College of Jiyang, Zhejiang AF University, Zhuji 311800, China.
Int J Mol Sci. 2023 Jul 6;24(13):11180. doi: 10.3390/ijms241311180.
In order to explore the effects of high temperature stress on the physiological characteristics of , the were subjected to 25 °C, 35 °C, 38 °C, and 40 °C for 7 days. Meanwhile, the physiological indicators of oxidative stress (hydrogen peroxide, HO; malondialdehyde, MDA; relative electrical conductivity, REC), antioxidant enzyme activity (superoxide dismutase, SOD; ascorbate peroxidase, APX; catalase, CAT; peroxidase, POD), photosynthetic pigment content (chlorophyll a, Chla; chlorophyll b, Chlb), photosynthetic characteristics (net photosynthetic rate, Pn; intercellular CO concentration, Ci; stomatal conductance, Gs; transpiration rate, Tr), and osmoregulatory substances content (soluble protein, SP; soluble sugar, SS) were determined. The results showed that, with the increase in temperature and stress time, the HO content, MDA content, REC value, CAT activity, and APX activity increased, while Chla content, Chlb content, SS content, and SP content decreased. With the extension of stress time, the SOD activity, POD activity, and Tr value of each high temperature stress group first increased and then decreased; Ci first decreased, then increased, and then decreased; meanwhile, Pn and Gs showed an overall downward trend. PLS-DA (partial least squares discriminant analysis) was used to analyze the changes in physiological and biochemical indexes of peony leaves under 40 °C stress for different days. SOD was found to be the biggest factor affecting the changes in physiological and biochemical indexes of peony leaves treated with different days of stress.
为了探讨高温胁迫对 生理特性的影响，将 置于 25°C、35°C、38°C 和 40°C 下进行 7 天处理。同时，测定了氧化应激生理指标（过氧化氢，HO；丙二醛，MDA；相对电导率，REC）、抗氧化酶活性（超氧化物歧化酶，SOD；抗坏血酸过氧化物酶，APX；过氧化氢酶，CAT；过氧化物酶，POD）、光合色素含量（叶绿素 a，Chla；叶绿素 b，Chlb）、光合特性（净光合速率，Pn；胞间 CO 浓度，Ci；气孔导度，Gs；蒸腾速率，Tr）和渗透调节物质含量（可溶性蛋白，SP；可溶性糖，SS）。结果表明，随着温度和胁迫时间的增加，HO 含量、MDA 含量、REC 值、CAT 活性和 APX 活性增加，而 Chla 含量、Chlb 含量、SS 含量和 SP 含量降低。随着胁迫时间的延长，各高温胁迫组的 SOD 活性、POD 活性和 Tr 值先升高后降低；Ci 先降低，后升高，再降低；同时，Pn 和 Gs 呈整体下降趋势。采用偏最小二乘判别分析（PLS-DA）对 40°C 不同胁迫天数下牡丹叶片生理生化指标的变化进行分析，发现 SOD 是影响胁迫不同天数下牡丹叶片生理生化指标变化的最大因素。
