Photosynthesis in newly-developed leaves of heat-tolerant wheat acclimates to long-term nocturnal warming

We examined photosynthetic capacity of newly-developed and pre-existing flag leaves of four wheat genotypes under three night temperatures (15, 20 and 25 °C) and common day temperature of 26 °C in two controlled environment experiments. In newly-developed leaves which acclimated (i.e. maintained or increased) the maximum rate of net CO2 assimilation (An) to long-term (9–13 weeks) nocturnal warming, acclimation was underpinned by greater capacity of Rubisco carboxylation (Vcmax) and photosynthetic electron transport (J). This indicates a night-dependent temperature sensitivity of the activation state of Rubisco. Metabolite profiling linked acclimation of An to greater accumulation of monosaccharides and saturated fatty acids in leaves, suggesting roles for osmotic adjustment of leaf turgor pressure and maintenance of cell membrane integrity. By contrast, warm night-induced inhibition of An was related to reductions in stomatal conductance of CO2 and J, despite higher basal electron trans..., Tcrit: leaf discs were excised during the day from the middle section of detached dark-adapted and were exposed to a temperature ramp at a constant rate of 1°C min−1 from 20 to 65 °C with simultaneous continuous measurement of F0 taken. Tcrit was calculated as the intersection point of two regression lines extrapolated from the flat and steep portion of the F0–temperature response curve.
Leaf gas exchange and An-Ci curves: Five LI-COR portable photosynthesis systems (LI-6400XT, LI-COR Inc., Lincoln, NE, USA) were used for gas exchange measurements. The LI-COR units were fitted with 6 cm2 leaf chambers with red-blue light source (6400-18 RGB Light Source, LI-COR). Leaves were exposed to saturating irradiance of 1500 μmol photons m−2 s−1 within the LI-COR leaf chamber, with both the LI-COR leaf chamber/block, and the whole plants were placed within the temperature-controlled cabinet. The LI-COR leaf chamber was initially set to 20°C, reference line atmospheric [CO2] of 400 ppm, a flow rat..., MS Excel and R/R Studio., This README file was generated on 2023-11-02 by Onoriode Coast.

GENERAL INFORMATION

1. Title of Dataset: Photosynthesis in newly-developed leaves of heat-tolerant wheat acclimates to long-term nocturnal warming
2. Author Information
A. Principal Investigator Contact Information
Name: Onoriode Coast
Institution: University of New England
Address: Armidale, NSW Australia
Email: [e-mail]

B. Co-investigator Contact Information
Name: Andrew P. Scafaro
Institution: Australian National University
Address: Canberra, ACT Australia
Email: [e-mail]

C. Co-investigator Contact Information
Name: Helen Bramley
Address: Hobart, TAS Australia
Email: [e-mail]

D. Co-investigator Contact Information
Name: Nicolas L. Taylor
Institution: University of Western Australian
Address: Crawley, WA Australia
Email: [e-mail]

E. Co-investigator Contact Information
Name: Owen...