinal accuracy, particularly near the equator.
• This enhanced model offers a more precise tool for understanding and predicting plant flowering responses.