能量对香石竹切花在瓶插期间呼吸电子途径的影响

Effect of Energy Supply on Respiratory Electron Transport Pathways during Vase Holding of Cut Carnation Flowers

摘要:

采用外加0.1 mmol/L ATP或0.5 mmol/L二硝基苯酚(DNP)的方法，研究了香石竹(Dianthus caryophyllus L.)切花在25?1℃和80%~90%相对湿度下瓶插期间呼吸电子传递途径的变化情况。结果表明，香石竹切花在瓶插7 d时的呼吸速率达到高峰；ATP处理明显加快切花的呼吸速率，在瓶插7 d时呼吸速率高峰值较对照(未用ATP处理)升高1倍。细胞色素途径与总呼吸活性存在显著正相关。细胞色素途径占总呼吸的比重在切花瓶插4 d后上升，并且线粒体电子传递主要依靠细胞色素主路途径进行。经ATP处理后香石竹切花的交替呼吸途径的容量、实际运行活性和运行系数明显增加；交替呼吸途径占总呼吸活性比重在瓶插4 d后迅速上升，并且交替呼吸途径容量与总呼吸活性存在显著正相关。而DNP处理则降低交替呼吸途径容量。这说明外源ATP处理加强了香石竹切花在整个瓶插期间的呼吸作用，增加了呼吸速率的高峰值，提高了抗氰呼吸作用。

Abstract:

To well understand the role of energy in respiratory electron transport pathways during senescence of plant tissues, cut carnation flowers were treated with 0.1 mmol/L ATP or 0.5 mmol/L dinotrophenol (DNP) and then held at 25?1?C and 80%~90% relative humidity. A climacteric peak of respiration rate appeared at the 7th day of vase life. ATP treatment enhanced the respiration rate. Furthermore, a linear relationship existed between cytochrome respiration and total respiration. The contribution from the cytochrome respiration pathway to the total respiration increased after 4 days of vase holding, which indicated that the electron transport depended mainly on the cytochrome respiration pathway. Treatment with ATP increased the capacity, operative activity and operation coefficient of the alternative respiration pathway, and the ratio of the alternative respiration pathway to the total respiration increased after 4 days of vase holding with a significant linear relationship between the alternative respiration pathway capacity and the total respiration. DNP treatment reduced the alternative respiration pathway capacity. These results suggested that the addition of ATP to vase solution enhanced total respiration throughout the whole vase holding and increased the alternative respiration pathway capacity.