花椒品种抗冻性比较研究

Comparison Studies on the Freezing Resistance in Zanthoxylum bungeanum

秦安1号、油椒和大红袍是甘肃省花椒主产区的主要栽培品种。对其一年生休眠枝在不同低温(0^-40℃)处理不同时间(24~72h),通过测定相对电导率、超氧物岐化酶(SOD)活性和丙二醛(MDA)含量,对花椒品种休眠枝的抗冻性进行了比较研究。结果表明,各品种休眠枝的相对电导率和MDA含量从低到高均依次为:秦安1号<油椒<大红袍,品种间差异性均达到显著水平(P<0.05);SOD活性秦安1号略高于油椒,二者差异性虽未达到显著水平,但均显著高于大红袍(P<0.01);相同温度下,3品种休眠枝的相对电导率、MDA含量均随低温持续时间的延长而升高,大红袍休眠枝上升更加明显。SOD活性均随处理时间的延长而降低。引起各花椒品种休眠枝低温伤害的临界温度范围为-15^-20℃。从相对电导率、MDA含量和SOD活性的变化综合分析,供试的3个花椒品种中,秦安1号的抗冻性最强,油椒次之,大红袍抗冻性最弱。

Qingan No. 1, Youjiao and Dahongpao are main Zanthoxylum bungeanum cultivars in Gansu province. One-year-old dormant shoots of the above three cultivars were used to determine relative conductivity, MDA concentration and SOD activities under different low temperatures （0～-40℃ ） for different time （24-72 h）. The result showed that the relative conductivity and MDA varied in the same trend in the three cultivars, and their levels are arrayed as Qingan No. 1〈Youjiao〈Dahongpao, and the difference among them was significant （P〈0.05）. The SOD activity in Qingan No. 1 dormancy branch was higher than that in Youjiao branch, but the difference was not significant. However, the SOD activity in both Qingan No. 1 and Youjiao branch were significant higher than that in Dahongpao branch （P〈0.01）. When frozen under the same temperature, the relative conductivity and MDA concentration went up with freezing elongation and Dahongpao branch showed a significant increase trend. SOD activities were decreased with freezing elongation. The critical freezing temperature to Zanthoxylum bungeanum ranged from -15℃ to -20℃. From above the relative conductivity, MDA concentration and SOD activities, we may conclude that the freezing resistance varied with cultivars, their order from strong to weak as Qingan No. 1〉Youjiao〉Dahongpao.