Physiological Effects Of 6-BA,SA And ABA On Miniature Rose Under High Temperature Stress

Roses like cool temperatures,while in summer in Guangdong,due to high temperature and high humidity,miniature rose grow poorly and their value is low.The miniature rose varieties 'Maize' and 'Gold Coast' was used as materials in experiment,spraying different concentrations of salicylic acid,abscisic acid and cytokinin,and then placed in a light incubator for high temperature stress.Measured indicators include soluble protein,chlorophyll,malondialdehyde,and free proline content in the leaves,superoxide dismutase,peroxidase,and ascorbate peroxidase activity,and leaf relative electrical conductivity,the results showed that:1.When the miniature rose sprayed with salicylic acid,the content of proline and protein in leaves and the activities of SOD,POD and APX were significantly higher than those of the control.The MDA content and relative conductivity were significantly lower than the control.The results showed that spraying salicylic acid with suitable concentration on foliar surface could improve the stress resistance of mini rose under high temperature stress.In 5 spraying concentrations,the soluble protein,free proline content and SOD activity were significantly higher than those of other treatments with 2.0 mmol/L spraying,and POD and APX activity at 1.5 mmol/L were significantly higher than other treatments.2.With the prolongation of high-temperature stress,the activities of SOD,POD,and APX,and soluble protein and free proline content in the leaves of miniature rose that were sprayed with cytokinin were significantly higher than those of the control,relative electrical conductivity and MDA content were significantly lower than the control.In four spraying concentrations,The activities of SOD,POD and APX and the soluble protein and free proline content of the 'corn' varieties sprayed with 10?mol/L and the 'Gold Coast' varieties sprayed with 20?mol/L were significantly higher than other treatments,and the relative conductivity and MDA content was significantly lower than other treatments.3.In the miniature rose sprayed with abscisic acid,the activities of SOD,POD and APX,and free proline and protein content in the leaf were significantly higher than those of the control with the prolongation of high temperature stress.The MDA content and relative conductivity were significantly lower than the control.In 5 spraying concentrations,the soluble protein and free proline content and the SOD,POD and APX activities of the 'maize' varieties sprayed with 20 mg/L and the 'Gold Coast' varieties sprayed with 10 mg/L were significantly higher than other treatments,and the relative conductivity and MDA content was significantly lower than other treatments.4.After spraying three kinds of hormones,the leaf chlorophyll content of the miniature rose was higher than that of the control.Especially when spraying the best concentration,the content of chlorophyll was significantly higher than that of the other treatments and the control;indicating the suitable concentration of salicylic acid,Cytokinin and abscisic acid can effectively alleviate the degradation of chlorophyll under the high temperature stress in the miniature rose,and contribute to its resistance to adversity.5.Taken together,spraying salicylic acid,cytokinin,and abscisic acid all contribute to alleviating the damage caused by high temperature stress to the miniature rose.Among them,salicylic acid has a better alleviation effect.In the treatment with 5 concentrations of salicylic acid,the treatment with 2.0 mmol/L of spray was better.