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Rice plants respond to ammonium stress by adopting a helical root growth pattern
Author(s) -
Jia Letian,
Xie Yuanming,
Wang Zhen,
Luo Long,
Zhang Chi,
Pélissier PierreMathieu,
Parizot Boris,
Qi Weicong,
Zhang Jing,
Hu Zhubing,
Motte Hans,
Luo Le,
Xu Guohua,
Beeckman Tom,
Xuan Wei
Publication year - 2020
Publication title -
the plant journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 3.058
H-Index - 269
eISSN - 1365-313X
pISSN - 0960-7412
DOI - 10.1111/tpj.14978
Subject(s) - auxin , ammonium , arabidopsis , oryza sativa , root hair , ammonium acetate , biology , elongation , botany , chemistry , biochemistry , materials science , gene , mutant , chromatography , high performance liquid chromatography , organic chemistry , ultimate tensile strength , metallurgy
SUMMARY High levels of ammonium nutrition reduce plant growth and different plant species have developed distinct strategies to maximize ammonium acquisition while alleviating ammonium toxicity through modulating root growth. To date, the mechanisms underlying plant tolerance or sensitivity towards ammonium remain unclear. Rice ( Oryza sativa ) uses ammonium as its main N source. Here we show that ammonium supply restricts rice root elongation and induces a helical growth pattern, which is attributed to root acidification resulting from ammonium uptake. Ammonium‐induced low pH triggers the asymmetric distribution of auxin in rice root tips through changes in auxin signaling, thereby inducing a helical growth response. Blocking auxin signaling completely inhibited this root response. In contrast, this root response is not activated in ammonium‐treated Arabidopsis. Acidification of Arabidopsis roots leads to the protonation of indole‐3‐acetic acid and dampening of the intracellular auxin signaling levels that are required for maintaining root growth. Our study suggests a different mode of action by ammonium on the root pattern and auxin response machinery in rice versus Arabidopsis, and the rice‐specific helical root response towards ammonium is an expression of the ability of rice to moderate auxin signaling and root growth to utilize ammonium while confronting acidic stress.