【摘要】 探析不同温度条件下娃娃菜幼苗的生长、生理及光合特性，以确定其最适生长温度范围。以‘耐寒金皇后’娃娃菜为试材，采用完全随机区组试验设计，设置0、5、10、15、20、25（对照）、30、35℃共8个温度处理，测定株高、根颈粗、叶绿素含量、超氧化物歧化酶（SOD）活性、过氧化物酶（POD）活性、丙二醛（MDA）含量、净光合速率（Pn）、气孔导度（Gs）、蒸腾速率（Tr）、胞间CO₂浓度（Ci）等指标。结果表明，娃娃菜幼苗在0℃时植株开始死亡；5～15℃低温和30～35℃高温时娃娃菜株高、根颈粗增长缓慢；20℃时株高、根颈粗最大，长势良好，植株体内叶绿素含量、SOD活性、POD活性呈现出先增后降的趋势，MDA含量呈现先降后增的趋势。随着时间变化，娃娃菜的Tr、Gs、Pn和Ci呈上升趋势；在20℃时Pn达到最大，在35℃高温下娃娃菜幼苗Gs、Tr、Ci最大。温度低于20℃或高于25℃都会影响娃娃菜幼苗的生长，造成叶片酶活性下降，光合能力降低。综上，娃娃菜幼苗生长最适的温度范围为20～25℃，此范围内植株形态建成、生理代谢和光合性能表现最优。更多还原

【Abstract】 The growth, physiological and photosynthetic characteristics of Brassica pekinensis seedlings under different temperature conditions were analyzed to determine the optimal temperature range for their growth.Taking B. pekinensis‘Cold-resistant Golden Empress’ as test material, a completely randomized block design was used to set up eight temperature treatments of 0, 5, 10, 15, 20, 25（control）, 30 and 35℃. The plant height,root diameter, chlorophyll content, superoxide dismutase（SOD） activity, peroxidase（POD） activity,malondialdehyde（MDA） content, net photosynthetic rate（Pn）, stomatal conductance（Gs）, transpiration rate（Tr）, intercellular CO₂concentration（Ci） were measured. The results showed that the seedlings began to die at0℃. The plant height and root collar diameter increased slowly at 5-15℃ and 30-35℃. At 20℃, the plant height and root collar diameter were the largest, and the growth was good. The chlorophyll content, SOD activity and POD activity in the plant showed a trend of increasing first and then decreasing, and the MDA activity showed a trend of decreasing first and then increasing. With the change of time, Tr, Gs, Pn and Ci of B.pekinensis showed an upward trend. The Pn reached the maximum at 20℃, and the Gs, Tr and Ci of B.pekinensis seedlings were the largest at 35℃. Temperature lower than 20℃ or higher than 25℃ would affect the growth of B. pekinensis seedlings, resulting in a decrease in leaf enzyme activity and photosynthetic capacity.The optimum temperature range for the growth of B. pekinensis seedlings was 20-25℃, and the plant morphogenesis, physiological metabolism and photosynthetic performance were the best in this range.更多还原