Dynamic in vivo monitoring of granum structural changes of Ctenanthe setosa (Roscoe) Eichler during drought stress and subsequent recovery

• DOI: 10.1111/ppl.14621
• Publication Date: 2025-01-23T06:59:36Z
• Authors: Richard Hembrom; Renáta Ünnep; Éva Sárvári; Gergely Nagy; Katalin Solymosi

Abstract Investigating the effects of drought stress and subsequent recovery on structure function chloroplasts is essential to understanding how plants adapt environmental stressors. We investigated Ctenanthe setosa (Roscoe) Eichler, an ornamental plant that can tolerate prolonged periods (40 49 days water withdrawal). Conventional biochemical, biophysical, physiological (ultra)structural methods combined for first time in a higher with vivo small‐angle neutron scattering (SANS) were used characterize alterations induced by recovery. Upon stress, no significant changes occurred chloroplast ultrastructure, chlorophyll content, 77K fluorescence emission spectra maximal quantum efficiency PSII (Qy dark), but actual light) decreased, amounts PSI‐LHCII complexes monomers declined, supercomplexes increased. Thickness leaf adaxial hypodermis, length granum repeat distance (RD) values decreased upon as shown light microscopy SANS, respectively. Because very slight (nm‐range) RD values, large biological variability (significant differences among leaves studied regions) invasive sampling required this method, transmission electron (TEM) hardly showed differences. On other side, situ SANS analyses provided unique insight into fast structural drought‐stressed leaves, which happened already 18 h after re‐watering, while functional biochemical took place longer scale.