不同方法测定桃树抗寒性关系研究

Study on the relationship of cold resistance of peach tree by different methods

以生产中抗寒性表现较强、中等、较弱的3个桃品种为试材,应用电解质渗透法(EL)和电阻抗图谱法(EIS)研究了不同时期枝条抗寒性和未经冷冻处理枝条EIS参数的变化,并对未经冷冻处理枝条EIS参数、冷冻处理枝条EIS参数测定的半致死温度与EL测定的半致死温度的关系进行了统计分析。结果表明:未经冷冻处理3个桃品种的胞外电阻率(r_e)和胞内电阻率(r_i)均随着外界温度的降低而升高,随着外界温度的升高而降低;弛豫时间(τ)与r_(e)、r_(i)变化趋势相反;通过对4个电阻抗参数与EL测定的半致死温度统计分析得出,EIS(r_(i))是最佳参数,其相关系数为-0.828,通径系数为-7.385,线性回归方程为y=-4.063 9x+4.333 8,R^(2)=0.686。EL和EIS参数法测定3个桃品种的抗寒性与生产上抗寒性强弱表现一致;通过对2种方法统计分析得出,EL与EIS 4个参数法测定抗寒性均呈极显著正相关,其中弛豫时间法相关系数、通径系数和决定系数均最高,因此,弛豫时间是预测冷冻处理桃树枝条抗寒性的适宜参数。

Three peach varieties with strong,medium and weak cold resistance during production were selected as test materials,the changes of cold resistance and EIS parameters of branches without freezing treatment at different periods were studied by electrolytic osmosis(EL)and electrical impedance mapping(EIS),the relationship between EIS parameters of branches without freezing treatment and the semi-lethal temperature estimated by EL method was statistically analyzed,the relationship between the semi-lethal temperature estimated by EIS and the semi-lethal temperature estimated by EL method was statistically analyzed.The results showed that the extracellular resistivity(re)and intracellular resistivity(ri)of the three varieties without freezing increased with the decrease of external temperature,and decreased with the increase of external temperature,relaxation time(τ)with r_(e) and r_(i) in opposite change tendency;According to the statistical analysis of the four electrical impedance parameters and the semi-lethal temperature estimated by EL method,EIS(r_(i))is the best parameter,the correlation coefficient is-0.828,the path coefficient is-7.385,the linear regression equation is y=-4.0639x+4.3338,R^(2)=0.686.The cold resistance of three peach varieties measured by EL method and EIS parameter method was consistent with the cold resistance in production.The statistical analysis of the two methods shows that EL method and EIS four parameter methods have extremely significant positive correlation with cold resistance,and the correlation coefficient,path coefficient and determination coefficient of the method of relaxation time are the highest.Therefore,relaxation time is an appropriate parameter for predicting cold resistance of frozen peach branches.