摘要
以‘圆叶红花’口红花为试材,研究不同低温胁迫(昼/夜温度16℃/12℃、12℃/8℃、8℃/4℃、4℃/0℃)、胁迫时间及温度回升过程中叶片相关生理指标的变化规律,旨在探讨口红花叶片在低温逆境下的生理响应。结果表明:昼/夜温度在12℃/8℃以上对口红花叶片影响不大,4℃/0℃以下低温会造成口红花叶片死亡,其耐寒性鉴定可选在昼/夜低温8℃/4℃下进行;在昼/夜低温8℃/4℃胁迫下,各测定指标与相对电导率(REC)和叶片含水量均呈显著或极显著相关性,叶绿素含量与超氧化物歧化酶(SOD)活性呈极显著正相关,丙二醛(MDA)含量与过氧化氢酶(CAT)活性呈极显著负相关;REC、MDA含量、叶片含水量、叶绿素含量、SOD和CAT活性是影响和评价口红花耐寒性的重要指标。
Aeschynanthus radicans is one of the most popular hanging plants. Now, for its high visual value of leaves and flowers, A. radicans has been often used as indoor ornamental and also plays an important role in landscaping. In Zhejiang Province, A. radicans has been widely cultivated; however, it often suffers from cold in winter. In the recent years, some researches on plant naturalization and tissue culture of A. radicans have been reported, whereas little information is available regarding cold resistance of A. radicans thus far. Therefore, it is necessary to characterize the physiological effects o{ low temperature on A. radicans. These studies might make technological assistance for plant growth and development under low temperature, and provide a basis for new variety selection with improvements on cold resistance. The purpose of the present study is to investigate the cold tolerance characteristics of A. radicans leaves, to show the physiological responses of A. radicans to low temperature stress, and to choose some physiological indicators for evaluating the cold tolerance of A. radicans. In this study, some physiological traits, that is, relative electric conductivity （REC）, water content, chlorophyll content, malondialdehyde （MDA） content, activities of superoxide dismutase （SOD） and catalase （CAT）, were studied for biennial cutting plants of A. radicans variety ＇ Round leaf and red flower＇ under different clay/night low temperature stress （16℃/12 ℃, 12 ℃/8℃, 8℃/4 ℃, 4 ℃/0℃）, different stress time and recovery growth time. The results indicated that： 1） The REC values of A. radicans leaves increased gradually with the decrease of temperature and the elongation of treatment time. Also, the REC values showed significant difference among treatments under four kinds of temperatures. The tendency of chlorophyll content and water content declined with the elongation of treatment time under low temperatures and then ascended gradually, and received a peak at The content of MDA under cold stress descended at first 10 h. The SOD activity increased slowly under low temperature, rose to the maximum at 4 d, and then decreased gradually, with a minimum at 10 d. Among the treatments with different low temperatures, the SOD activity showed a decline tendency with lower temperatures. 2） The results showed that all determined traits had no obvious distinctness when day/night temperatures exceeded 12℃/8℃, and leaves death would take place below 4 ℃/0 ℃. Therefore, 8 ℃/4 ℃ group was considered to be a suitable day/night temperature for cold tolerance evaluation. 3） The REC and water content were significantly correlated with the other investigated traits. Besides, a significant positive correlation was detected between chlorophyll content and SOD activity, whereas a significant negative correlation between MDA content and CAT activity was discovered. In a word, the proper day/night temperature for cold tolerance evaluation of A. radicans was 8 ℃/4 ℃. REC, MDA content, water content, chlorophyll content, SOD and CAT activity could be used as physiological indicators in cold tolerance evaluation of A. radicans. The findings of this study would be useful for selecting new varieties with improved cold resistance.
出处
《浙江大学学报（农业与生命科学版）》
CAS
CSCD
北大核心
2012年第5期559-565,共7页
Journal of Zhejiang University:Agriculture and Life Sciences
基金
浙江省重大科技专项项目(2009C12095)
浙江省科技资助项目(2010C32052)
关键词
口红花
低温胁迫
生理响应
Aeschynanthus radicans
low temperature stress
physiological index
