TY - JOUR
T1 - Large crown root number improves topsoil foraging and phosphorus acquisition
AU - Sun, Baoru
AU - Gao, Yingzhi
AU - Lynch, Jonathan P.
N1 - Funding Information:
1 B.R.S. was supported by the China Scholarship Council and the National Key Basic Research Program of China (2016YFC0500703). Research costs were supported by the Agriculture and Food Research Initiative of the USDA National Institute of Food and Agriculture competitive grant 2014-67013-2157 to J.P.L. 2 Address correspondence to jpl4@psu.edu.
Publisher Copyright:
Copyright © 2018 American Society of Plant Biologists. All rights reserved.
PY - 2018
Y1 - 2018
N2 - Suboptimal phosphorus (P) availability is a primary constraint to plant growth on Earth. We tested the hypothesis that maize (Zea mays) genotypes with large crown root number (CN) will have shallower rooting depth and improved P acquisition from low-P soils. Maize recombinant inbred lines with contrasting CN were evaluated under suboptimal P availability in greenhouse mesocosms and the field. Under P stress in mesocosms, the large-CN phenotype had 48% greater root respiration, 24% shallower rooting depth, 32% greater root length density in the topsoil, 37% greater leaf P concentration, 48% greater leaf photosynthesis, 33% greater stomatal conductance, and 44% greater shoot biomass than the small-CN phenotype. Under P stress in the field, the large-CN phenotype had 32% shallower rooting depth, 51% greater root length density in the topsoil, 44% greater leaf P concentration, 18% greater leaf photosynthesis, 21% greater stomatal conductance, 23% greater shoot biomass at anthesis, and 28% greater yield than the small-CN phenotype. These results support the hypothesis that large CN improves plant P acquisition from low-P soils by reducing rooting depth and increasing topsoil foraging. The large-CN phenotype merits consideration as a selection target to improve P capture in maize and possibly other cereal crops.
AB - Suboptimal phosphorus (P) availability is a primary constraint to plant growth on Earth. We tested the hypothesis that maize (Zea mays) genotypes with large crown root number (CN) will have shallower rooting depth and improved P acquisition from low-P soils. Maize recombinant inbred lines with contrasting CN were evaluated under suboptimal P availability in greenhouse mesocosms and the field. Under P stress in mesocosms, the large-CN phenotype had 48% greater root respiration, 24% shallower rooting depth, 32% greater root length density in the topsoil, 37% greater leaf P concentration, 48% greater leaf photosynthesis, 33% greater stomatal conductance, and 44% greater shoot biomass than the small-CN phenotype. Under P stress in the field, the large-CN phenotype had 32% shallower rooting depth, 51% greater root length density in the topsoil, 44% greater leaf P concentration, 18% greater leaf photosynthesis, 21% greater stomatal conductance, 23% greater shoot biomass at anthesis, and 28% greater yield than the small-CN phenotype. These results support the hypothesis that large CN improves plant P acquisition from low-P soils by reducing rooting depth and increasing topsoil foraging. The large-CN phenotype merits consideration as a selection target to improve P capture in maize and possibly other cereal crops.
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U2 - 10.1104/pp.18.00234
DO - 10.1104/pp.18.00234
M3 - Article
C2 - 29618638
AN - SCOPUS:85058816692
VL - 177
SP - 90
EP - 104
JO - Plant Physiology
JF - Plant Physiology
SN - 0032-0889
IS - 1
ER -