Evolution de la structure plastidiale et des reserves polysaccharidiques au cours de la déshydratation des gamétophytes feuillés duPolytrichum formosumHedw. (Polytrichales)
作者:
HalletJ.N.,
MansourK. S.,
LecocqF. M.,
期刊:
Journal of Bryology
(Taylor Available online 1987)
卷期:
Volume 14,
issue 4
页码: 765-777
ISSN:0373-6687
年代: 1987
DOI:10.1179/jbr.1987.14.4.765
出版商: Taylor&Francis
数据来源: Taylor
摘要:
AbstractThe effects of a 24 h dehydration period on plastid ultrastructure and their starch content have been studied on the leafy gametophyte of a poikilohydrous mossPolytrichum formosumHedw. It has been shown that desiccation induces a swift resorption of the starch grains in the plastids of the meristematic cells of the shoot apex without any major disorganisation of the thylakoids. However starch grains are preserved in the dehydrated tissues of the adult leaves. The starch hydrolysis is continued with a marked increase of the sucrose concentration to this may be attributed an osmoregulatory role in the first stages of the water loss. Upon rehydration the plastid ultrastructure is entirely restored with new starch inclusions appearing in less than 4 h.
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