新疆野苹果矮化性状形态学与生理指标评价

Dwarf evaluation on morphology and physiological indexes of Xinjiang wild apple

【目的】确定新疆野苹果GB-21是否具有矮化性,为苹果矮化资源的鉴定和筛选提供理论参考依据。【方法】以引种资源圃中3株疑似矮化的同一种下类型的新疆野苹果GB-21-1、GB-21-2和GB-21-3为研究材料,以乔木烟富3号(以下简称为“YF3”)为对照,选择新梢生长量、节间长、枝皮率、叶面积、栅海比、枝条电阻、叶片水势、叶绿素含量和酶活性等形态学及生理指标进行测定,应用综合指标对材料的矮化性进行评价。【结果】不同日期测定的GB-21-1、GB-21-2、GB-21-3的新梢生长量均大于YF3的;除4月28日外其余日期测定的GB-21-1、GB-21-2和GB-21-3的1年生枝条基部粗度均大于YF3的;GB-21-1、GB-21-2和GB-21-3的节间长分别为1.681 1、1.682 7、1.618 8 cm,均极显著小于YF3的(1.903 9 cm);GB-21-1、GB-21-2和GB-21-3的枝皮率分别为0.214 3、0.218 1、0.255 0,均极显著大于YF3的(0.177 3);不同日期测定的GB-21-1、GB-21-2、GB-21-3叶片的面积与厚度均小于YF3的;GB-21-1、GB-21-2、GB-21-3叶片的栅海比分别为1.21、1.44、1.37,均大于YF3的(0.99);GB-21-1、GB-21-2、GB-21-3的枝条电阻分别为5.80、5.57、5.20 MΩ,均极显著小于YF3的(7.98 MΩ);除4月28日外其余日期测定的GB-21-1、GB-21-2、GB-21-3的叶片水势均小于YF3的;除4月28日、5月23日外其余日期测定的GB-21-1、GB-21-2、GB-21-3的叶绿素相对含量均极显著高于YF3的;7月12日、8月6日、8月31日测定的GB-21-1、GB-21-2、GB-21-3的叶片过氧化物酶活性(POD)均极显著低于YF3的,而不同日期测定的其超氧化物歧化酶活性(SOD)均高于YF3的,7月12日、8月6日、8月31日和9月25日测定的其过氧化氢酶(CAT)活性均高于YF3的。【结论】GB-21-1、GB-21-2、GB-21-3的枝条节间短、枝皮率高,其叶片小而厚、栅栏组织较海绵组织发达,且其枝条电阻、叶片水势均较低,而其叶片CAT、SOD活性均较高,除叶片厚度、水势等个别指标外,其余指标的测定值与乔木YF3的差异均极显著。因此认为,GB-21-1、GB-21-2、GB-21-3极有可能均具矮化特征。

【Objective】The aim was to determine whether Xinjiang wild apple GB-21 had dwarfing property, and to provide certain theoretical reference and basis for the identification and screening of apple dwarfing resources.【Method】Three Xinjiang wild apples trees(GB-21-1, GB-21-2 and GB-21-3) of the same infra-species with suspected dwarfing in the introduction resource nursery were used as materials, and Arbor Yanfu 3(hereinafter referred to as YF3)was used as the control. The morphological and physiological indexes such as shoot growth, internode length, branchcortex ratio, leaf area, palisade spongy ratio, branch resistance, water potential, chlorophyll content and enzyme activity were determined, and the dwarfing property of the materials was evaluated by comprehensive indexes.【Result】The shoot growth of GB-21-1, GB-21-2 and GB-21-3 in different periods was greater than YF3;except April 28, the basal diameter of 1-year-old branches in GB-21-1, GB-21-2 and GB-21-3 were greater than YF3. The internode lengths of GB-21-1, GB-21-2 and GB-21-3 were 1.681 1, 1.682 7 and 1.618 8 cm, respectively, which were significantly less than YF3(1.903 9 cm);the branch-cortex ratio of GB-21-1, GB-21-2 and GB-21-3 were 0.214 3, 0.218 1 and 0.255 0, respectively,which were significantly higher than YF3(0.177 3);the leaf area and thickness of GB-21-1, GB-21-2 and GB-21-3were less than YF3 at all stages;the palisade spongy ratio of GB-21-1, GB-21-2 and GB-21-3 were 1.21, 1.44 and 1.37,respectively, which were higher than YF3(0.99);the branch resistances of GB-21-1, GB-21-2 and GB-21-3 were 5.80,5.57 and 5.20, respectively, which were significantly less than YF3(7.98);except for April 28, the water potential of GB-21-1, GB-21-2 and GB-21-3 leaves during the rest period was less than YF3;except for April 28 and May 23, the relative chlorophyll contents of GB-21-1, GB-21-2 and GB-21-3 were significantly higher than YF3;the peroxidase activities(POD) of GB-21-1, GB-21-2 and GB-21-3 leaves on July 12, August 6 and August 31 were significantly lower than those of YF3, while the superoxide dismutase activities(SOD) were higher than those of YF3 at all stages, its catalase activities(CAT) were higher than those of YF3 on July 12, August 6, August 31 and September 25.【Conclusion】The branches of GB-21-1, GB-21-2 and GB-21-3 had short internodes and high branch-cortex ratio, their leaves were small and thick,the palisade tissue was more developed than the spongy tissue, and the branch resistance and leaf water potential were low, while the activities of CAT and SOD in leaves were high. Except for some indexes such as leaf thickness and water potential, the indexes of GB-21-1, GB-21-2 and GB-21-3 could reach extremely significant differences with YF3. It was considered that GB-21-1, GB-21-2 and GB-21-3 were highly likely to have dwarfing characteristics.