一串红品种‘神州红’和‘帝王’对高温胁迫的响应

Responses of Salvia splendens cultivars 'Shenzhouhong' and 'Emperor' to thermo-stress

以自育的一串红新品种‘神州红’与进口品种‘帝王’为材料,在田间模拟自然高温及人工气候箱高温胁迫(40℃)条件下,研究高温胁迫对一串红生育期和田间生长指标以及一串红叶片叶绿素含量(SPAD值)、Fv/Fm(光系统Ⅱ最大光化学效率)、过氧化氢酶(CAT)活性、过氧化物酶(POD)活性、超氧化物歧化酶(SOD)活性、丙二醛(MDA)和脯氨酸含量的影响,并比较这2个品种的耐热性差异.结果表明:在田间模拟自然高温条件下,神州红比帝王的耐热性强,具体表现在‘神州红’花期较长,冠幅和花序长度均比帝王受高温影响的程度小;在人工气候箱高温胁迫条件下,2个一串红品种的叶绿素含量均降低,但2个品种未显示出耐热性差异;高温胁迫明显降低2个品种的Fv/Fm值和SOD酶活性,显著增加CAT和POD活性以及MDA和脯氨酸含量,且2个品种间的以上性状受高温影响的程度有明显差异;与‘帝王’相比,‘神州红’的光保护机制和活性氧清除系统较强.

In order to study the thermo-tolerance of two Salvia splendens Ker-Gawl cultivars, i.e. Shenzhouhong, a nationally-bred variety, and Emperor, an imported variety, some morphological and physiological traits were measured under high temperature stress, including relative content of chlorophyll （SPAD value）, Fv/Fm （maximum quantum yield of photosystem Ⅱ photochemistry）, CAT （catalase）, POD （peroxidase） and SOD （superoxide dismutase） activities, MDA （malondialdehyde） and proline contents. High temperature stresses were conducted in the field with natural high temperature and in the intelligent climate incubator at 40℃. The results showed that cultlvar ＇ Shenzhouhong＇ had longer florescence, and its rown diameter, inflorescence duration length were less affected by thermo- stress than cultivar ＇Emperor＇ under naturally high temperature. In the intelligent climate incubator at 40 ℃there was no significant difference in SPAD values between two cultivars. While thermo-stress resulted in significant reduction of Fv/Fm and SOD activity, and significant increase of CAT and POD activities, MDA and proline contents for two cultivars. Moreover, the changed extent of these physicochemical traits of the two cultivars differed greatly under high temperature stress. The results above suggest that cultivar ＇Shenzhouhong＇ shows much greater ability than cultivar ＇Emperor＇ in developing light protection and active oxygen scavenging system in response to thermo-stress.