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  • Strigolactone roles in maize tolerance to low nitrogen involve shifts in acquisition and partitioning of protein, sulfur, and iron
Title: Strigolactone roles in maize tolerance to low nitrogen involve shifts in acquisition and partitioning of protein, sulfur, and iron
Abstract Background and AimsNitrogen (N) is an essential macronutrient that can limit plant development and crop yield through widespread physiological and molecular impacts. In maize, N-starvation enhances biosynthesis and exudation of strigolactones (SLs) in a process reversible by nitrate addition and consequent repression of genes for SL biosynthesis. MethodsIn the present study, a maize mutant deficient in SL biosynthesis (zmccd8) allowed an in-depth analysis of SL contributions under low N. Both hydroponic and field conditions were used to better characterize the response of the mutant to N availability. ResultsThe severity of responses to N-limitation by the SL-deficientzmccd8mutant extended from growth parameters to content of iron, sulfur, protein, and photosynthetic pigments, as well as pronounced impacts on expression of key genes, which could be crucial molecular target for the SL-mediated acclimatation to N shortage. ConclusionsOur results demonstrate that SLs are critical for physiological acclimation to N deficiency by maize and identify central players in this action. Further contributions by iron and sulfur are implicated in the complex pathway underlying SL modulation of responses to N-deprivation, thus widening our knowledge on SL functioning and providing new hints on their potential use in agriculture.  more » « less
Award ID(s):
1748105
PAR ID:
10543417
Author(s) / Creator(s):
; ; ; ; ; ; ;
Publisher / Repository:
Springer
Date Published:
Journal Name:
Plant and Soil
ISSN:
0032-079X
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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