论文部分内容阅读
采用超高效液相色谱—串联质谱(UPLC–MS/MS)的方法测定了25℃和4℃处理下‘凤丹’牡丹(Peaonia ostti‘Fengdan’)种子播种后8个时期的激素含量变化,并利用qRT-PCR分析GA_3和ABA信号转导4个关键基因的表达模式。结果表明:25℃处理下种子可以正常萌发,而4℃处理下种子在播种后100 d内未萌发。两种温度处理下种子中GA_3含量均呈现先升高后降低的趋势,但25℃处理播种后17 d(下胚轴萌发期)显著高于4℃处理;在25℃处理种子中ABA含量逐渐降低,而4℃处理下短时间降低后迅速升高,且在播种后7~17 d显著高于25℃处理。推测25℃处理下较高含量的GA_3可以促进种子萌发;而4℃处理下较高含量的ABA抑制种子萌发。qRT-PCR分析表明,PoGID1a和PoGAI的整体表达模式与GA_3含量变化趋势类似,呈现先升高后降低的趋势,但播种前期25℃处理下PoGID1a表达量一直显著高于4℃处理,而PoGAI却显著低于4℃处理(21 d除外);PoGAMYB4在25℃处理下呈升高趋势,在4℃处理下先升高后降低,但播种3 d后25℃处理显著高于4℃处理;PobZIP表达趋势与ABA含量变化相似,4℃处理显著高于25℃处理。故推测牡丹种子萌发受GA和ABA调控,GA通过调控信号转导关键基因PoGAMYB4、PoGID1a和PoGAI促进种子萌发,其中PoGAMYB4和PoGID1a可能受GA正调控,而PoGAI受GA负调控;ABA可能通过正调控PobZIP抑制种子萌发。
The changes of hormone content in ’Peaonia ostti’Fengdan’ seed at eight stages after sowing at 25 ℃ and 4 ℃ were determined by UPLC-MS / MS. QRT-PCR was used to analyze the expression patterns of four key genes of GA 3 and ABA signal transduction. The results showed that seeds germinated normally at 25 ℃, while the seeds did not germinate within 100 d after sowing at 4 ℃. The contents of GA 3 in the seeds increased firstly and then decreased with the increase of temperature, but the content of ABA in seeds treated with 25 ℃ was significantly higher than that at 4 ℃ 17 days after sowing (hypocotyl germination) Decreased rapidly at 4 ℃, but increased rapidly at 4 ℃ and decreased significantly at 25 ℃ after 7 ~ 17 days after sowing. It was speculated that the higher content of GA 3 at 25 ℃ could promote seed germination, while the higher content of ABA at 4 ℃ could inhibit seed germination. qRT-PCR analysis showed that the overall expression pattern of PoGID1a and PoGAI was similar to that of GA3, and then increased at first and then decreased. However, PoGID1a expression at 25 ℃ was significantly higher than that at 4 ℃ Significantly lower than 4 ℃ (except for 21 d). PoGAMYB4 increased at 25 ℃ and increased at 4 ℃, but decreased at 4 ℃ after sowing for 3 days. PobZIP The trend of expression was similar to that of ABA, and the treatment at 4 ℃ was significantly higher than that at 25 ℃. Therefore, the germination of peony seeds was presumed to be regulated by GA and ABA. GA promoted the seed germination by regulating the signal transduction key genes PoGAMYB4, PoGID1a and PoGAI, of which PoGAMYB4 and PoGID1a might be regulated by GA and PoGAI by GA negatively. PobZIP inhibits seed germination.