低温胁迫下袖珍椰子幼苗的某些生理学变化

Some Physiological Changes in Chamaedorea elegans Seedling under Low Temperature Stress

在2℃低温胁迫下,袖珍椰子(Chamaedorea elegans H.Wendl.)幼苗叶片的MDA含量逐渐增加,膜脂过氧化作用逐渐增强。电解质渗出率在3天后增至92.35%,细胞膜受到不可逆伤害。细胞保护酶SOD、POD和CAT酶活性呈现初期增高,随后下降的趋势,其中CAT酶活性降幅最大。叶片净光合速率随低温胁迫时间延长也呈现下降,5天后,净光合速率为-1.89μmolCO2(/cm2·s);蒸腾速率在低温处理4天内变化不大,5天时表现为显著下降。

Under 2 ℃ low temperature stress , malondialdehyde （MDA） content in leaves of Chamaedorea elegans H. Wendl. seedling gradually increased, reflecting that membrane lipid per oxidation aggravated. Electrolyte leakage increased to 92.35% after 3 days, cell membrane was damaged irreversible. Cell defense enzymes SOD, POD and CAT activity raised at early stage, and then lowered, especially enzymes CAT falls greatly. Net photosynthetic rate in leaves decreased to -1.89 μmol CO2/（cm^2· s） after 5 days; Transpiration rate in leaves changed little in 4 days, but sharp declined after 5 days.