低温胁迫对我国北方地区引种的无花果抗寒性的影响

Effects of low temperature stress on cold resistance of introduced fig (Ficus carica) in North China

为给无花果抗寒能力的评价与抗寒品种的选育提供参考依据,以我国北方地区引种的14个无花果品种为研究对象,采用人工低温(0^-20℃)处理对其1年生枝条进行了胁迫试验,并对其相对电导率、可溶性蛋白含量、可溶性糖含量、脯氨酸含量、SOD活性、POD活性和MDA含量进行了测定,还根据相对电导率和对应的低温温度,依据logistic方程,建立了回归模型,对14个无花果品种的抗寒性进行了综合评价。结果表明:依据半致死温度来评价,布兰瑞克、ALMA等品种的抗寒性均较强,-5^-10℃的低温会严重影响参试的大部分品种的生存和生长发育;其SOD和可溶性糖在-10℃时的测定值是反映无花果抵抗和适应低温能力的一个临界值,而可溶性蛋白和POD的临界值是在处理温度为-5℃时的测定值。部分品种的综合抗寒能力的评价结果与其半致死温度的测定结果存在差异,但新早黄、ALMA、金傲芬和紫蕾等品种均具备较好的抗寒潜力。

In order to provide some references for evaluation of cold resistance and breeding of cold-resistant cultivars of fig, using fourteen cultivars planted in Northern China as study objects, one-year branches were tested under artificial low temperature conditions （from 0 ℃ to - 20 ℃ ）, and their relative conductivity, soluble protein content, soluble sugar content, proline content, SOD activity, POD activity and MDA content were measured. Moreover, according to the relative conductivity and corresponding temperatures, a regression model was established based on the logistic equation, and cold resistances of fourteen fig cultivars were comprehensively evaluated. The results showed that according to the semi-lethal temperatures, the cultivars such as Branswick and ALMA had strong cold resistance; low temperature （from - 5 to - 10℃ ） could seriously affect survival, growth and development of most tested cultivars; the measured values of SOD activity and soluble sugar content at - 10 ℃ were the critical values reflecting the ability of cold resistance and adaptation of fig cultivars, while the critical values of soluble protein content and POD activity were the values measured at - 5 ℃. There were some differences between evaluation results of comprehensive cold resistance ability and their measured semi-lethal temperatures of some cultivars, but some cultivars such as Xinjiangzaohuang, ALMA, Orphan and Violette Solise had good cold resistance potential.