Liu Y.F.,ShenYang Agricultural University |
Liu Y.F.,Key Laboratory of Protected Horticulture of Ministry of Education |
Liu Y.F.,Key Laboratory of Protected Horticulture of Liaoning Province |
Qi M.F.,ShenYang Agricultural University |
And 5 more authors.
Plant Science | Year: 2012
The effects of low night temperature (LNT, i.e., 9 and 6°C) stress and rewarming (15°C night temperature) on the photosynthesis, photosystems I and II (PSI and PSII), and antioxidant system of tomato leaves were studied. The results showed that 9 d of LNT treatment led to an irreversible reduction in the photosynthetic rate. This reduction was accompanied by stomatal limitation of CO2 supply and significant decline in ribulose-1,5-bisphosphate carboxylase/oxygenase activity at the transcription level, as well as sucrose accumulation. LNT treatment induced the reversible photoinhibition of PSII, decreased PSII activity, increased the photochemical yield of PSI Y(I), and markedly caused the acceptor side limitation of PSI. This finding was reflected by the higher value of Y(NA) in the treated plants than in the control. At the same time, a downregulation of electron transport for photosynthetic carbon reduction under LNT was mostly compensated by Ja(O2-dependent) driven by the water-water cycle. © 2012.
Liu Y.-F.,ShenYang Agricultural University |
Liu Y.-F.,Key Laboratory of Protected Horticulture of Ministry of Education |
Liu Y.-F.,Key Laboratory of Protected Horticulture of Liaoning Province |
Zhang G.-X.,ShenYang Agricultural University |
And 8 more authors.
Journal of Plant Growth Regulation | Year: 2015
The effect of exogenous CaCl2 on photosynthesis, antioxidant system, and chloroplast ultrastructure of tomato leaves under low night temperature (LNT) was investigated. Tomato seedlings were pretreated with 27 mM CaCl2, 5 mM EGTA, respectively, for 4 days and then exposed to LNT treatment at 6 °C for 7 days. Plants treated with CaCl2 showed higher photosynthesis, increased stomatal aperture and chloroplast area, and decreased number of starch grains under LNT stress than those treated with distilled water. LNT increased the contents of superoxide radicals, hydrogen peroxide, and malondialdehyde, whereas calcium application reduced the contents of these compounds. The increase in antioxidant activities caused by LNT stress was also enhanced by the application of exogenous calcium. The opposite effects were observed with ethylene glycol-bis-(2-aminoethyl) tetraacetic acid pretreatment. CaCl2 application improved photosynthesis in LNT-stressed plants. Such improvement was associated with increased stomatal conductance, improved antioxidant activities, and adjusted chloroplast structure. These results suggest that CaCl2 application improved photosynthesis in LNT-stressed plants. It provided fundamental information for further molecular mechanism research. © 2014, Springer Science+Business Media New York.
Zhang G.,ShenYang Agricultural University |
Zhang G.,Key Laboratory of Protected Horticulture of Ministry of Education |
Zhang G.,Key Laboratory of Protected Horticulture of Liaoning Province |
Liu Y.,ShenYang Agricultural University |
And 14 more authors.
PLoS ONE | Year: 2014
The effect of exogenous CaCl2 on photosystem I and II (PSI and PSII) activities, cyclic electron flow (CEF), and proton motive force of tomato leaves under low night temperature (LNT) was investigated. LNT stress decreased the net photosynthetic rate (Pn), effective quantum yield of PSII [Y(II)], and photochemical quenching (qP), whereas CaCl2 pretreatment improved Pn, Y(II), and qP under LNT stress. LNT stress significantly increased the non-regulatory quantum yield of energy dissipation [Y(NO)], whereas CaCl 2 alleviated this increase. Exogenous Ca2+ enhanced stimulation of CEF by LNT stress. Inhibition of oxidized PQ pools caused by LNT stress was alleviated by CaCl2 pretreatment. LNT stress reduced zeaxanthin formation and ATPase activity, but CaCl2 pretreatment reversed both of these effects. LNT stress caused excess formation of a proton gradient across the thylakoid membrane, whereas CaCl2 pretreatment decreased the said factor under LNT. Thus, our results showed that photoinhibition of LNT-stressed plants could be alleviated by CaCl2 pretreatment. Our findings further revealed that this alleviation was mediated in part by improvements in carbon fixation capacity, PQ pools, linear and cyclic electron transports, xanthophyll cycles, and ATPase activity. © 2014 Zhang et al.
Liu X.,ShenYang Agricultural University |
Liu X.,Key Laboratory of Protected Horticulture of Ministry of Education |
Liu X.,Key Laboratory of Protected Horticulture of Liaoning Province |
Xu T.,ShenYang Agricultural University |
And 23 more authors.
Acta Physiologiae Plantarum | Year: 2016
Phytohormones, such as auxin (IAA) and gibberellin (GA), are known to be essential for fruit development. We utilized GA-deficient (gib-3) and diageotropica (dgt) tomato mutants to elucidate the effects of single hormones in the pericarp. The application of IAA or GA, respectively, to gib-3 or dgt single mutants induced a significant morphological difference in the fruit set. We found that IAA application induced cell division in the gib-3 pericarp and that GA application did not increase the cell layers in the dgt pericarp. In molecular studies, the expression levels of SlARF6, SlARF8, SlARF10 and SlARF16 were downregulated by IAA application, whereas the expression of their regulators miRNA160 and miRNA167 was upregulated by IAA application in gib-3 plants. Furthermore, the expression levels of SlARF6, SlARF8, SlARF10 and SlARF16 were upregulated by GA application, whereas the expression levels of miRNAs were reduced in the dgt mutant. These results imply that the expression levels of SlARF6, SlARF8, SlARF10 and SlARF16 were negatively correlated with the number of cell layers in the pericarp during fruit set. To further support this hypothesis, 35s:mSlARF10 transgenic plants resistant to SlmiR160 cleavage of SlARF10 mRNA were used to investigate the cell layers in fruit. These results revealed that mSlARF10 overexpression indeed resulted in fewer cell layers than in wild type fruit. Together, our data suggest that GA- and IAA-mediated miRNAs and their target ARFs influence the formation of pericarp cell layers during fruit set development. © 2016, Franciszek Górski Institute of Plant Physiology, Polish Academy of Sciences, Kraków.