Responses of growth, photosynthesis, and leaf conductance to white light irradiance and end-of-day red and far-red pulses in Fuchsia magellanica Lam.
Responses of growth, photosynthesis, and leaf conductance to white light irradiance and end-of-day red and far-red pulses in Fuchsia magellanica Lam.
复制标题
紫红色的生长、光合作用和叶片电导对白光辐照度以及日终红光和远红脉冲的响应。
DOI：
10.1111/j.1469-8137.1991.tb00010.x
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发表时间：
1991
期刊：
影响因子：
9.4
通讯作者：
A. Di Benedetto
中科院分区：
文献类型：
--
作者：
P. Aphalo;D. Gibson;A. Di Benedetto
结果表明，大花倒挂金钟（Fuchsia magellanica Lam.）- 研究了耐荫的常年-至白色光光子通量密度和一天结束时的红光和远红光照射，以评价不同的形态和功能改变在整个植物对遮荫的适应中所起的作用。在30μmol m-2 s-1的光子通量密度下生长的植物的相对生长率估计是在450μmol m-2 s-1下生长的植物的相对生长率的71%。分配到地上部的总干重的比例在低光植物中较高，但分配到叶片的地上部干重的比例不受任何处理的影响。估算的相对生长速率，比叶面积和叶电导率没有受到影响的一天结束照射。在弱光植物的比叶面积较高，在饱和光子通量密度光合作用是较低的叶面积的基础上，但不是在叶干重的基础上。暗呼吸是较高的高光植物时，表示在面积的基础上，但不表示在干重的基础上。在正常的光周期，在黑暗中测定的叶片导度高的光比在低光的植物，这是一致的，在这些植物中观察到的较高的气孔密度。叶柄的横截面积在弱光下略有减少，尽管单个叶片的面积大幅增加。低光照影响了叶片的显示，降低了叶片厚度，增加了单位干重叶绿素含量。一天结束时的远红导致植物有更多直立的分支。低光子通量密度和远红外都增强了节间的伸长。日终照射的影响在弱光下比在强光下更大，这与在避阴者中观察到的情况相反。平均生长速率的相对较小的差异可以解释的变化，在特定的叶面积，地上部：根干重分配比，光合光响应曲线的形状。然而，当以干重为基础比较光合速率时，弱光植物在强光下似乎并不处于不利地位。
The response of Fuchsia magellanica Lam. - a shade-tolerant perennial - to white light photon flux density and end-of-day red and far-red light irradiation was studied to evaluate the role that different morphological and functional alterations play in whole-plant acclimation to shade. The estimated relative growth rate of plants growing under a photon flux density of 30μmol m2 s1 was 71 % of that of those growing under 450μmol m-2 s-1 . The proportion of total dry weight allocated to shoots was higher in low light plants, but the proportion of shoot dry weight allocated to leaf blades was not affected by any of the treatments. The estimated relative growth rate, specific leaf area and leaf conductance were not affected by end-of-day irradiation. In low light plants the specific leaf area was higher, and at saturating photon flux density photosynthesis was lower on a leaf area basis, but was not on a leaf dry weight basis. Dark respiration was higher in high light plants when expressed on an area basis, but not when expressed on a dry weight basis. During the normal photoperiod, leaf conductance measured in darkness was higher in high light plants than in low light ones, which is consistent with the higher stomatal density observed in these plants. The cross-sectional area of the petioles was slightly reduced in low light in spite of a large increase in the area of individual leaves. Low irradiance affected the display of leaves, decreased leaf thickness and increased chlorophyll content per unit dry weight. End-of-day far-red resulted in plants with more erect branches. Both low photon flux density and far-red enhanced internode elongation. The effect of end-of-day irradiations was bigger in low light than in high light, which is the opposite to what is observed in shade-avoiders. The relatively small difference in mean growth rate can be explained by changes in specific leaf area, shoot: root dry weight partition ratio, and by the shape of the photosynthetic light response curve. However when comparing photosynthetic rates on a dry weight basis low light plants do not seem to be at a disadvantage under high light.