Phytochrome-controlled extension growth of Avena sativa L. seedlings
Phytochrome-controlled extension growth of Avena sativa L. seedlings
复制标题
光敏色素控制燕麦幼苗的延伸生长
作者：
E. Schäfer;T. Lassig;P. Schopfer
光诱导抑制黄化苜蓿中胚轴生长和促进胚轴生长的通量率响应曲线。胜利)的发展。辐照时间为24 h，辐照通量为10-6 ~ 105 nmol m-2s-1，辐照波长为563 ~ 1093 nm。主要结论如下：1。两个器官均表现出低通量率反应和高通量率反应。2. 中胚轴对光的反应比胚轴对光的反应更敏感。3. 中胚轴的低通量反应在10-7 nmol m-2s-1（即实验期间的总通量为5·10-2 nmol m-2）为红色，在10-4 nmol m-2s-1 （50 nmol m-2）时达到饱和（约70%的生长抑制）。4. 低通量响应的作用谱与Pr吸收谱相似。讨论了筛选引起的变化。5. 作用谱显示，在约800 nm处，表观光转换截面（Pr→Pfr）呈指数下降。在800 ~ 1093 nm之间，光转换截面对波长的依赖性较弱。6. 高通量响应的作用谱在红色处有一个宽峰，在723 nm处有一个波谷，在740-750 nm处有一个尖峰。
Fluence rate response curves for light-induced inhibition of mesocotyl growth and promotion of coleoptile growth in etiolated Avena sativa L. (cv. Victory) were developed. The irradiation time was 24 h. Fluence rates between 10-6 and 105 nmol m-2s-1 and 30 wavelengths between 563 and 1,093 nm were used. The main conclusions are as follows: 1. Both organs exhibit a low fluence rate response as well as a high fluence rate response. 2. The mesocotyl response is more sensitive to light than the coleoptile response. 3. The low fluence rate response of the mesocotyl shows a threshold of sensitivity at about 10-7 nmol m-2s-1 (i.e., total fluence of 5·10-2 nmol m-2 during the experiment) in the red and a saturation (about 70% inhibition of growth) at 10-4 nmol m-2s-1 (50 nmol m-2). 4. The action spectrum for the low fluence rate response parallels the Pr absorption spectrum. Alterations induced by screening are discussed. 5. The action spectrum demonstrates an exponential decrease in apparent photoconversion cross-section (Pr→Pfr) up to about 800 nm. Between 800 and 1,093 nm the photoconversion cross-section is only weakly dependent on wavelength. 6. The action spectrum for the high fluence rate response shows a broad peak in the red, a trough at 723 nm, and a sharp peak at 740–750 nm.