Root hair phenotypes influence nitrogen acquisition in maize. (6th August 2021)

• Record Type: Journal Article
• Authors: Saengwilai, Patompong; Strock, Christopher; Rangarajan, Harini; Chimungu, Joseph; Salungyu, Jirawat; Lynch, Jonathan P
• Is Part Of: Annals of botany. Volume 128:Number 7(2022)
• Page Start: 849
• Page End: 858
• Publication Date: 2021-08-06
• Subjects: Ammonium -- maize -- nitrate -- nitrogen -- roots -- root hairs -- SimRoot -- Zea mays; Botany -- Periodicals; 580
• DOI: 10.1093/aob/mcab104
• Languages: English
• ISSNs: 0305-7364

Abstract

Abstract: Background and Aims: The utility of root hairs for nitrogen (N) acquisition is poorly understood. Methods: We explored the utility of root hairs for N acquisition in the functional–structural model SimRoot and with maize genotypes with variable root hair length (RHL) in greenhouse and field environments. Key Results: Simulation results indicate that long, dense root hairs can improve N acquisition under varying N availability. In the greenhouse, ammonium availability had no effect on RHL and low nitrate availability increased RHL, while in the field low N reduced RHL. Longer RHL was associated with 216 % increase in biomass and 237 % increase in plant N content under low-N conditions in the greenhouse and a 250 % increase in biomass and 200 % increase in plant N content in the field compared with short-RHL phenotypes. In a low-N field environment, genotypes with long RHL had 267 % greater yield than those with short RHL. We speculate that long root hairs improve N capture by increased root surface area and expanded soil exploration beyond the N depletion zone surrounding the root surface. Conclusions: We conclude that root hairs play an important role in N acquisition. We suggest that root hairs merit consideration as a breeding target for improved N acquisition in maize and other crops.