| Dianthus caryophyllus L., also named as carnation, has high ornamental value and becomes one of the Fourth cut flowers, with great sales in the flower markets. It originated from the Mediterranean Region, which liked the cool and dry environment with poor heat resistance, so high temperature will affect the quality of cut flowers. One of the most important breeding goals is to breed the cultivation of heat resistant. Using Dianthus caryophyllus’Xiangxiang’as material, PmHSP25.3gene from Prunus mume was transferred to carnation mediated by Agrobacterium-mediated method, followed by resistance screening and PCR detection, and the transformed plants were achieved. At the same time, the physiological and biochemical changes about transgenic plants and non-transformed plants were measuredunder high temperature stress. The main findings are as follows:1Genetic TransformationLeaf explants were pre-cultured on MS+1.0mg/L BA+0.3mg/L NAA for2days, followed infection by Agrobacterium for8-12min, so begun the co-cultivation on medium containing100μmol/L acetosyringone (AS) for3days. After that, some resistant shoots appeared by screened on the mediun with60mg/L Kan and400mg/L Cef. tWhen the shoots grown up to about1cm, they were transferred to rooting medium with25mg/L Kan and400mg/L Cef. It is quite different in rate of shoot regeneration when the leaf was infected by different Agrobacterium strains, that the rate of leaf regeneration by EHA105strain infection was higher, reached about3.33%, while the one of GV3101is about0.41%. Two positive plantlets were detected in the target gene bands after DNA extraction and PCR testing.2Study on high temperature stress toleranceThe stress treatment of transgenic and control plantlets at different temperature was conducted, and it comes out that the lethal temperature of transformed carnations was49℃, while the control were45℃. The leaf was collected after treated at38℃for0,2,4,6and8days respectively, and stored in fridge for the detection of physiological and biochemical index. The results showed that the content of soluble protein and soluble sugar, and SOD activity of transgenic plantlets was higher than the control, while the total leaf chlorophyll and MDA content is lower than the control. |
