摘要
以GA_4处理的果梅休眠芽和转PmRGL2基因杨树叶片为材料,通过测定H_2O_2含量、抗氧化酶类活性及其编码基因和信号转导相关基因表达的变化,分析了H_2O_2在外源GA_4解除果梅休眠中的信号作用。结果表明:GA_4处理的果梅花芽的萌芽率显著高于对照,且H_2O_2含量在休眠解除时达到峰值,信号转导相关基因表达发生规律性变化;‘桃形梅’和‘丰后’的需冷量分别为574 CH(低温小时数Chilling hours)和1 108 CH,休眠解除前后,两品种叶芽中的H_2O_2含量没有显著差异,但需冷量低的‘桃形梅’具有更高的抗氧化酶类活性;转Pm RGL2杨树中NADPHoxi下调表达,有利于使H_2O_2含量维持在较低水平,并对赤霉素合成及信号转导相关基因的表达产生影响,而抗氧化酶类活性及其编码基因的表达量上升。推测GA_4通过调控抗氧化酶类活性而影响H_2O_2含量的变化,并引起上下游多种信号相关基因表达水平的变化,最终对休眠解除起作用。
In order to analyze the signal effect of H2O2 on seasonal dormancy release of Japanese apricot induced by exogenous GA4,the buds of Japanese apricot and transgenic poplar with Pm RGL2 gene were taken as the plant materials to investigate the content of H2O2,activities of antioxidant enzymes and gene transcriptional expression related to antioxidant enzymes and signal transduction. The results showed that the sprout rate of flower buds of Japanese apricot treated by GA4 was significant higher than that of the control and the content of H2O2 accompanied with the expression of signal transduction related genes and reached to a peak at the time of dormancy release. The chilling requirement of‘Taoxingmei’and ‘Bungo’Japanese apricots are 574 CH（Chilling hours）and 1 108 CH,respectively. The content of H2O2 in leaf buds did not have significant difference in both cultivars before and after dormancy release,while the activities of antioxidant enzymes were higher in the former one. The down-regulation expression of NADPHoxi and up-regulation of expression of the antioxidant enzymes related genes contributed to maintain the content of H2O2 in transgenic poplar with a low level,which could affect the genes expression associated with gibberellin synthesis and signal transduction. Above all,we suggested that GA4 may regulate the genes expression encoding antioxidant enzymes to affect the content of H2O2 which acted as a signal molecular to lead to signal gene expression changes related to seasonal dormancy release in Japanese apricot.
出处
《园艺学报》
CAS
CSCD
北大核心
2017年第2期255-267,共13页
Acta Horticulturae Sinica
基金
江苏省自然科学基金项目(BK20151426)
关键词
果梅
休眠
GA4
花芽
叶芽
H2O2
Japanese apricot
dormancy
GA4
floral bud
vegetative bud
H2O2
