Effects Of Phellamurin On Dormancy Characteristics And Population Regeneration Of Phellodendron Amurense Rupr.

In order to study the effects of Phellamurin on seed dormancy characteristics and wild population regeneration of Phellodendron amurense Rupr.,the distribution of Phellamurin in various tissues and organs,the content and annual changes of Phellamurin,the effect of environmental temperature and tree traits on the content,and the effect of Phellamurin on the degree of seed dormancy were investigated.To establish the relationship between environmental temperature,Phellamurin content and the degree of Phellodendron amurense Rupr.seed dormancy.Besides,the seed germination and seedling growth of Phellodendron amurense Rupr.under the conditions of Phellamurin contents in natural habitat were studied to determine the effect of Phellamurin on wild population regeneration of Phellodendron amurense Rupr.The results showed that Phellamurin is mainly found in the reproductive and vegetative organs of Phellodendron amurense Rupr.and has the highest content in leaves,flowers,young fruits and pericarp,which can reach 80-110 mg/g.In the leaves,the Phellamurin content was the highest in the budding period,and it continued to decline with the phenophase.The Phellamurin content dropped from the budding to the early fruit period,and the content was the lowest in the deciduous period.In the reproductive organs,the budding period to the early fruit period had a high content,and there was a trend of increasing first and then decreasing at this period.Finally,the content decreased rapidly with fruit development.In the regions with high temperature difference,there was a significant difference in the Phellamurin content in leaves during each phenological periods.The relationship between environmental temperature and the Phellamurin content was negative correlation:when the temperature was lower,the Phellamurin content was higher.In different years at the same site,only partial phenophases has difference in the Phellamurin content,and there is no certain relationship between temperature temperature and the content difference.According to the grey correlation analysis,the most significant factors affecting the Phellamurin content in the budding period to the early fruit period were:minimum daily low temperature,daily mean low temperature,maximum daily high temperature,daily mean high temperature.The PLS results showed that the lower daytime temperature,the warmer nighttime temperature,and the smaller daytime temperature difference favored the synthesis of Phellamurin.The age of trees had a significant effect on the Phellamurin content,and the higher the age,the higher the Phellamurin content;there was no significant difference in the Phellamurin content between male and female plants.The relationship between environmental temperature and the degree of seed dormancy was negative correlation:when the temperature was higher,the degree of seed dormancy was shallower;when the temperature was lower,the degree of seed dormancy was deeper.The low temperature stratification time required for seed dormancy release was significantly higher in Phelloendron amurense Rupr.growing at a lower environmental temperature than that grown at a higher environmental temperature.In the same site,the seed germination rate of the lower environmental temperature years was significantly lower than the seeds of the higher environmental temperature years after low temperature stratification for the same time.In order to determine the effect of Phellamurin on seed dormancy,Phellamurin solution was sprayed to the reproductive organs of Phellodendron amurense Rupr.before and after flowering phase.Harvested seeds were significantly decreased compared with the control in both the germination rate and the germination index.The same treatment to spray wild-type Arabidopsis,compared with the control the seed germination index significantly decreased,the seed germination rate is inhibited,and germination time significantly longer.The results showed that the Phellamurin content had an effect on the seed dormancy,and the increase of the Phellamurin content could lead to a deeper degree of seed dormancy.The continuous detection of Phellodendron amurense Rupr.natural habitat soil for 4 years revealed that the average content of Phellamurin in the habitat soil was in the range of 0.22-45.11 μg/g and the maximum was 58.93 μg/g.The habitat soil without Phellamurin and mixed with Phellamurin monomer and Phellodendron amurense Rupr.deciduous leaves were used to detect the effect of Phellamurin on seed germination ability and seedling growth of Phellodendron amurense Rupr.The results showed that when the content of Phellamurin monomer in the soil was 60 μg/g,the dormancy release and germination of Phellodendron amurense Rupr.seeds were inhibited;in the soil with Phellodendron amurense Rupr.deciduous leaves,when the content of Phellamurin wsa 40 μg/g,the dormancy release and germination of Phellodendron amurense Rupr.seeds were inhibited.The results showed that Phellamurin has adverse effects on the regeneration of wild population of Phellodendron amurense Rupr.,mainly in the aspects of delaying and prolonging the period of maximum seed germination rate,prolonging the seed germination time,reducing the seed germination index,and reducing the dry weight of seedlings.