Effects of Hydrogen Fluoride-stress on Physiological Characteristics of Theaceae Tree Seedlings

In this study, four Theaceae tree species were processed by setting up two hydrogen fluoride concentration gradient (including controls), the actual quantum yield (Y (II)) of PSII, the relative electron transport rate (ETR), non-regulatory energy dissipation quantum yield (Y(NO)), regulatory energy dissipation quantum yield (Y(NPQ)), non-photochemical quenching coefficient (NPQ) and the relative electrical conductivity and other physiological characteristic value were measured, and fuzzy membership function method was applied for comprehensive evaluation and stress resistance sequencing of these four species, which could help to explore the impact of HF-stress on physiological indicators of Theacea tree seedlings, and effectively screen out tress species with high resistance to hydrogen fluoride; besides, it could provide the basis for selection of planting trees with the purpose of environmental protection, and also provide a reference for HF stress mechanisms study. This study showed that, under the circumstance of 500 ppm hydrogen fluoride stress, chlorophyll fluorescence indicator of Theaceae tree species presented a downward trend on the whole, which concretely embodied in varying degrees of decline of Y (II) of PSII, ETR, Y (NO), Y (NPQ), NPQ. And the cell membranes of trees species were damaged and the membrane permeability increased. Except for Schima superba, the relative conductivity value of other species showed an upward trend. The capacity of these four species in anti-hydrogen fluoride contamination was Tutcheria championi first, Camellia oleifera second, Schima superba third, Gordonia axillaries is the last.