UV-B和NO对玉米幼苗根系呼吸作用的影响

Effects of UV-B and NO on root respiration in maize seedlings

通过对玉米幼苗根系生物量、NO释放量、呼吸作用的分析测定,发现UV-B辐射能够促进根系生物量,却明显地抑制玉米幼苗根系NO的释放、交替呼吸途径活性和细胞色素呼吸途径活性,因而降低了根系的总呼吸量.NO尽管对交替呼吸运行量有抑制作用,但能够明显地促进玉米幼苗根系交替呼吸容量、细胞色素呼吸途径的呼吸容量和运行量以及总呼吸,这可能与玉米幼苗根系相对缺氧时,与根系组织中植物球蛋白协同NO对活性氧(ROS)的生成、清除和转化以及刺激通气组织的形成、供氧条件的改善有关.

The biomasses, rate of NO release and respiration activity were analyzed and determined in the roots of maize seedlings and it was found that radiation of UV-B markedly inhibited the rate of NO-release and respiration activity in roots and increased the biomasses of roots, while NO was able to stimulate the respiration dependent on cytochrome pathway so as to increase the total respiration in roots. The mechanisms were probably due to the improvement of phytoglubin synergy with NO in relation to oxygen supply and detoxification under hypoxia of root tissue, including the elimination and conversion of reactive oxygen species.