- 期刊
芭菲爾鞋蘭屬（Paphiopedilum）光飽和點和光補償點之研究
A Study on Light Saturation Point and Light Compensation Point of Paphiopedilum
摘要
本研究以芭菲爾鞋蘭屬（Paphiopedilum）為供試材料，利用可攜帶式光合速率測定儀，量測Paphiopedilum rothschildianum不同葉位、株齡與種間的最大淨光合速率、光飽和點及光補償點。P. rothschildianum以第2葉位的淨光合速率3.10 μmol‧CO2m^-2‧s^-1為最高，並隨著葉位增加而下降，第6葉位的淨光合速率降至0.11 μmol‧CO2‧m^-2‧s^-1為最低。P. rothschildianum、P. tranlienianum及P. callosum均以幼年期淨光合速率最高，分別為2.14 、2.49及1.91μmol‧CO2‧m^-2‧s^-1。芭菲爾鞋蘭三亞屬中以小萼亞屬（Parvisepalum）及短瓣亞屬（Brachypetalum）具有較高之淨光合速率，分別為2.42 ± 0.37及2.83 ± 0.68μmol‧CO2‧m^-2‧s^-1。小萼亞屬、短瓣亞屬及芭菲爾亞屬之光飽和點分別為385 ± 112、353± 64及355 ± 134 μmol‧m^-2‧s^-1，三亞屬間光飽和點之差異未達顯著水準。小萼亞屬、短瓣亞屬及芭菲爾亞屬之光補償點分別為23 ± 12、19 ± 13及33 ± 16 μmol‧m^-2‧s^-1，三亞屬間光補償點之差異未達顯著水準。由結果可知，供試之29種芭菲爾鞋蘭中最高光飽和點為659 μmol‧m^-2‧s^-1，具有最大淨光合速率。因此，在栽培環境中，建議光強度應高於659 μmol‧m^-2‧s^-1，則有利於芭菲爾鞋蘭之生長。
並列摘要
The net photosynthetic rate, light saturation point and light compensation point of different species of Paphiopedilum were investigated in different leaf positions and growing stages, by using a LI-6400 portable photosynthesis system. Results indicated that the maximum net photosynthetic rate was 3.10 μmol‧CO2‧m^-2‧s^-1 in the second leaf position of Paphiopedilum rothschildianum. The photosynthetic rate was decreased with increasing leaf position, with the minimum photosynthetic rate in the 6th leaf position (0.11μmol‧CO2‧m^-2‧s^-1). The photosynthetic rates of P. rothschildianum, P. tranlienianum and P. callosum in juvenile stage were higher than in the ripeness-to–flower stage, in which the rates were 2.14, 2.49, and 1.91 μμmol‧CO2‧m^(-2)‧s^(-1), respectively. The photosynthetic rates of Parvisepalum (2.42 ± 0.37 μmol•CO2•m-2•s-1) and Brachypetalum (2.83 ± 0.68 μμmol‧CO2‧m^-2‧s^-1) were higher than that of Paphiopedilum (1.56μmol‧CO2‧m^(-2)‧s^-1). There was no significant difference in light saturation point among Parvisepalum (385 ± 112μmol‧m^-2‧s^-1), Brachypetalum (353 ± 64μmol‧m^-2‧s^-1), and Paphiopedilum (355 ± 134 μmol‧m^-2‧s^-1). Similarly, there is also no significant difference in light compensation point among them; the values were 23 ± 12, 19 ± 13, and 33 ± 16μmol‧m^-2‧s^-1, respectively. The maximum light saturation point was 659μmol‧m^-2‧s^-1 out of the examined twenty-nine species of Paphiopedilum, suggesting that light intensity of 659μmol‧m^-2‧s^-1 may be the ideal illumination condition for a better growth of Paphiopedilum.