保存8~33年的苹果试管苗增殖能力与端粒长度分析

为分析苹果试管种质端粒长度与繁殖能力、衰老的关系,探索端粒长度与苹果试管种质离体保存年限的关系,对保存多年的不同继代次数的3个苹果品种试管苗进行了表型、增殖能力以及端粒长度的研究。结果表明:保存了8~33年的‘富士’、保存8~27年的‘金冠’和保存8~25年的‘嘎拉’苹果茎尖试管苗继代增殖能力大部分没有变化,表型未发生明显变化;3个品种不同继代次数30 d苗龄试管苗叶片端粒长度均差异不显著;继代73代苗龄分别为10、30、50和90 d的试管苗叶片端粒长度变化因品种而异,‘富士’‘嘎拉’差异不显著,‘金冠’50 d苗龄的最长,90 d苗龄的最短;继代71代苗龄30 d的‘金冠’试管苗茎段端粒长度显著高于叶片,茎段和愈伤组织、叶片和愈伤组织之间差异不显著,‘嘎拉’表现为愈伤组织>叶片>茎段。苹果试管苗端粒长度变化与其增殖能力、表型及同一继代周期内衰老程度的变化相吻合。

Analysis of Proliferation Abilities and Telomere Lengths of Apple Plantlets in Vitro Preserved for Eight to Thirty-three Years

In order to examine the relationship between telomere lengths and their propagation ability or aging,and to explore the relationship between the telomer lengths and the preservation time limit in apple plantlets in vitro,the phenotypes,proliferation characteristics,and telomere lengths of apple plantlets preserved in vitro and consecutively subcultured for years were studied in three apple cultivars.The results showed that there were no changes in the proliferation abilities and no significant changes in phenotypes in most apple shoot plantlets in vitro from 8 to 33-year‘Fuji’preserved,8 to 27-year‘Golden Delicious’preserved,and 8 to 25-year‘Gala’preserved,respectively.No significant change in telomere lengths was found in leaves of the plantlets at 30-day plantlet age with different subculture times in three cultivars.The telomere lengths in the 73th subculture time plantlets could change during the given subculture periods,such as 10,30,50,and 90 days,which showed cultivar specificity.For example,there was no significant difference of telomere lengths in plantlet leaves of‘Fuji’and‘Gala’,while the telomere lengths in plantlet leaves of‘Golden Delicious’were the longest at 50-day and the shortest at 90-day.The telomere lengths in the 71th subculture time plantlet stems cultured for 30 days of‘Golden Delicious’,were significantly higher than that in leaves,and no significant difference was found either between those in stems and calli or in leaves and calli;while in‘Gala’,the telomere lengths in calli were the longest,followed by that in leaves and stems.The changes of the telomere lengths in apple plantlets in vitro coincided with their proliferation abilities,phenotypes,and aging during the same subculture time.