Please use this identifier to cite or link to this item: http://hdl.handle.net/11455/20916
標題: 低溫處理對番木瓜葉片之生理影響
Effects of Low Temperature on the Physiological Metabolism of Papaya (Carica papaya L.)Leaves
作者: 劉秋麗
Liou, Chiou-Lih
關鍵字: 光合成速率;photosynthetic rate;呼吸速率;抗氧化酵素;番木瓜;低溫逆境;papaya;superoxide dismutase;glutathione reductase;monodehydroascorbate reductase;dehydroascorbate reductase
出版社: 植物學系
摘要: 
以四種溫度25,20,15,10度處理番木瓜(Carica papaya L.Tainung
No.50植株,結果發現 10 度處理之植株生長明顯減緩,葉片之光合成速率
及呼吸速率均受低溫抑制,上述抑制情形, 以10度處理之番木瓜較為嚴重.
低溫逆境時,葉片中可溶糖及脯胺酸含量明顯增加,二者已知可當作滲透保
護劑.利用高效液相層析法(HPLC)分析主要可溶糖含量,發現果糖,葡萄糖,
蔗糖及麥芽糖等四種糖含量皆增加,其中以蔗糖含量最多,且增加量亦最
多,另外,分析游離胺基酸發現除了脯胺酸外,幾種主要胺基酸天門冬胺酸,
麩胺酸,絲胺酸含量隨處理溫度下降而減少,尤以10度處理時,會隨處理天
數增加而減少. 在低溫逆境下,番木瓜葉片之抗氧化酵素 SOD(
superoxide dismutase),APX(ascorbateperoxidase)及GR(glutathione
reductase)活性並無增加,在15度處理幾乎無DHAR(dehydro-ascorbate
reductase)活性,但MDHAR(monodehydroascorbate reductase)活性增加,
在10度處理時有較高之MDHAR 及 DHAR 活性,顯示番木瓜在低溫逆境時,不
僅光合成作用受抑制,同時也誘導氧化逆境發生.

The 45-d-old papaya(Carica papaya L. tainung No.5) plants
were grown ingrowth chambers at constant temperature of 25,20,15
and 10 degree for 5 days.When exposed to 15 and 10 degree,plant
growth was arrested. Further analysis of photosynthesis and dark
respiration rate of papaya leaves indicated thatboth process
were inhibited under low temperature of 15 degree and 10
degreewith higher degree of inhibition at 10 degree treatment.
Total soluble sugar and proline contents of papaya leaves under
10 degreewere increased. Both sugar and proline have been shown
to serve as compatible solutes which have been known involved in
the mechanism of stress tolerance.Analysis of constituents of
total soluble sugars with HPLC indicated thatcontents of
fructose, glucose, sucrose and maltose were all increased under
15degree and 10 degree treatment. Among them, sucrose content
was the highest.Nevertheless, analysis of consituents of amino
acids, except proline the contentof major amino acids including
aspartate, glutamate and serine were decreasedunder 10 degree.
The activities of superoxide dismutase, ascorbate peroxidase and
glutathionereductase did not increase in response to low
temperature. A higher monodehydro-ascorbate reductase activity
was observed under 15 degree. An active dehydroas-corebate
reductase was not found under 15 degree treatment but could be
easy quatified in leaved of 10 degree treatment. The results
suggested that expossureof papaya, a tropical origin plant, to
low nonfreezing temperature might causeoxidative stress to the
plants.
URI: http://hdl.handle.net/11455/20916
Appears in Collections:生命科學系所

Show full item record
 

Google ScholarTM

Check


Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.