Responses of Microstructure, Ultrastructure and Antioxidant Enzyme Activity to PEG-Induced Drought Stress in Cyclocarya paliurus Seedlings

Drought is one of the most important abiotic constraints on agricultural productivity, while global warming leads to occurrence more frequent drought events. Cyclocarya paliurus a multiple-function tree species with medicinal value and timber production, but no information available its tolerance. In this hydroponic experiment, variations in leaf anatomical morphology, chloroplast ultrastructure, stomatal characteristics, antioxidant enzyme activities were investigated under six levels polyethylene glycol 6000 (PEG)-induced treatments assess adaption physiological response C. seedlings. The results showed that PEG-induced reduced epidermis, spongy tissue, vein diameter, ratio, whereas ratio palisade tissue cell tense protuberant degree all increased enhancing PEG6000 concentrations. Significant differences width, aperture, density existed among (p < 0.01). aperture decreased significantly increase concentrations, greatest was observed 15% treatment. Compared control, higher stresses (20% 25% PEG concentrations) caused damage at cellular level lysis occurred. also promoted SOD, POD, CAT seedlings, insufficient deal membrane lipid peroxidative high Correlation analysis indicated cases there significant relationships between characteristics activities. Our suggested seedlings would not survive well when concentration over (equal soil water potential −0.30 MPa).