Alleviation of photoinhibition in drought-stressed wheat (Triticum aestivum) by foliar-applied glycinebetaine.
Effects of foliar application of 100 mmol/L glycinebetaine (GB) on PS II photochemistry in wheat (Triticum aestivum) flag leaves under drought stress combined with high irradiance were investigated. The results show that GB-treated plants maintained a higher net photosynthetic rate during drought stress than non-GB treated plants. Exogenous GB can preserve the photochemical activity of PSII, for GB-treated plants maintain higher maximal photochemistry efficiency of PSII (F(v)/F(m)) and recover more rapidly from photoinhibition. In addition, GB-treated plants can maintain higher anti-oxidative enzyme activities and suffer less oxidative stress. Our data suggest that GB may protect the PSII complex from damage through accelerating D1 protein turnover and maintaining anti-oxidative enzyme activities at higher level to alleviate photodamage. Diethyldithiocarbamate as well as streptomycin treatment can impair the protective effect of GB on PSII. In summary, GB can enhance the photoinhibition tolerance of PSII.
Ma
Qian-Quan
QQ
Tropical Crops Genetic Resources Institute, Chinese Academy of Tropical Agricultural Sciences, Baodao Xincun, Danzhou, Hainan 571737, PR China.
Wang
Wei
W
Li
Yong-Hua
YH
Li
De-Quan
DQ
Zou
Qi
Q
D000975:Antioxidants / Q000378:metabolism; D001622:Betaine / Q000378:metabolism / Q000494:pharmacology*; D002245:Carbon Dioxide / Q000378:metabolism; D002734:Chlorophyll / Q000378:metabolism; D010788:Photosynthesis / Q000187:drug effects* / Q000502:physiology; D045332:Photosystem II Protein Complex / Q000037:antagonists & inhibitors / Q000378:metabolism; D013482:Superoxide Dismutase / Q000037:antagonists & inhibitors / Q000378:metabolism; D014908:Triticum / Q000187:drug effects* / Q000502:physiology / Q000528:radiation effects; D014867:Water / Q000502:physiology*
D000975:Antioxidants; D045332:Photosystem II Protein Complex; D014867:Water; D002734:Chlorophyll; D002245:Carbon Dioxide; D001622:Betaine; D013482:Superoxide Dismutase