[Role of water-water circulation in excessive light energy dissipation of ginger leaves].
To investigate the photo-protection of water-water circulation in ginger leaves, the effects of different treatments such as natural light + water control (T1), shading 50% + water control (T2), natural light + 10 mmol x L(-1) IA (T3), shading 50% + 10 mmol x L(-1) IA (T4) on leaf chlorophyll fluorescence parameters, Mehler reaction and the activities of SOD, APX of potted ginger were studied. The results showed that the Pn and Fv/Fm of ginger leaves in T3 and T4 reduced constantly, but that of T1 and T2 had no significant change during treatment. For example, at the ninth day after treatment, the Pn of T3 and T4 decreased by 64% and 33.2% respectively, and the Fv/Fm decreased by 16.5% and 10.9% respectively, while Mehler reaction of T3 and T4 increased by 139.4% and 72.6% respectively, the activity of SOD and APX were significantly higher than those of the controls. At the sixth day after treatment, the leaf Pn and Fv/Fm in all treatments reduced significantly at noon, but Mehler reaction and the activities of SOD and APX increased markedly, and the largest amplitude was observed in T3, followed by T4, and then T1 and T2. So, it was clear that Mehler reaction and the activity of reactive-oxygen scavenging enzymes increased when leaf Pn was inhibited by exogenous IA. The results suggested that water-water circulation played an essential role in dissipating excessive light energy of ginger leaves.
Yong-Zheng
YZ
Zhang
Hai-Dong
HD
Li
Xiu
X
Li
Kun
K
Xu
D020939:Zingiber officinale / Q000502:physiology*; D008027:Light; D010788:Photosynthesis; D018515:Plant Leaves / Q000502:physiology*; D014867:Water
D014867:Water