Study On The Effect Of Exogenous Hormones On Flower Bud Differentiation Of Physalis Pubescens

In order to provide theoretical reference for the regulation and management of the flowering stage and high quality and yield,GA and ABA of different concentrations were sprayed at the seedling stage under the condition of light incubator.The results are those as follows:1.Exogenous GA treatments of different concentrations could increase the content of GA and ABA in leaves.With GA75 mg/L treatment,GA and ABA contents of leaves reached the highest content,which were 9.60?g/g and 54.20?g/g,respectively.ABA treatment had little effect on GA content in leaves.At the early stage of flower bud differentiation,ABA content in leaves was significantly increased with treatment of exogenous ABA25 mg/L,while at the late stage of flower bud differentiation,ABA content in leaves was significantly increased with treatment of exogenous ABA50 mg/L.2.Both exogenous GA and ABA treatments could increase carbohydrate content i and reduce total nitrogen content in leaves,resulting in C/N ratio promoting significantly to accelerate lower bud differentiation.With the increase of GA application concentration,t the C/N ratio of leaves increased.When GA was applied at 100 mg/L,the C/N ratio of the leaves reached the maximum value of 3.58.The rank of C/N ratio in leaves treated by ABA at different concentrations was 50 mg/L>25 mg/L>75 mg/L>100 mg/L>CK.With 50 mg/LABA treatment,the C/N ratio reached the highest,which was 3.47.3.Exogenous GA and ABA treatments can significantly improve the contents of soluble sugar,soluble protein,sucrose,fructose,etc,clucose content,amylase activity in leaves,while reduce the glucose content and amylase activity.The activities of soluble proteinand contents of glucose,sugar,starch and amylase in leaves treated with 75 mg/L GA were significantly higher than other treaments.However,the contents of soluble sugar,sucrose and fructose in the leaves treated with spraying concentrations of 100mg/L,25 mg/L and 50 mg/L reached the highest values,respectively.The contents of soluble sugar,sucrose,fructose,glucose and soluble sugar in leaves treated with ABA50 mg/L were significantly higher thanother treatments.However,the maximum values of protein content,starch content and amylase activity were achieved by spraying 75mg/L,25 mg/L and 100 mg/L,respectively.4.Observation of paraffin sections of the terminal bud of Physalis pubescens L.showed that the bud differentiation stages could be divided into five stages: initial stage sepal stage,petal stage,stamen stage and pistil stage.ABA and GA treatments could promote the process of flower bud differentiation,but the effects were different.With ABA treatment,bud differentiation,sepal primordium differentiation and petal primordium differentiation initiatedat the axil of the second leaf,the third leaf anf the fourth leaf,respectively.Flower bud differentiation was completed at the axil of the fifth leaf,so the rate of differentiation was faster.In the case of exogenous GA treatment,floral bud differentiation was initiated in two leaves,sepal primordium differentiation was started in three leaves sepal primordium differentiation was completed in four leaves and petal primordium differentiation began in five leaves at a slower rate.5.With different application concentrations,rank of the initial flowering stage of the exogenous GA treatment was: CK>100 mg/L>25 mg/L>50 mg/L>75 mg/L,and the initial flowering stage of the 75 mg/L treatment was 6 days earlier than the control.However,the initial flowering axil of all treatments was the same,which was the seventh axil.The initial flowering stage treated by ABA was ranked as follows: CK>100 mg/L>25 mg/L>50 mg/L>75 mg/L.and the flowering stage of the 75 mg/L treatment was 11 days earlier than the control.Among the treatments of different flowering axils,initial flowering stages of ABA 75 mg/L and 50 mg/L treatments as well as 25 mg/L and 100 mg/L were the fifth and seventh axil respectively,while that of the control was seventh axil.Therefore,GA treatment did not change the initial flosering node,while ABA treatment with appropriate concentration reduced the initial flower node of the Physalis pubescens L..