Study On Cold Resistance Of Two Rosa Rugosa Cultivars

Rosa rugosa’kushui’and Rosa rugosa’lengxiang’ are good ornamental flowers and garden green plants.They have brightly colored flowers and very lush, very enchanting.Their prospects are extremely broad in garden applications. In cold regions of Heilongjiang, the temperature of the restrictions led to fewer species of landscaping and production. The study on cold resistence of the two flowering shrubs, is to provide a theoretical basis for introducting flowering shrubs and landscape applications in the Heilongjiang region.This paper took the detached dormant branches of the two species as the experimental materials. After artificial low-temperature stress,the physiological and biochemical indexes were determined and analyzed to study cold relationship with plants.The cold resistance characteristics of the two roses were systematically investigated by the integrating use of logistic equation, variance analysis, multiplecomparative analysis. Simultaneously we made the wintering adaptive evaluation, the growth rhythm, ornamental evaluation for two roses.And preliminarily explorate CBF cold resistance gene in rose. The major results were summarized as follows:1、In artificial cold acclimation experiments, the relative conductivity, MDA content, soluble sugar content, soluble protein content of the two roses branches increased with the duration of stress time; free proline content and POD activity are in up-down-up-down trend; SOD activity was increased and then decreased. Use Logistic Regression equation to coculate the inflection point temperature and determine the semilethal temperature (LT50) of Rosa rugosa’kushui’ranging is-40.2℃; the semilethal temperature range (LT50) of Rosa rugosa’Lengxiang’was-38.9℃, matched the growth recovery experimental results. The sustained low temperature stress can cause plant damage intensifying,then cold resistance weaked. Shows that the conductivity, soluble sugar and other physiological and biochemical indices with plant cold tolerance have a certain relevance.2、Under the same stress time, the relative conductivity, MDA content of the rwo roses are decreased with temperature rise; soluble protein content was increased in the first stage and then decreased; the free proline content are in up-down-up-down trend; soluble sugar content Protective Enzymes were positively correlated with plant coldness. In the growth recovery experiments, The budding rates of frozen branches decreases as the temperature gets lower. And the budding rates of Rosa rugosa ’Lengxiang is higher than Rosa rugosa’kushui’.It’s consistent with changes of other physiological indicators.3、By overwintering adaptability evaluation, the phenophase and the growth rhythm ovservation, the two rose species to be introduced to Harbin region can be normal growing development, but slightly in different phenophases, and its annual’ growth was slightly lower than the origin. Shows that Rosa rugosa ’Kushui’and Rosa rugosa ’Lengxiang’are suitable to grow in Harbin, and fancypoints are basically the same as the origin, the introduction of Rosa rugosa ’kushui’and Rosa rugosa ’lengxiang’ is feasible for lanscape applications.4%The rose CBF transcription factor genes are initially explorated by molecular techniques. The experiment gets clear bands which included rose CBF gene fragment by PCR. After discussion, analysis,we speculated rose cold resistance contect with the CBF transcription factor inside the rose.