%A WANG Tian, WANG Suping, GUO Shirong, SUN Yanjun
%T Effects of exogenous spermidine on the photosynthesis
of L. seedlings
under rhizosphere hypoxia stress
%0 Journal Article
%D 2008
%J Front. Agric. China
%J Frontiers of Agriculture in China
%@ 1673-7334
%R 10.1007/s11703-008-0015-5
%P 55-60
%V 2
%N 1
%U {https://journal.hep.com.cn/fag/EN/10.1007/s11703-008-0015-5
%8 2008-03-05
%X With water culture, this paper studied the effects of exogenous spermidine (Spd) on the net photosynthetic rate (Pn), intercellular CO2 concentrations (Ci), stomatal conductance (Gs), transpiration rate (Tr), apparent quantum yield (?c), and carboxylation efficiency (CE) of cucumber seedlings under hypoxia stress. The results showed that Pn decreased gradually under the hypoxia stress, and reached the minimum 10 days later, which was 63.33% of the control. Compared with that of the hypoxia-stressed plants, the Pn 10 days after the application of exogenous Spd increased by 1.25 times. A negative correlation (R2 = 0.473–0.7118) was found between Pn and Ci, and Gs and Tr changed in wider ranges, which decreased under the hypoxia-stress, but increased under the hypoxia-stress plus exogenous Spd application. There was a significant positive correlation between Gs and Tr (R2 = 0.7821–0.9458), but these two parameters had no significant correlation with Pn. The hypoxia stress induced a decrease of ?c and CE by 63.01% and 72.33%, respectively, while the hypoxia stress plus exogenous Spd application made ?c and CE increase by 23% and 14%, respectively. The photo-inhibition of cucumber seedlings under hypoxia stress was mainly caused by non-stomatal inhibition, while the exogenous Spd alleviating the hypoxia stress by repairing photosynthesis systems.