Common reed produces starch granules at the shoot base in response to salt stress.
Common reed (Phragmites australis) is a well known salt-tolerant plant and it is suggested that reeds recover Na(+) in the xylem sap of the shoot base (basal part of the shoot), store it temporarily in the shoot base, release it into the phloem sap, and then retranslocate it to the roots. To investigate whether Na(+) is retained in the shoot base of reeds, confocal laser scanning microscope (CLSM) observations were conducted using an intracellular Na(+)-specific fluorescent probe. The CLSM observations revealed that reeds produced a large number of the starch granules at the shoot base when salt-stressed, and that the fluorescence indicating the location of intracellular free Na(+) was observed in the same position as the starch granules. The Na content of starch granules was considerably greater than that of the shoot base, whereas the potassium (K) contents of the granules was only slightly greater than that of the shoot base. Reeds produced Na(+)-binding starch granules in the parenchyma cells of the shoot base when salt-stressed; these starch granules may decrease intracellular free Na(+). It is proposed that the site-specific production of Na(+)-binding starch granules constitutes a novel salt tolerance mechanism.
Kanai
Masatake
M
Department of Applied Biology and Chemistry, Faculty of Applied Bio-Science, Tokyo University of Agriculture, Setagaya-ku, Tokyo 156-8502, Japan.
Higuchi
Kyoko
K
Department of Applied Biology and Chemistry, Faculty of Applied Bio-Science, Tokyo University of Agriculture, Setagaya-ku, Tokyo 156-8502, Japan.
Hagihara
Takashi
T
Department of Applied Biology and Chemistry, Faculty of Applied Bio-Science, Tokyo University of Agriculture, Setagaya-ku, Tokyo 156-8502, Japan.
Konishi
Teruko
T
Forestry and Forest Products Research Institute, PO Box 16, Tsukuba Norin Kenkyu Danchinai, Ibaraki 305-8687, Japan.
Ishii
Tadashi
T
Forestry and Forest Products Research Institute, PO Box 16, Tsukuba Norin Kenkyu Danchinai, Ibaraki 305-8687, Japan.
Fujita
Naoko
N
Department of Biological Production, Akita Prefectural University, Akita City, Akita 010-0195, Japan.
Nakamura
Yasunori
Y
Department of Biological Production, Akita Prefectural University, Akita City, Akita 010-0195, Japan.
Maeda
Yoshiyuki
Y
Department of Applied Biology and Chemistry, Faculty of Applied Bio-Science, Tokyo University of Agriculture, Setagaya-ku, Tokyo 156-8502, Japan.
Yoshiba
Masaaki
M
Department of Applied Biology and Chemistry, Faculty of Applied Bio-Science, Tokyo University of Agriculture, Setagaya-ku, Tokyo 156-8502, Japan.
Tadano
Toshiaki
T
Department of Applied Biology and Chemistry, Faculty of Applied Bio-Science, Tokyo University of Agriculture, Setagaya-ku, Tokyo 156-8502, Japan.
D000222:Adaptation, Physiological; D052585:Phloem / Q000378:metabolism; D018517:Plant Roots / Q000378:metabolism; D018520:Plant Shoots / Q000378:metabolism*; D006109:Poaceae / Q000378:metabolism*; D012965:Sodium Chloride / Q000378:metabolism*; D013213:Starch / Q000378:metabolism*; D052584:Xylem / Q000378:metabolism
D012965:Sodium Chloride; D013213:Starch