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Title: Interactions between root hairs and the soil microbial community affect the growth of maize seedlings
Abstract Root hairs are considered important for rhizosphere formation, which affects root system functioning. Through interactions with soil microorganisms mediated by root exudation, root hairs may affect the phenotypes and growth of young plants. We tested this hypothesis by integrating results from two experiments: (1) a factorial greenhouse seedling experiment withZea mays B73‐wtand its root‐hairless mutant,B73‐rth3, grown in live and autoclaved soil, quantifying 15 phenotypic traits, seven growth rates, and soil microbiomes and (2) a semi‐hydroponic system quantifying root exudation of maize genotypes. Possibly as compensation for lacking root hairs,B73‐rth3seedlings allocated more biomass to roots and grew slower thanB73‐wtseedlings in live soil, whereasB73‐wtseedlings grew slowest in autoclaved soil, suggesting root hairs can be costly and their benefits were realized with more complete soil microbial assemblages. There were substantial differences in root exudation between genotypes and in rhizosphere versus non‐rhizosphere microbiomes. The microbial taxa enriched in the presence of root hairs generally enhanced growth compared to taxa enriched in their absence. Our findings suggest the root hairs' adaptive value extends to plant‐microbe interactions mediated by root exudates, affecting plant phenotypes, and ultimately, growth.  more » « less
Award ID(s):
2050574
PAR ID:
10583275
Author(s) / Creator(s):
; ; ; ; ;
Publisher / Repository:
WILEY
Date Published:
Journal Name:
Plant, Cell & Environment
Volume:
47
Issue:
2
ISSN:
0140-7791
Page Range / eLocation ID:
611 to 628
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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