Please use this identifier to cite or link to this item:
標題: 根溫處理對葉萵苣生理之影響
Effect of Root-zone Temperature on the Physiology of Leaf Lettuce (Lactuca sativa L.)
作者: 莊乃穎
Juang, Nae Yiing
關鍵字: Lettuce;萵苣;Root-zone temperature;Electrolyte leakage;Water potential;Peroxidase;根圈溫度;電解質滲漏;水分潛勢;過氧化酵素
出版社: 園藝學系
試驗以涼季蔬菜之萵苣葉片為材料,經 50℃水浴5至60分鐘。測定17種萵
25℃、30℃ 及 35℃ 之根溫處理 12 天,探討其生長與生理之變化。
和根部鮮重及乾重於 25℃、30℃ 根溫處理間,大多無顯著差異;35℃時
此二品系的生長量明顯較 25℃ 或 30℃ 者為低。30℃ 高根溫下白粉品
在生理測試方面,二品系根溫處理第 6天、12天之光合作用及之水分潛勢
,於35℃時均顯著低於 25℃、30℃。35℃ 根溫下,地上部及根部之呼吸

The thermostability of leaf-tissue membrane of seventen
lettuce cultivars grown in a greenhouse was assessed by
measuring electrolyte leakage of the tissue for specific
intervals during a 60 minute period at 50℃ . Results
indicated that the differential responses among cultivars,
exhibited at 50℃ for 10 minutes , were most significant and
were selected for the subsequent
assessment of leaf-tissue heat injury.Among the cultivars
tested , Improved Green Leaf (IGL) was found to be the most heat
tolerant while White Power (WP) was the most heat
sensitive . Two cultivars of lettuce , IGL and WP, were used to
investigate the physiological changes and growth rates in
solution at 25, 30, and 35℃. Results showed that the growth
of both shoot and root were reduced by supraoptimal
temperature of 35℃. The growth inhibition were more pronounced
on WP than IGL at 35℃ root-zone temperature. The
photosynthetic rate and water potential of the leaves were
found to decrease with rising root-zone temperature up to 35℃.
No significant differences in chlorophyll levels were observed
among treatments. Increasing root temperature resulted in
higher respiration rate and activity of roots . The
respiration rate and activity of excised root were markedly
enhanced as the root-zone temperature was raised to 35℃ and
thus leading to more carbohydrate consumption in the root.
This, in turn ,increased the export of sugar from shoot, and
soluble carbohydrate accumulated in the root.
The contents of free amino acids, the activity of peroxidase
and the production of ethylene were increased significantly by
exposing to 35℃ root-ozone temperature. The result indicated
that the supraoptimal root temperature may induced the root
senescence leading to inhibition of shoot growth.
Appears in Collections:園藝學系

Show full item record

Google ScholarTM


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