RT Journal Article
SR Electronic
T1 Wheat photosystem II heat tolerance responds dynamically to short and long-term warming
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 2021.11.01.466822
DO 10.1101/2021.11.01.466822
A1 Posch, Bradley C.
A1 Hammer, Julia
A1 Atkin, Owen K.
A1 Bramley, Helen
A1 Ruan, Yong-Ling
A1 Trethowan, Richard
A1 Coast, Onoriode
YR 2021
UL http://biorxiv.org/content/early/2021/11/04/2021.11.01.466822.abstract
AB Heat-induced inhibition of photosynthesis is a key factor in declining wheat performance and yield. Variation in wheat heat tolerance can be characterised using the critical temperature (Tcrit) above which incipient damage to the photosynthetic machinery occurs. We investigated intraspecies variation and plasticity of wheat Tcrit under elevated temperature in field and controlled environment experiments. We also assessed whether intraspecies variation in wheat Tcrit mirrors patterns of global interspecies variation in heat tolerance reported for mostly wild, woody plants. In the field, wheat Tcrit varied through the course of a day, peaking at noon and lowest at sunrise, and increased as plants developed from heading to anthesis and grain filling. Under controlled temperature conditions, heat stress (36°C) was associated with a rapid rise in wheat Tcrit (i.e. within two hours of heat stress) that peaked after 3–4 days. These peaks in Tcrit indicate a physiological limitation to photosystem II heat tolerance. Analysis of a global dataset (comprising 183 Triticum and wild wheat (Aegilops) species) generated from the current study and a systematic literature review showed that wheat leaf Tcrit varied by up to 20°C (about two-thirds of reported global plant interspecies variation). However, unlike global patterns of interspecies Tcrit variation which has been linked to latitude of genotype origin, intraspecific variation in wheat Tcrit was unrelated to that. Yet, the observed genotypic variation and plasticity of wheat Tcrit suggests that this trait could be a useful tool for high-throughput phenotyping of wheat photosynthetic heat tolerance.Competing Interest StatementThe authors have declared no competing interest.