Plant water stress: Associations between ethylene and abscisic acid response

Abstract

Agriculture is severely impacted by water stress due either to excess (hypoxia/anoxia) or deficit of water availability. Hypoxia/anoxia is associated with oxygen (O 2 ) deficiency or depletion, inducing several anatomical, morphological, physiological, and molecular changes. The majority of these alterations are adaptive mechanisms to cope with low O 2 availability; among them, alterations in shoot length, aerenchyma formation and adventitious roots have been described in several studies. The aim of this review was to address the association between abscisic acid (ABA) and ethylene in function of water availability in plants. The major physiological responses to low O 2 are associated with changes in root respiration, stomatal conductance, photosynthesis, and fermentation pathways in roots. In addition, several changes in gene expression have been associated with pathways that are not present under normal O 2 supply. The expression of ethylene receptor genes is up-regulated by low O 2 , and ethylene seems to have a crucial role in anatomical and physiological effects during hypoxia/anoxia. During O 2 depletion, ethylene accumulation down-regulates ABA by inhibiting rate-limiting enzymes in ABA biosynthesis and by activating ABA breakdown to phaseic acid. With regard to water deficit, drought is primarily sensed by the roots, inducing a signal cascade to the shoots via xylem causing physiological and morphological changes. Several genes are regulated up or down with osmotic stress; the majority of these responsive genes can be driven by either an ABA-dependent or ABA-independent pathway. Some studies suggest that ethylene shuts down leaf growth very fast after the plant senses limited water availability. Ethylene accumulation can antagonize the control of gas exchange and leaf growth upon drought and ABA accumulation.

Differential expression of the genes involved in responses to water-deficit stress in peach trees cv. Chimarrita grafted onto two different rootstocks

“…Among the metabolic changes induced in plants under abiotic stress, the most important one is the accumulation of osmoregulatory molecules composed of organic acids, sugars, and amino acids, which act in the osmotic adjustment, considered to be a typical response to water-deficit in plants (Krasensky and Jonak 2012;Jiménez et al 2013;Salazar et al 2015).…”

A Multi‐Omics Analysis of Glycine max Leaves Reveals Alteration in Flavonoid and Isoflavonoid Metabolism Upon Ethylene and Abscisic Acid Treatment

“…[1] These phytohormones are involved in the fine-tuning of almost all metabolic processes starting from seed germination to senescence and during both normal and abnormal (stress and disease) growth conditions. Among them, ET and ABA are of particular interest as these are the crucial components of stress response in plants, [2][3][4][5] and which are the target molecules of our laboratory. ET is the first gaseous hormone identified in plants that exhibited profound…”

Perubahan morfologis dan anatomis kelapa sawit pada rezim air dan salinitas berbeda

“…Hormon tanaman berupa gas (etilen) juga mengalami akumulasi di perakaran tanaman karena tidak dapat dilepaskan ke rizosfer (Salazar et al, 2015;Voesenek & Bailey-Serres, 2015). Kondisi hipoksia pada rizosfer tidak hanya menyebabkan cekaman pada sistem perakaran karena hilangnya kemampuan untuk menyerap O 2 , air, dan nutrisi, namun juga dapat menarik O 2 keluar dari jaringan akar akibat perbedaan konsentrasi (Kim et al, 2016).…”