桶柑葉片光合作用特徵之研究

Studies on Photosynthetic Characteristics of Tankan (Citrus tankan Hay.) Leaves

張哲嘉(Jer-Chia Chang) ； 林宗賢(Tzong-Shyan Lin)

《中國園藝》 41卷3期 (1995/09) Pp. 161-173

https://doi.org/10.6964/JCSHS.199509.0161

摘要

本試驗探討多項因子對桶柑淨光合作用速率的影響，以期對桶柑光合成能力有進一步認識。以可控制環境因子的開放式光合作用測定系統，測得溫室栽培盆株葉片之暗呼吸速率爲1.0μmol/平方公尺•s，光補償點20-40Μe/平方公尺•s，光量子産量(quantum yield; Φ) 0.025μmol CO2/μmol PPFD，而在光度400-500μE/平方公尺•s以上、葉溫29-34℃間、蒸氣壓差1.20KPa之內時擁有較大光合成能力，約6-7μmol/平方公尺•s。
以LI-6200可攜式光合作用測定系統調查田間植株葉片光合成能力，光合成能力之日變化趨勢約在上午八時達到最高，爲11.0-12.0μmol/平方公尺•s，午間有下降現象，氯孔導度則在上午七時最高，爲0.30mol/平方公尺•s；不論枝條屬性，當年生葉片光合成能力遠大於上年生葉片，顯示當年生葉片爲果實生長之主要供源，但當年生不同葉齡營養枝葉片間光合成能力沒有差異。

關鍵字

桶柑 ； 淨光合用速率 ； 光合作用

並列摘要

Some factors affecting the net photosynthetic rates (Pn) of Tankan leaves were investigated. Pn values of glass-house grown potted plants were measured in an open gas analysis system under controlled environmental conditions. At 28℃ the dark respiration rate was 1.0μ mol/m^2•s, quantum yield (Φ) was 0.025μ mol CO2/μ mol PPFD. The maximum Pn value, 60.-7.0μ mol/m^2•s, occurred at PPFD above 400-500μ E/m^2•s, leaf temperature between 29-34℃, and vapor pressure deficit (VPD) less than 1.2KPa.
Diurnal changes of field-grown trees were measured in a LI-6200 portable photosynthesis system. The maximum Pn value, 11-12μ mol/m^2•s, occurred at 7:00 LST. The Pn values of the leaves with different ages on current shoots were not significantly different, but were siginificantly higher than those on one-year old shoots. The results suggest that assimilate supply to the growing fruits were mainly derived from the current-year leaves.

並列關鍵字

Tankan Citrus tankan Hay. ； net photosynthetic rate ； photosynthesis