Wang J.-H.,Yunnan Academy of Agricultural Sciences |
Wang J.-H.,Key Laboratory of Yunnan Flower Breeding |
Li S.-C.,Yunnan Academy of Agricultural Sciences |
Li S.-C.,Key Laboratory of Yunnan Flower Breeding |
And 9 more authors.
Physiologia Plantarum | Year: 2013
Cyclic electron flow (CEF) plays an important role in photoprotection for angiosperms under environmental stresses. However, ferns are more sensitive to drought and their water transport systems are not as efficient as those of angiosperms, it is unclear whether CEF also contributes to photoprotection in these plants. Using Microsorum punctatum and Paraleptochillus decurrens, we studied the electron fluxes through both photosystem I (PSI) and photosystem II (PSII) under water stress and their leaf anatomies. Our goal was to determine if CEF functions in the photoprotection of these ferns and, if so, whether CEF stimulation is related to leaf anatomy. Compared with P. decurrens, M. punctatum had thicker leaves and cuticles and higher water storage capacity, but lower stomatal density and slower rate of water loss. During induced drought, the decrease in leaf water potential (Ψleaf) was more pronounced in P. decurrens than in M. punctatum. For both species, the decline in Ψleaf was associated with a lower effective PSII quantum yield, photochemical quantum yield of PSI and electron transport rate (ETR), whereas increases were found in the quantum yield of regulated energy dissipation, CEF and CEF/ETR(II) ratio. Values for CEF and the CEF/ETR(II) ratio peaked in M. punctatum at a light intensity of 500-600 μmol m-2 s-1 vs only 150-200 μmol m-2 s-1 in P. decurrens. Therefore, our results indicate that the stimulation of CEF in tropical ferns contributes to their photoprotection under water stress, and is related to their respective drought tolerance and leaf anatomy. © Physiologia Plantarum 2012.
Li H.,Yunnan University |
Li H.,Yunnan Academy of Agricultural Sciences |
Li H.,National Engineering Research Center for Ornamental Horticulture |
Li H.,Key Laboratory of Yunnan Flower Breeding |
And 16 more authors.
Mitochondrial DNA | Year: 2014
The complete nucleotide sequence of the sugar beet (Beta vulgaris ssp. vulgaris) chloroplast genome (cpDNA) was determined in this study. The cpDNA was 149,637 bp in length, containing a pair of 24,439 bp inverted repeat regions (IR), which were separated by small and large single copy regions (SSC and LSC) of 17,701 and 83,057 bp, respectively. 53.4% of the sugar beet cpDNA consisted of gene coding regions (protein coding and RNA genes). The gene content and relative positions of 113 individual genes (79 protein encoding genes, 30 tRNA genes, 4 rRNA genes) were almost identical to those of tabacoo cpDNA. The overall AT contents of the sugar beet cpDNA were 63.6% and in the LSC, SSC and IR regions were 65.9%, 70.8% and 57.8%, respectively. Fifteen genes contained one intron, while three genes had two introns. © 2014 Informa UK Ltd.