Abstract: Nocturnal stomatal conductance (g_sn) represents a significant, enigmatic source of water-loss, with implications for whole plant metabolism, thermal regulation and water-use efficiency. With night-time temperatures rising at a rate 1.4x that of daytime temperatures, it is vital to identify and understand variation in the magnitude and responses of g_sn in major crops such as wheat. Using a custom temperature free-air controlled enhancement (T-FACE) setup in North-Western Mexico, the nocturnal field responses of twelve T. aestivum genotypes were investigated in response to artificial nighttime warming.

The magnitude of g_sn was genotype-and growth-stage-specific, accounting for up to 19% of daytime rates of water loss. Finally, we explore the variation in g_sn and its potential links with foliar uptake, cuticular conductance and establishment under nocturnal heat.

Biography: Dr Lorna McAusland is a plant physiologist (pronouns she/her), specialising in the dynamic responses of photosynthesis and water regulation to heat stress. Currently hosted by Professor Erik Murchie’s lab at the University of Nottingham (UK), Lorna was recently awarded a BBSRC-Discovery Fellowship; working on development of high-throughput systems to assess non-foliar photosynthesis under heat.