Work

Combined NMR and MRI Assessment of Water Status and Migration in Quercus texana Seeds During Dehydration

Year: 2026

Type: article

Abstract: Quercus texana seeds are recalcitrant and thus highly sensitive to desiccation, which makes storage difficult. For practical seed handling, it is important to define their safe water content and to understand how water is distributed during dehydration. The present study utilized magnetic resonance imaging (MRI) and nuclear magnetic resonance (NMR) technologies to investigate the migration and phases of water, respectively, revealing the underlying reasons for the recalcitrance of Q. texana seeds. The water content of fresh Q. texana seeds was found to be 39.6% and the germination percentage was 93.3%. As the water content decreased, the germination percentage decreased continuously, reaching 0% at a water content of 13.0%. At 20.0% water content, the germination percentage was 71.7%. MRI showed that water was primarily stored in the embryo axis and cotyledon center in fresh Q. texana seeds. Water loss occurs in the following order during seed dehydration: embryo axis, cotyledon center, cotyledon periphery, and cotyledon end. However, water in the radicle region persisted until seed water content decreased to 15.0%, at which point no signal was detected. The NMR T2 relaxation spectrum indicated the presence of bound water (T21 = 0.01–5.44 ms) and free water (T22 = 7.19–1401.93 ms) in the seeds. During the dehydration process, most of the water was lost as free water, and the T22 shifted to longer times. Concurrently, the bound water shifted to shorter T21 times. Overall, for practical purposes, seed water should be maintained at or above 20.0%. MRI further showed that water loss from the radicle plays a decisive role in the decline of seed germination, and that protecting the region of radicle and the cupule scar can effectively retard water loss. Furthermore, the bound-water content is positively correlated with seed germination.

Source: Plants

DOI: 10.3390/plants15020250

Authors: Huaitong Wu, Xin Zu, Haoyu Wang, Yuxiao Wang, Shuxian Li, Mingwei Zhu

Institution: Nanjing Forestry University

Language: English

Topic: Seed Germination and Physiology

Subfield: Plant Science

Field: Agricultural and Biological Sciences

Domain: Life Sciences

SDG: Zero hunger

Open Access status: gold

Estimated APC paid: $3,258