Phenological response and photosynthetic capacity: Canola Phytotron Study

Abstract

This dataset contains phenological, physiological, and photosynthetic measurements from controlled-environment phytotron experiments conducted at Stellenbosch University between 2023 and 2025. The experiments assessed the responses of six <i>Brassica napus</i> (canola) cultivars differing in herbicide tolerance type (Conventional, Clearfield, Triazine-tolerant) and growing-season length (Early, Medium) under three climate scenarios representative of Mediterranean-type conditions: (1) CTPC – current temperature with pre-industrial CO₂; (2) ETPC – elevated temperature with pre-industrial CO₂; and (3) ETEC – elevated temperature with elevated CO₂.The dataset includes:<br>• Phenological timing (days to bud formation, first flower, first pod).<br>• Thermal time metrics (growing degree days and photothermal units).<br>• Steady-state gas-exchange traits measured with a LI-6400XT (net CO₂ assimilation A, stomatal conductance gsw, transpiration E, intrinsic water-use efficiency iWUE).<br>• A/Ci response-curve data used to derive Farquhar–von Caemmerer–Berry model parameters (Vcmax, Jmax, TPU, Jmax/Vcmax).<br>The dataset supports a mechanistic evaluation of how warming and CO₂ enrichment independently and interactively affect developmental progression, electron transport capacity, carbon assimilation, stomatal behaviour, and sink limitation in canola. These data underpin the associated research article, which investigates cultivar-specific physiological strategies contributing to adaptation under projected climate conditions in Mediterranean-type regions.