Identification of the initial water-site and movement in Gleditsia sinensis seeds and its relation to seed coat structure

Abstract Background Water uptake is essential for seed germination. However, Gleditsia sinensis seeds have a water-impermeable coat, which beneficial its adaption to the environment, but prohibits germination without treatment. This feature may be associated with structure of coat. Thus, aim this research was identify and describe initial water site movement determine relationship between coat absorption. Results A temperature 80 °C optimal break hardseededness G. seeds. Scanning electron microscopy (SEM) images revealed that consisted palisade layer light line can hinder entry into seed. Also, vascular bundles existed in hilar region. Hot treatment caused tightly closed micropyle open cavity beneath it expanded; cells lens raised. The embryo dye-tracking tests showed radicle tip region stained red. After staining 24 h, red-stained area on bundle side cotyledon more extensive than other side. Further studies by MRI maps indicated imbibition. Some then migrated along space endosperm chalazal; simultaneously, rest reached embryonic axis spread cotyledons. 20–24 h unevenly distributed within cotyledons way edge parts were hydrated center. Blocking an important during medial chalazal portion capable imbibing when blocked, absorption later slower through Conclusion technology provides promising non-invasive technique gap path Combined results SEM, relation imbibition inferred.