Premium
The role of lateral roots in bypass flow in rice ( Oryza sativa L.)
Author(s) -
FAIYUE BUALUANG,
ALAZZAWI MOHAMMED J.,
FLOWERS TIMOTHY J.
Publication year - 2010
Publication title -
plant, cell and environment
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.646
H-Index - 200
eISSN - 1365-3040
pISSN - 0140-7791
DOI - 10.1111/j.1365-3040.2009.02078.x
Subject(s) - apoplast , oryza sativa , xylem , fluorescence microscope , transpiration stream , biophysics , confocal laser scanning microscopy , stele , chemistry , botany , plasmodesma , biology , fluorescence , transpiration , cell wall , biochemistry , physics , photosynthesis , quantum mechanics , gene
Although an apoplastic pathway (the so‐called bypass flow) is implicated in the uptake of Na + by rice growing in saline conditions, the point of entry of this flow into roots remains to be elucidated. We investigated the role of lateral roots in bypass flow using the tracer trisodium‐8‐hydroxy‐1,3,6‐pyrenetrisulphonic acid (PTS) and the rice cv. IR36. PTS was identified in the vascular tissue of lateral roots using both epifluorescence microscopy and confocal laser scanning microscopy. Cryo‐scanning electron microscopy and epifluorescence microscopy of sections stained with berberine‐aniline blue revealed that the exodermis is absent in the lateral roots. We conclude that PTS can move freely through the cortical layers of lateral roots, enter the stele and be transported to the shoot via the transpiration stream.