AUTHOR=Yuan Wei , Zhang Qian , Li Ying , Wang Qianwen , Xu Feiyun , Dang Xiaolin , Xu Weifeng , Zhang Jianhua , Miao Rui 

TITLE=RETRACTED: Abscisic Acid Is Required for Root Elongation Associated With Ca2+ Influx in Response to Water Stress

JOURNAL=Frontiers in Plant Science

VOLUME=11

YEAR=2020

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2020.00332

DOI=10.3389/fpls.2020.00332

ISSN=1664-462X

ABSTRACT=<p>Abscisic acid (ABA) is a critical hormone for plant survival under water stress. In this study, large-scale mutants of the <italic>Arabidopsis</italic> ecotype Columbia-0 (Col-0) were generated by ethyl methanesulfonate (EMS)-mutagenesis, and an <italic><underline>i</underline>mproved <underline>r</underline>oot <underline>e</underline>longation under <underline>w</underline>ater-stress 1 (irew1)</italic> mutant showing significantly enhanced root growth was isolated under a water potential gradient assay. Then, <italic>irew1</italic> and ABA-related mutants in <italic>Arabidopsis</italic> or tomato plants were observed under water potential gradient assay or water-deficient conditions. ABA pathway, Ca<sup>2+</sup> response, and primary root (PR) elongation rate were monitored in addition to DNA- and RNA-Seq analyses. We found that based on phenotyping and transcriptional analyses, <italic>irew1</italic> exhibited enhanced PR growth, ABA, and Ca<sup>2+</sup> responses, compared to wild type subjected to water stress. Interestingly, exogenous Ca<sup>2+</sup> application enhanced PR growth of <italic>irew1</italic>, ABA-biosynthesis deficient mutants in <italic>Arabidopsis</italic>, and tomato plants, in response to water potential gradients or water-deficient conditions. In combination with other ABA-related mutants and pharmacological studies, our results suggest that ABA is required for root elongation associated with Ca<sup>2+</sup> influx in response to water stress.</p>