title: [Photosynthetic parameters and chlorophyll fluorescence characteristics of Pleioblastus kongosanensis f. aureostriaus under drought stress].
abstract: A pot experiment was conducted to study the variations of Pleioblastus kongosanensis f. aureostriaus plant morphology, leaf water content (LWC) , leaf water potential (LWP) , photosynthetic parameters, chlorophyll fluorescence parameters, and soil water content (SWC) under natural drought stress, as well as the relationships between these variations and environmental factors. On the 17th day under the stress, the P. kongosanensis presented damaged symptom. Its leaves dehydrated, drooped, and wrap-formed. On the 43rd day, the aboveground part of the plant died from dehydration. When the plant was re-watered for 10 days, the chlorophyll fluorescence parameters had no significant differences with those on the 43rd day under the stress. The SWC decreased significantly in 0-21 d of the stress, and the LWP and LWC dropped rapidly and significantly after 17 d and 29 d, respectively. With the increase of drought stress, the leaf transpiration rate (Tr) and stomatal conductance (g(s)) had a persistent decline, photosynthetic rate (Pn) had a greater fluctuation, and instantaneous water use efficiency (PWUE) decreased after an initial increase. After 17 d drought stress, the limiting factor of Pn was from stomatal to non-stomatal, and the actual photosynthetic efficiency (phiPS II) declined significantly; after 25 d, the photosynthetic organ was damaged, and the maximum photochemical efficiency of PS II (Fv/Fm) and non-photochemical quenching (qN) changed significantly from 0.64 to -0.11 and from 0.79 to 0.33, respectively. The Tr, g(s), and PWUE had close correlations with LWP; the Pn, Tr, and g(s) were sensitive to air relative humidity (RH); and the gs was the main factor causing the diurnal variations of photosynthetic parameters. It was suggested that P. kongosanensis could grow well on the soil with relative moisture content > or = 12% and drought duration less than 25 d.
authors.affiliation: State Forestry Administration Key Laboratory of Bamboo and Rattan Science and Technology, International Centre for Bamboo and Rattan, Beijing, China. ljgx2003@126.com
authors.forename: Juan
authors.initials: J
authors.lastname: Li
authors.forename: Zhen-Hua
authors.initials: ZH
authors.lastname: Peng
authors.forename: Jian
authors.initials: J
authors.lastname: Gao
authors.forename: Yuan-Wen
authors.initials: YW
authors.lastname: Chen
mesh_terms: D031723:Bambusa / Q000502:physiology*; D002734:Chlorophyll / Q000378:metabolism*; D055864:Droughts; D005453:Fluorescence; D010788:Photosynthesis / Q000502:physiology*; D013312:Stress, Physiological
chemical_list: D002734:Chlorophyll