Age-related mechanism and its relationship with secondary metabolism and abscisic acid in Aristotelia chilensis plants subjected to drought stress

Abstract

Drought stress is the most important stress factor for plants, being the main cause of agricultural crop loss in the world. Plants have developed complex mechanisms for preventing water loss and oxidative stress such as synthesis of abscisic acid (ABA) and non-enzymatic antioxidant compounds such as anthocyanins, which might help plants to cope with abiotic stress as antioxidants and for scavenging reactive oxygen species. A. chilensis (Mol.) is a pioneer species, colonizing and growing on stressed and disturbed environments. In this research, an integrated analysis of secondary metabolism in Aristotelia chilensis was done to relate ABA effects on anthocyanins biosynthesis, by comparing between young and fully-expanded leaves under drought stress. Plants were subjected to drought stress for 20 days, and physiological, biochemical, and molecular analyses were performed. The relative growth rate and plant water status were reduced in stressed plants, with young leaves significantly more affected than fully-expanded leaves beginning from the 5th day of drought stress. A. chilensis plants increased their ABA and total anthocyanin content and showed upregulation of gene expression when they were subjected to severe drought (day 20), with these effects being higher in fully-expanded leaves. Multivariate analysis indicated a significant positive correlation between transcript levels for NCED1 (9-cis-epoxycarotenoid dioxygenase) and UFGT (UDP glucose: flavonoid-3-O-glucosyltransferase) with ABA and total anthocyanin, respectively. Thus, this research provides a more comprehensive analysis of the mechanisms that allow plants to cope with drought stress. This is highlighted by the differences between young and fully-expanded leaves, showing different sensibility to stress due to their ability to synthesize anthocyanins. In addition, this ability to synthesize different and high amounts of anthocyanins could be related to higher NCED1 and MYB expression and ABA levels, enhancing drought stress tolerance.

Abscisic acid is involved in phenolic compounds biosynthesis, mainly anthocyanins, in leaves of Aristotelia chilensis plants (Mol.) subjected to drought stress

“…Micropropagated in‐vitro Maqui plants ( A. chilensis ) donated by BestPlant Co. (Curicó, Chile) were used in this study. One‐year‐old plants were transplanted to 2 l pots with Andisol soil and acclimated in a greenhouse (temperature: 25 ± 3°C; photoperiod: light 16/8 h dark; humidity: 60–70%; and a mean photosynthetic active radiation at midday of 300 μmol m −2 s −1 ) for 2 weeks as described previously in González‐Villagra et al (). Plants were then divided into two groups (20 plants for each group): daily irrigated (DI) and non‐irrigated (NI).…”

“…The DI plants were irrigated at field capacity; meanwhile, NI plants were exposed to water withholding to initiate drought stress. When NI plants were stressed [the 20th day of drought stress, based on previous study of González‐Villagra et al ], 100 μM Fluridone (Sigma, St. Louis, MO) was homogenously applied by spraying on a group of NI and DI plants (+FLU). After 24 h, in some cases, leaves were sprayed with a solution of 100 μM ABA (Sigma; +ABA).…”

Chemical Composition and Antioxidant Potential Differences between Cynomorium coccineum L. Growing in Italy and in Tunisia: Effect of Environmental Stress

“…In the Sardinian samples, anthocyanins seem to be almost equally distributed in the ethyl acetate, acetone, methanol, and water extracts, whereas in the Tunisian samples, the majority of anthocyanins were extracted by acetone. On the whole, Tunisian Cynomorium is richer in anthocyanins (p < 0.05), confirming the role of these chemicals in the prevention of drought stress [2]. In addition, the different extraction patterns suggest a different chemical composition in this phenolic sub-class.…”

“…A 10 mg aliquot of each dried extracts was resuspended in 600 µL of D 2 1 H− 1 H total correlation spectroscopy (TOCSY) experiments were performed with a spectral width of 6000 Hz in both dimensions, an acquisition time of 0.171 s, a delay time of 1.0 s, number of scans of 128 and number of data points of 2048 (f2) and 256 (f1). TOCSY experiments were performed in phase-sensitive mode.…”

Shifts in Leaf and Branch Elemental Compositions of Pinus massoniana (Lamb.) Following Three-Year Rainfall Exclusion

“…Global climate change is modifying patterns of global precipitation, leading to changes in the frequency and magnitude of extreme climatic events, such as drought [1,2]. Increased drought enhances tree mortality [3,4] and influences ecosystem biodiversity as well as ecosystem structure and function [5][6][7][8]. Several studies have shown that terrestrial plants adapted and resistant to drought can alter their physiological characteristics to increase water use efficiencies to prevent death [9][10][11].…”