以黄瓜品种津优35号为试验材料,研究在低温弱光次生盐渍化[16 ℃/10 ℃、(140± 10) μmol/( m2 s)、50 mmol/L Ca( NO3) 2]复合逆境胁迫下分别喷施精胺、油菜素内酯、三十烷醇、褪黑素、腐胺对黄瓜幼苗生长、抗氧化系统和光合作用的影响.结果表明,低温弱光次生盐渍化复合逆境下黄瓜幼苗的超氧化物歧化酶(SOD)、过氧化氢酶(CAT)活性降低,而过氧化物酶(POD)活性升高,丙二醛(MDA)累积量增加,膜透性增强,幼苗的光合速率(Pn)、蒸腾速率(Tr)、气孔导度(Gs)及胞间CO2浓度(Ci)显著下降,幼苗的干质量、鲜质量分别显著减少,生长受到显著抑制.叶面喷施油菜素内酯、三十烷醇、褪黑素、腐胺可有效提高低温弱光次生盐渍化复合逆境下黄瓜幼苗的抗氧化酶活性,减轻其膜脂过氧化程度,增强其光合性能,显著增加幼苗干质量、鲜质量,综合比较以三十烷醇和腐胺的喷施效果最佳,其次是油菜素内酯和褪黑素处理.%An experiment was conducted to investigate the effects of spermine(Spm),Epi-brassinolide(EBR),tri-acontanol (TA),melatonin(MT) and putrescine (Put) on growth, antioxidant system and photosynthesis of cucumber seedlings under complex stress[16℃/10℃,140±10 μmol/( m2 s),50 mmol/L Ca(NO3)2]. Compared with the con-trol,the activity of superoxide dismutase and catalase decreased, the peroxidase activity, the malondialdehyde accumula-tion and cell membrane permeability significantly increased, the leaf net photosynthetic rate ( Pn), transpiration rate (Tr), stomatal conductance (Gs), in-tercellular CO2concentration (Ci), dry and fresh matter accumulation decreased in the adverse environment, re-spectively. However, applying EBR, TA, MT and Put could further improve the antioxidant enzyme activity,re-duce the membrane permeability of seedlings,make the leaves keep a higher photosynthetic rate,promote the seedlings growth. Comprehensive comparison,TA and Put treatment were most effective,followed by the EBR and MT treatment.
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