基于幼化效果的山杏组培繁殖技术研究

Tissue Culture Propagation Technique of Armeniaca sibirica Based on Rejuvenation Effect

以山杏为试验材料,选取不同部位、不同树龄、不同继代次数的组培苗,研究基于丛生芽诱导率和组培苗生根率、形态指标、生理指标3个层次的幼化效果。结果显示:(1)随着山杏外植体取材部位从树冠上部、中部、下部的依次下降,其丛生芽诱导率和组培苗生根率依次升高且部位间差异显著,其组培苗的株高、叶长、叶宽、根系数量和根系长度也随外植体取材部位下降而增加,但仅根系数量和根系长度在部位间差异显著,但其组培苗和母树叶片SOD活性、POD活性和MDA含量却逐渐降低,且组培苗叶片始终低于母树叶片。(2)随着取材母树的树龄从10a、4a、1a的不断降低,组培苗上述各项指标值均依次升高,1a树龄丛生芽诱导率及组培苗生根率、根系数量、根系长度分别为80%、96.6%、4.3条、2.40cm,极显著高于相应的10a和4a树龄的组培苗。(3)从初代培养到1次、2次继代培养,随着继代次数的增加,各类组培苗的丛生芽诱导率、株高、叶长和叶宽值不断增大,且以2次继代培养的增幅较大;同时相应组培苗叶片SOD活性、MDA含量和POD活性则呈下降趋势,但仍表现为2次继代的组培苗幼化效果较好。研究认为,各层次幼化效果指标在组培苗中表现出相同的变化规律。随着外植体在母树上取材部位的下移、取材母树年龄的降低以及组培苗继代次数的增加,山杏丛生芽诱导率和组培苗生根率、形态指标、生理指标表现出一致的变化趋势,其组培幼化效果愈来愈佳。

In order to explore the rejuvenation effect based on three levels which included the induction rate of multiple shoots and the rooting rate,morphological indexes and physiological indexes,we used Armeniaca sibirica as trial material and selected the tissue culture seedling of different positions,ages and subculture times.The results showed as follows：（1）the indexes of every rejuvenation effect showed the same variation rule in tissue culture seedling.When the sampling position of A.sibirica explants decreased which was from the crown of upper-middle-lower,the induction rate of multiple shoots and the rooting rate of tissue culture seedling were keeping rising in turn.The difference among positions was significant.The value of plant height,leaf length,leaf width,root number and root length also increased along with the decline of the explant sampling position.Only the difference of root number and root length were significant between positions.But the SOD activity,POD activity and MDA content of leaves decreased gradually,and those in leaves of tissue culture seedling were always lower than that in seed tree leaves.（2）Withthe decreasing of seed tree age which was from 10a-4a-1a,the above indexes values of tissue culture seedling all raised in turn.The rooting rate,root number root length of tissue culture seedling and the induction rate of multiple shoots which was from 1awere higher significantly than the corresponding indexes of 10 aand 4a.The values were 80%,96.6%,4.3and 2.40 cm,respectively.（3）From primary culture to first and second subculture,the induction rate of multiple shoots,plant height,leaf length and leaf width of various tissue culture seedlings increased constantly with the increasing of subculture times and the second subculture had larger increasing.The SOD activity,MDA content and POD activity of leaves appeared downward trend in tissue culture seedling,but still behaved that the tissue culture seedling of second subculture had the better rejuvenation effect.In summary,with the moving down of explant sampling positions,the decreasing of sampling age in seed tree and the increasing of subculture times in tissue culture seedling,the induction rate of multiple shoots and the rooting rate,morphological indexes,physiological indexes of tissue culture seedling showed the consistent trends,and the rejuvenation effect of tissue culture was better.