ABSTRACT
Objective::To study the correlation between endogenous hormone content, related enzyme activity and embryogenesis during the stratification of Acanthopanax senticosus seeds, and to provide theoretical basis for application of endogenous hormones and related physiological indicators in regulating germination of A. senticosus seeds in production and scientific research. Method::Endophytic fungi as well as different concentrations of nitric oxide and hydrogen peroxide solution were used for soaking the seeds of A. senticosus, and then thermophilic stratification was conducted for the seeds. The content of endogenous hormones such as gibberellin (GA3), abscisic acid (ABA), indole acetic acid (IAA), indole butyric acid (IBA) and salicylic acid (SA) in seeds of A. senticosus were tested by high performance liquid chromatography (HPLC), and the activity change of enzymes in vivo such as catalase (CAT), superoxide dismutase (SOD), peroxidase (POD), and malondialdehyde (MDA) were tested. The correlation between the embryo rate and the hormones and their enzyme activities in the seeds of A. senticosus was studied by the grey correlation method. Result::The embryo rate was significantly positively correlated with IAA, GA3, and CAT, with correlation coefficient of 1.086, 0.935 and 1.067, respectively. There was a significant positive correlation between IAA, GA3, CAT, IBA, and SA, but with a significant negative correlation with ABA, MDA, and POD. The correlation degree was as follows: IAA>CAT>GA3>IBA>SA>SOD>ABA>POD>MDA. Conclusion::IAA, GA3 and CAT have significant promoting effects on embryo rate, and there is a significant correlation between hormone content and enzyme activity, which provides a basis for exploring the seed germination mechanism of A. senticosus.
ABSTRACT
Objective: To investigate the effect of exogenous nitric oxide (NO) on breaking the dormancy of Acanthopanax senticosus seeds and the changes in endogenous hormones and enzymes,and provide a basis for breaking the dormancy as well as artificial cultivation of A. senticosus seeds.Method: Different concentrations (1,5,10,20 mmol·L-1) of sodium nitroprusside (NO donor) were used to treat the A. senticosus seeds, and then thermophilic stratification was conducted. The content changes of endogenous hormones such as gibberellin (GA3), abscisic acid (ABA),indolo acetic acid (IAA),indolo butyric acid (IBA) and salicylic acid (SA) at different stratification time (0, 30, 50, 80, 100,130 d) were tested by high performance liquid chromatography (HPLC). The activity change of its in vivo enzymes[catalase (CAT), superoxide dismutase (SOD), peroxidase (POD), and malondialdehyde (MDA)] were tested by enzyme-labeled instrument.Result: In the seed germination process of A. senticosus,the contents of GA3,IAA,IBA,and SA were increased gradually,while the content of ABA was reduced gradually. The enzyme activities of POD and MDA were significantly reduced,and the enzyme activities of CAT and SOD were increased obviously. Exogenous NO could increase the seed germination rate and shorten the seed germination time. The effect of 20 mmol·L-1 sodium nitroprusside showed the most obvious effect and 10 mmol·L-1 SNP showed the weakest effect in promoting seed germination,showing an obvious "V" shape for changes.Conclusion: Sodium nitroprusside could promote the seed germination effect of A. senticosus, probably by increasing the content of hormones and enzyme in the stage of seed germination and improving the contents of endogenous NO during germination.