不同光强对美国红栌光合特性的影响

Effects of Light Intensities on Photosynthetic Characteristics of Cotinus coggygria 'Royal purple'

通过测定3种不同光强处理下美国红栌叶片的光合特性,研究了不同光强对彩叶植物光合特性的影响,从而为美国红栌栽培养护提供实践参考。结果表明,在60%,30%光强下,叶片净光合速率日变化呈单峰曲线,最高峰均出现在13:00,峰值分别为4.9,4.04μmol(/m2.s);而对照的净光合速率日变化呈双峰曲线,有明显的"午休"现象,一天中的高峰分别出现在11:00和15:00,峰值分别为4.07,3.88μmol(/m2.s)。研究证实,美国红栌的光抑制效应较为明显,具有一定的耐阴性,因此,在北方栽培美国红栌,可在夏季适当加以遮光保护;但改变光照强度会导致叶色变化,在彩叶植物上应用还需慎重。

This article takes Cotinus cogsygria ＇Royal purple＇ as the material, by determining the leaf photosynthetic characteristic under 3 different light intensity treatments, the effect of different light intensity on color plant photosynthetic characteristic is studied in order to provide theoretcal basis and practical reference for cultivation and conservation. The test result indicates that under 60%, under 30% luminous intensity, the net leaf photosynthesizes rate diurnal variation shows a single-peak curve, and the peak valne appears in 13 o＇clock, in which time peak value is 4.9, 4.04 p^mol/m2＂s respectively. But compared net photosynthesizes rate diurnal variation shows a double-peak curve, with obvious ＂the midday rest＂ phenomenon, and the peak value respectively appears in 11 o＇clock, 15 o＇clock as 4.07, 3.88 p^mol/m2 ＂s. The result shows that： the light inhibitory effect of Cotinus coggygria ＇Royal purple＇ is obvious and it has the characteristic of shade tolerance. Thus, the shading treatment can be taken in summer when it is cultivated in the northern areas. But the application on the color plant should be careful for the reason that the change of light intensity can lead to the change of leaf color.