Characterization of Root System Architecture Traits in Diverse Soybean Genotypes Using a Semi-Hydroponic System
Shuo Liu,
Naheeda Begum,
Tingting An,
Tuanjie Zhao,
Bingcheng Xu,
Suiqi Zhang,
Xiping Deng,
Hon-Ming Lam,
Henry T. Nguyen,
Kadambot H. M. Siddique,
Yinglong Chen
Affiliations
Shuo Liu
College of Natural Resources and Environment, and State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Northwest A&F University, Xi’an 712100, China
Naheeda Begum
National Center for Soybean Improvement, Key Laboratory of Biology and Genetics and Breeding for Soybean, Ministry of Agriculture, State Key Laboratory for Crop Genetics and Germplasm Enhancement, Nanjing Agricultural University, Nanjing 210095, China
Tingting An
College of Natural Resources and Environment, and State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Northwest A&F University, Xi’an 712100, China
Tuanjie Zhao
National Center for Soybean Improvement, Key Laboratory of Biology and Genetics and Breeding for Soybean, Ministry of Agriculture, State Key Laboratory for Crop Genetics and Germplasm Enhancement, Nanjing Agricultural University, Nanjing 210095, China
Bingcheng Xu
College of Natural Resources and Environment, and State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Northwest A&F University, Xi’an 712100, China
Suiqi Zhang
College of Natural Resources and Environment, and State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Northwest A&F University, Xi’an 712100, China
Xiping Deng
College of Natural Resources and Environment, and State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Northwest A&F University, Xi’an 712100, China
Hon-Ming Lam
Center for Soybean Research of the State Key Laboratory of Agrobiotechnology, School of Life Sciences, The Chinese University of Hong Kong, Shatin, Hong Kong, China
Henry T. Nguyen
Division of Plant Sciences, University of Missouri, Columbia, MO 65211, USA
Kadambot H. M. Siddique
The UWA Institute of Agriculture, School of Agriculture and Environment, The University of Western Australia, Perth 6009, Australia
Yinglong Chen
College of Natural Resources and Environment, and State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Northwest A&F University, Xi’an 712100, China
Phenotypic variation and correlations among root traits form the basis for selecting and breeding soybean varieties with efficient access to water and nutrients and better adaptation to abiotic stresses. Therefore, it is important to develop a simple and consistent system to study root traits in soybean. In this study, we adopted the semi-hydroponic system to investigate the variability in root morphological traits of 171 soybean genotypes popularized in the Yangtze and Huaihe River regions, eastern China. Highly diverse phenotypes were observed: shoot height (18.7–86.7 cm per plant with a median of 52.3 cm); total root length (208–1663 cm per plant with a median of 885 cm); and root mass (dry weight) (19.4–251 mg per plant with a median of 124 mg). Both total root length and root mass exhibited significant positive correlation with shoot mass (p ≤ 0.05), indicating their relationship with plant growth and adaptation strategies. The nine selected traits contributed to one of the two principal components (eigenvalues > 1), accounting for 78.9% of the total genotypic variation. Agglomerative hierarchical clustering analysis separated the 171 genotypes into five major groups based on these root traits. Three selected genotypes with contrasting root systems were validated in soil-filled rhizoboxes (1.5 m deep) until maturity. Consistent ranking of the genotypes in some important root traits at various growth stages between the two experiments indicates the reliability of the semi-hydroponic system in phenotyping root trait variability at the early growth stage in soybean germplasms.
