[Relationship between endogenous active oxygen species, ethylene and the development and operation of the alternative pathway in tobacco callus under salt stress].
This paper reported firstly the dynamic changes of the alternative pathway and the cytochrome pathway in tobacco callus under different concentration of salt. The production rate of endogenous ethylene, the contents of active oxygen species (O2-., .OH and H2O2) and the activities of related enzyme (SOD and CAT) were also investigated simultaneously. The results indicated that the actual operation of the alternative pathway (rho Valt) increased gradually and reached the maxima at 0.75% salt concentration, then declined, while the capacity of the alternative pathway (Valt) didn't exhibit the same change pattern with rho Valt and the cytochrome pathway (rho' Vcyt) changed contrary to rho Valt. At the same time, H2O2 and O2-. accumulated rapidly and reached their peak value at about 0.5% and 0.75% salt concentration respectively, while the content of .OH increased consistently. The production rate of endogenous ethylene increased rapidly and reached its maxima at about 0.5% salt concentration. These data demonstrated that changes of Valt in tobacco callus were associated with a parallel production of H2O2 and endogenous ethylene and a opposite production of .OH, while rho Valt changed parally with the production of O2-.. On the basis of above results, it was deduced that the changes of the development and operation of the alternative pathway in tobacco callus under salt stress might be correlated with the production of endogenous ethylene and the active oxygen species. The possible participation of the alternative pathway in response to salt stress was also discussed.
Zhou
G K
GK
State Key Laboratory of Arid Agroecology, Lanzhou University, Lanzhou 73000.
Liang
H G
HG
D003580:Cytochromes / Q000378:metabolism; D005030:Ethylenes / Q000378:metabolism*; D017382:Reactive Oxygen Species / Q000378:metabolism*; D012965:Sodium Chloride / Q000494:pharmacology*; D014026:Nicotiana / Q000378:metabolism* / Q000502:physiology
D003580:Cytochromes; D005030:Ethylenes; D017382:Reactive Oxygen Species; D012965:Sodium Chloride; C036216:ethylene