TY - JOUR

T1 - Timing matters: Distinct effects of nitrogen and phosphorus fertilizer application timing on root system architecture responses

AU - van Duijnen, Richard

AU - Uther, Hannah

AU - Härdtle, Werner

AU - Temperton, Vicky

AU - Kumar, Amit

N1 - This publication was funded by the Open Access Publication Fund of Leuphana University Lüneburg. Funding Information: We thank Farida Samad‐zada and the DAAD RISE program as well as Justin Raeder, Constanza Berron, and Hannes Eggerts for essential help in processing and analyzing root samples. We also thank Thomas Niemeyer for his excellent technical support and construction of the photobox, Benjamin M. Delory for his assistance on R root data analysis, and Saatzucht Breun for supplying the Barke seeds free of charge. This research was funded by the BonaRes soil sustainability program of the German Ministry for Education and Research (BMBF) Germany within the INPLAMINT project subproject H at Leuphana University Lüneburg (grant numbers: 031A561H and 031B0508H). The authors declare no conflict of interests. Publisher Copyright: © 2021 The Authors. Plant-Environment Interactions published by John Wiley & Sons Ltd and New Phytologist Foundation.

PY - 2021/8/1

Y1 - 2021/8/1

N2 - Aims: Although different plant foraging responses to the two macronutrients nitrogen (N) and phosphorus (P) are well researched, the effect of timing of fertilizer application on root system architecture (RSA) remains largely unknown. We, therefore, aimed to understand how RSA of Hordeum vulgare L. responds to timing of N and P application. Methods: Plants were grown in rhizoboxes for 38 days in nutrient-poor soil and watered with nutrient solution, lacking either N or P, with the absent nutrient applied once either 2/3/4 weeks after sowing. Positive controls were continuously receiving N and P and a negative control receiving both N and P only after 3 weeks. We tracked root growth over time, measured plant biomass and nutrient uptake. Results: Late N application strongly reduced total root biomass and visible root length compared with continuous NP and late P application. Root mass fractions (total root biomass/total plant biomass) remained similar over all treatments, but relative allocation (% of total root biomass) was higher in lower depth with late N application. Shoot P concentrations remained relatively stable, but the plants receiving P later had higher N concentrations. Conclusions: Late N application had overall more negative effects on early plant growth compared with late P. We propose that future studies under field conditions should try to disentangle the effect of timing from the nutrient availability on RSA responses and hence ultimately plant performance.

AB - Aims: Although different plant foraging responses to the two macronutrients nitrogen (N) and phosphorus (P) are well researched, the effect of timing of fertilizer application on root system architecture (RSA) remains largely unknown. We, therefore, aimed to understand how RSA of Hordeum vulgare L. responds to timing of N and P application. Methods: Plants were grown in rhizoboxes for 38 days in nutrient-poor soil and watered with nutrient solution, lacking either N or P, with the absent nutrient applied once either 2/3/4 weeks after sowing. Positive controls were continuously receiving N and P and a negative control receiving both N and P only after 3 weeks. We tracked root growth over time, measured plant biomass and nutrient uptake. Results: Late N application strongly reduced total root biomass and visible root length compared with continuous NP and late P application. Root mass fractions (total root biomass/total plant biomass) remained similar over all treatments, but relative allocation (% of total root biomass) was higher in lower depth with late N application. Shoot P concentrations remained relatively stable, but the plants receiving P later had higher N concentrations. Conclusions: Late N application had overall more negative effects on early plant growth compared with late P. We propose that future studies under field conditions should try to disentangle the effect of timing from the nutrient availability on RSA responses and hence ultimately plant performance.

KW - Ecosystems Research

KW - barley

KW - fertilizer

KW - functional traits

KW - rhizobox

KW - root system architecture

KW - root traits

KW - timing

KW - barley

KW - fertilizer

KW - funtional traits

KW - rhizobox

KW - root system architecture

KW - root traits

KW - timing

UR - http://www.scopus.com/inward/record.url?scp=85124879090&partnerID=8YFLogxK

U2 - 10.1002/pei3.10057

DO - 10.1002/pei3.10057

M3 - Journal articles

C2 - 37283701

VL - 2

SP - 194

EP - 205

JO - Plant-Environment Interactions

JF - Plant-Environment Interactions

SN - 2575-6265

IS - 4

ER -