摘要
在25℃,光合光量子流通量0.35m mlo·m^(-2)·S^(-1)下,香荚兰叶片的需 CO_2的释氧速率为1.59μmol O2·m^(-2)·S^(-1)。间歇暗期1分钟,照光叶片需 CO_2释氧速率能提高32.7%。叶片需CO_2释氧速率以25℃时为最高。温度升高至30和34℃时,叶片需 CO_2释氧速率降低。在4℃下8小时或10小时,香荚兰叶片的需 CO_2释氧速率和呼吸速率均有下降,但幅度较小。表明香荚兰能耐短期零上低温。在较高光强(0.9 m mol·m^(-2)·S^(-1)光量子)下0.5或1小时,叶片表现不同程度的光抑制现象。香荚兰的茎含有叶绿素 a 和叶绿素 b,a/b 为1.13,较叶片低。茎组织的丙酮提取液的吸收光谱表现胡萝卜素和叶黄素的吸收需 CO_2的释氧速率为2.86μmolO_(2·g) 鲜重^(-1)·h^(-1),相当叶片的92.5%。表明茎是香荚兰光合作用组织的一部分。
The rate of CO_2—dependent oxygen evolution,measured at 25℃ and in photosyn-
thetic photon flux density with 0.35m tool.m^(-2)·s^(-1),was 1.59μ mol O_2·m^(-2)·s^(-1)
for leaves of Vanilla fragrans.The rate of oxygen evolution declined with increasing
temperature from 25℃ to 30℃ or 34℃,but maximum rate of respiration was found
at 30℃ or 34℃.The rate of oxygen evolution also decreased when leaves were
pre—exposed to 4℃ for 8 or 10 h.Higher rate of CO_2—dependent oxygen evolution
was found when leaves were pre—irradiated for 1 min in photosynthetic photon flux
density with 0.9 m mol·m^(-2)·s^(-1)and a following dark period for 1 min,but the
photoinhibition was also found in Vanilla leaves as the duration of pre—irradiation was
prolonged.
The shoot of Vanilla fragrans contained chlorophyll a and chlorophyll b and the
ratio value of a/b was 1.13.The absorbance spectrum of the shoot extract showed
that it contained carotin and xanthophyll.The presence of these pigments might
benefit the shoot to absorb the irradiated energy.The rate of CO_2-dependent oxygen
evolution for shoot was 92.5% of that for leaves.
出处
《热带作物学报》
CSCD
1990年第1期103-106,共4页
Chinese Journal of Tropical Crops
关键词
香荚兰
光合特性
Vanilla fragrans
CO_2-dependent oxygen evolution
light
temperature
