【摘要】 以对羟基苯甲酸和苯丙烯酸为代表性酚酸类物质 ,研究其对黄瓜幼苗生长和保护酶活性的影响。结果表明 ,该 2种酚酸物质对黄瓜幼苗的生长有抑制作用 ,鲜重、株高、茎粗、叶面积均有减小 ,随处理浓度的增加抑制作用增强 ,苯丙烯酸比对羟基苯甲酸具有更强的抑制作用 ;与对照 (CK)相比 ,2种酚酸物质对过氧化物酶 (POD)活性的影响呈现出先升高、然后下降 ,最后低浓度处理有回升趋势而高浓度无回升趋势 ;对过氧化氢酶 (CAT)活性的影响则呈现出低浓度处理其活性先升高、然后下降、最后回升的变化趋势 ,高浓度处理首先表现为活性降低、然后略有升高、最后下降而无回升趋势 ;对超氧化物歧化酶 (SOD)活性的影响表现出首先高于CK ,然后逐渐下降低于CK ,最后低浓度处理逐渐回升趋于CK ,而高浓度处理无回升趋势。高浓度酚酸类物质使丙二醛 (MDA)含量增加更多还原

【Abstract】 Shandong Mici cucumber was taken as experimental plant variety. The applied phenolic acids were P hydroxy benzoic acid and cinnamic acid which were designed to four concentration (0 μmol/L, 50 μmol/L, 100 μmol/L, 150 μmol/L)treatments to study the effects of phenoic acids on the growth and the activities of protective enzymes of cucumber seedlings. The results showed that the two types of phenolic acids both inhibited the plant growth. The inhibitory effects were enhanced with increasing concentration of phenolic acids and prolonging time of treatment. Compared with the control, the growth of the cucumber under the treatments of A150(P hydroxy benzoic acid, 150 μmol/L),B50(cinnamic acid, 50 μmol/L),B100(cinnamic acid, 100 μmol/L), B150(cinnamic acid, 150 μmol/L) showed significant difference in the plant height and leaf area, and the inhibitory effect of cinnamic acid was more stronger than that of P hydroxy benzoic acid. For protective enzymes system [peroxidase (POD),catalase (CAT)], the results indicated that the POD activity increased firstly, then decreased , increased again finally under lower concentrations of phenolic acids but decreased at last under highter concentrations, and that the CAT activity increased firstly, then decreased, increased again finally under lower concentrations of phenolic acids, however, the activities decreased firstly, then increased a little, decreased continuously at last under higher concentrations. In addition, the treatments of phenolic acids led to a decrease of superoxide dismutase (SOD) activity and an increase of malonic aldehyde (MDA) content in the seedlings compared with the check. It proved that lot of activited oxygen were produced and protective enzymes were destroyed under highter concentrations of phenolic acids.更多还原