Physiological characterization and thylakoid ultrastructure analysis in super high-yield hybrid rice leaves under drought stress

Abstract

Rice serves for more than a third of the world's population. However, drought stress (DS) affects its growth and yield. In order to understand plant drought adaptability, we explored the physiological and thylakoid ultrastructural alteration in super high-yield hybrid rice Liangyoupeijiu (LYPJ) under DS. Results showed that DS altered the thylakoid ultrastructure; twisted and fractured stroma thylakoids and more starch granules in chloroplast of LYPJ were present. Also, DS lowered chlorophyll and carotenoid contents in LYPJ after 7 d. DS reduced the proportion of unsaturated fatty acids in thylakoid membranes and increased the content of linoleic and abscisic acids (ABA) and osmotic substances such as calcium and potassium in LYPJ. Based on these results, we concluded that although DS severely affected normal growth, plants employed various strategies, such as changing their membrane lipid fluidity, increasing endogenous ABA and osmotic substance contents and stabilizing the grana thylakoids, in order to adapt to drought stress.Additional key words: abiotic stress; membrane lipid fluidity; osmotic adjustment; phytohormone. mass; HPLC -high-performance liquid chromatography; IAA -indole-3-acetic acid; IUFA -index of unsaturated fatty acid; OA -osmotic adjustment; PLC -phospholipase C; ROS -reactive oxygen species; RWC -relative water content; SOD -superoxide dismutase; TEM -transmission electron microscope; WW -well-watered.

Changes in photosynthetic and chlorophyll fluorescence characteristics of sorghum under drought and waterlogging stress

“…Such studies have demonstrated similarities in crops, such as canola (Brassica napus L.) and sunflower (Helianthus annuus L.) (Sun et al 2010). In addition, it has also been found that under water stress, the metabolism of crops is disrupted and plant growth is restricted (Waraich et al 2011, Shao et al 2016, which may also explain the changes in morphology during water stress. Chl, the main photosynthetic pigment in plant leaves, is an important indicator used for evaluating the physiological status of plants; it is also an important indicator reflecting the photosynthetic capacity of leaves (Xu et al 2014b).…”

“…With global climate change, the shortage of freshwater resources and the imbalanced distribution of water are becoming more serious each year, and water stress has become the main factor limiting global agricultural production (Tambussi et al 2005, Khan et al 2016. Furthermore, because of the variation in precipitation in recent years, the area of land suffering from water stress is gradually increasing (Kataria et al 2015, Wang et al 2019a. Water stress may arise as a result of waterlogging or water deficit (Guo et al 2018).…”

“…It has been reported that the production of photosynthetic material plays an important role in crop growth and yield formation, and that the production of biomass and the physiological characteristics of crops are greatly affected by water stress (Wang et al 2019a). Extensive studies have shown changes in anatomical and morphological features, such as root architecture, leaf area, and plant height under water stress (Wang et al 2004, Radhakrishnan et al 2012.…”

Negative effects of long‐term exposure to salinity, drought, and combined stresses on halophyte Halogeton glomeratus

“…Drought is one of the harshest abiotic factors inhibiting photosynthesis and thereby restricting plant growth and yield (Alam et al, 2021;Panda et al, 2021). Drought stress limits the efficiency of the photosynthetic apparatus, resulting in substantial damage to the thylakoid membranes, and decrease in photosynthetic pigments (Velikova et al, 2016;Wang et al, 2019). To ensure survival under such an extreme environment, plants employ their own defense system, such as reduced transpiration rate by closing stomata (Rangani et al, 2018;Xi et al, 2018;Yang et al, 2021).…”

Exogenous application of 5-aminolevulinic acid alleviated damage to wheat chloroplast ultrastructure under drought stress by transcriptionally regulating genes correlated with photosynthesis and chlorophyll biosynthesis

“…Drought stress significantly inhibits the growth of plants because it can cause the Communicated by H. Peng. accumulation of reactive oxygen species (ROS), destroy the chloroplast structure, break the thylakoid matrix, decrease the chlorophyll content (Wang et al 2019b), reduce the activity of related enzymes in the photosynthetic carbon reduction cycle (Ramachandra Reddy et al 2004), change the regulation of chloroplast proteins (Chang et al 2019), and reduce the photosynthetic rate (Nxele et al 2017;Khan et al 2019).…”