长山药块茎休眠期相关酶活性及内源激素含量变化

Chinese Yam (Dioscorea opposite Thunb.) Dormancy-related Activity and the Dynamic Changes of Endogenous Hormone

以2个长山药栽培品种为材料,从采收到出苗设计了5个时期,研究其块茎内部相关酶活性及内源激素含量的变化,结果表明:休眠期间块茎内淀粉酶和淀粉磷酸化酶活性较低,随着休眠的解除活性逐渐升高;过氧化物酶(POD)和多酚氧化酶(PPO)在块茎深度休眠时活性较高,休眠解除块茎萌动后活性迅速下降,不同品种间以上几种酶的变化趋势基本相同。休眠期间长山药块茎中ABA含量随着休眠的进程而降低,GA3、IAA、ZR(玉米素核苷)含量及GA3/ABA、IAA/ABA比值变化随着休眠的进程而增加,ZR含量变化比较平缓;据酶活性与内源激素含量及比值的变化分析,可推断长山药在贮藏60 d后,休眠开始解除,贮藏150 d左右休眠基本解除,这一时期是块茎由休眠转向发芽状态的一个缓慢破除休眠的过渡时期。因此,在贮藏60 d后(休眠解除启动开始),才可以通过一定措施缩短或打破休眠。

Select two kinds of Chinese Yam（Dioscorea opposite Thunb.）as experimental materials,set up five periods from seedling stage to harvest time,in order to study changes of the enzyme activity and the endogenous hormone content of tuber in two kinds of Chinese Yam.The result shows：The amylase activity and the starch phosphorylase activity in tuber will become lower in resting stage,and the activity gradually rise with the relief of dormancy.The POD activity and the PPO activity are higher in deeper resting stage,but the POD activity and the PPO activity decrease rapidly with the relief of dormancy.The ABA content in tuber of Chinese Yam（Dioscorea opposite Thunb.）will be decreased with the dormancy process advancing,but the content of GA3,IAA and ZR as well as the proportion of GA3/ABA,IAA/ABA will be increasing,the ZR content slow vary.Based on the changes of the enzymatic activity and the endogenous hormones content and proportion,it can be inferred that the dormancy will cease after storing 60 days and basically cease after about storing 150 days,which is thought to be the transition period from dormancy to germination.During this period,apply some proper consistency over the cut tuber,or pre-heat it in a short term,so that to shorten and broken the dormancy.