Chlorophyll fluorescence and CO(2) assimilation of black spruce seedlings following frost in different temperature and light conditions.
Chlorophyll fluorescence and CO(2) assimilation of black spruce seedlings following frost in different temperature and light conditions.
复制标题
DOI：
10.1093/treephys/20.4.249
复制
发表时间：
2000-03
期刊：
影响因子：
4
通讯作者：
M. Lamontagne;F. Bigras;H. Margolis
中科院分区：
文献类型：
--
作者：
M. Lamontagne;F. Bigras;H. Margolis
以1年生黑云杉（Picea mariana（Mill.））幼苗叶片为材料，研究了人工霜冻对叶片光饱和光合速率（A（max））、地面、最大和可变荧光参数（F（o）、F（m）、F（v）和F（v）/F（m））的影响。BSP）生长在高（25摄氏度），中（15摄氏度）和低（5摄氏度）的温度和中等（240摩尔米（-2）秒（-1））和低（80摩尔米（-2）秒（-1））的辐照。1年生叶片的光抑制是更大的幼苗生长在中等光比幼苗生长在低光。在两种辐照度下，随着生长室温度的降低，光抑制增加。F（v）/F（m）的变化主要由F（v）的变化引起。与对照值相比，暴露于-4 ℃降低了F（v）/F（m）和A（max）。-4 ℃霜冻处理的效果在弱光下生长的幼苗中比在中等光下生长的幼苗中更大，这可能是因为在霜冻处理之前在中等光下生长的幼苗已经部分地受到光抑制。在-4 ℃处理后，在弱光下生长的幼苗中，F（v）/F（m）和A（max）都没有恢复。光饱和光合作用随生长室温度的降低而降低。在25 ℃下生长的幼苗比在15 ℃和5 ℃下生长的幼苗，光饱和光合作用对-3 ℃和-4 ℃霜冻处理更敏感。在15 ℃下生长的幼苗的A（max）仅对-4 ℃的霜冻处理敏感，而在5 ℃下生长的幼苗的A（max）对任何霜冻处理都不敏感。恢复A（最大）霜冻后，在高温下生长的幼苗比在低温下生长的幼苗需要更长的时间。对于在相同温度但不同光照下生长的幼苗，A（max）和F（v）/F（m）反映了中度霜冻对光合系统的损害。然而，对于生长在相同的光照，但不同的温度下，幼苗，A（最大）提供了一个更敏感的指标霜冻损害的光合系统比F（v）/F（m）的比例。
Effects of artificial frosts on light-saturated photosynthesis (A(max)) and ground, maximal and variable fluorescence variables (F(o), F(m), and F(v) and F(v)/F(m)) were monitored on 1-year-old foliage of black spruce seedlings (Picea mariana (Mill.) BSP) grown at high (25 degrees C), moderate (15 degrees C) and low (5 degrees C) temperatures and moderate (240 mol m(-2) s(-1)) and low (80 mol m(-2) s(-1)) irradiances. Photoinhibition of 1-year-old foliage was greater in seedlings grown in moderate light than in seedlings grown in low light. Photoinhibition increased with decreasing growth chamber temperature at both irradiances. Most changes in F(v)/F(m) were caused by changes in F(v). Exposure to -4 degrees C decreased both F(v)/F(m) and A(max) compared with control values. The effect of the -4 degrees C frost treatment was greater in seedlings grown in low light than in seedlings grown in moderate light, probably because seedlings grown in moderate light were already partially photoinhibited before the frost treatment. Following -4 degrees C treatment, neither F(v)/F(m) nor A(max) recovered in seedlings grown in low light. Light-saturated photosynthesis decreased with decreasing growth chamber temperature. Light-saturated photosynthesis was more sensitive to the -3 and -4 degrees C frost treatments in seedlings grown at 25 degrees C than in seedlings grown at 15 and 5 degrees C. The A(max) of seedlings grown at 15 degrees C was sensitive only to the -4 degrees C frost treatment, whereas A(max) of seedlings grown at 5 degrees C was not sensitive to any of the frost treatments. Recovery of A(max) following frost took longer in seedlings grown at high temperatures than in seedlings grown at low temperatures. For seedlings grown at the same temperature but under different irradiances, both A(max) and F(v)/F(m) reflected damage to the photosynthetic system following a moderate frost. However, for seedlings grown at the same irradiance but different temperatures, A(max) provided a more sensitive indicator of frost damage to the photosynthetic system than F(v)/F(m) ratio.