The Research Of Breaking Dormancy And Germination Mechanism Of Zelkova Schneideriana Seeds

Zelkova schneideriana is one of China's three kinds of ulmaceae zelkova,is class II protected wild plants in China,as the native tree species in recent years more get the favour of greening,landscaping,etc,Z.schneideriana trees form a beautiful rich,strong resistance,the leaf color change makes it able to stand out in the numerous native tree species,the market demand for Zelkova schneideriana is also increasing.Zelkova schneideriana there are two types of breeding,a seed breeding,another for the asexual reproduction,but because of asexual reproduction cost is larger,and no large extension,or in the lower cost of seeding seedlings is given priority to,because the Zelkova schneideriana that sow does not come,storage for a period of time is needed to normal germination,thus to explore the Zelkova schneideriana seed dormancy and germination of lifting mechanism is of great significance to comprehensively analyze the best way to break the Zelkova schneideriana dormancy and the optimum germination conditions,conducive to better promote the Zelkova schneideriana,increase the market supply of Z.schneideriana trees,greatly reduce the cost of Zelkova schneideriana seedling.This topic around the Zelkova schneideriana seeds in jinan area as the experimental material,the optimization of the temperature parameters of the laminated Zelkova schneideriana seeds,physiological and biochemical mechanism and the Zelkova schneideriana seed germination of external factors as the research point,the Zelkova schneideriana seed germination break dormancy and the method and the best time of the most suitable environment parameters,which can rapidly promote the Zelkova schneideriana seed germination.The main research results are as follows:(1)the low temperature and variable Windsor,hidden is conducive to the Zelkova schneideriana seed dormancy,on the parameter optimization,4/20 ? were whisked off to hide the most suitable Zelkova schneideriana seeds,followed by 4 ? hidden,after seeds treated by these two approaches,the highest germination rate can reach more than 60%.On the processing time,4/20 ? were whisked off to hide and 4 ? sand to hide all the processing time for a maximum of 60 d meet requirements in the test conditions,a slight decline after 90 d,4/20 ? can be used in actual applications become Windsor and 4 ? sand,hidden method can deal with 2 months are sprouting.(2)the study of Zelkova schneideriana seeds in 4 ? found hidden inside the material content in the process of change: soluble sugar peaked at 60 d,0 d-60 d continue to rise,soluble sugar content in the process of soluble sugar began to decline after 60 d,explain the seed has been active,to consume soluble sugar for germination stage,the soluble protein in the sand in the process of continuous reduce,continuous decomposed into free amino acids,30 d-the biggest drop in 60 d,the most active seed state.Proline content increased continuously in the process of sand accumulation,with the greatest increase at 60d-90 d.The growth rate of Pro content in the early stage was slower than that in the later stage,indicating that the negative impact on seeds in the later stage began to increase.The content of malondialdehyde increases with the extension of storage time,then decreases and then increases.At 60d-90 d,the content of malondialdehyde is relatively stable,which effectively controls the content of malondialdehyde in seeds.Combined with proline analysis,it can be inferred that most seeds of Z.schneideriana begin to break the dormancy period at about 60 d.The SOD activity first increased 60 d and then decreased slightly with the extension of treatment time.POD began to increase sharply after 60d-90 d,indicating that the antioxidant capacity of Z.schneideriana seeds in the earlier stage was continuously enhanced.The accumulation of peroxides in seeds after 60 d caused the imbalance of internal antioxidant system,which was not conducive to seed germination.Combine the above analysis.Zelkova schneideriana seeds 4 ? sand hidden around 60 d best for germination.(3)through different germination conditions on the Zelkova schneideriana seed germination index impact test analysis available: constant temperature below 15 ? when the Zelkova schneideriana seed germination,when the temperature reached 25 ? seed germination index,the highest temperature 5 ? under the condition of 10 h + 25 ? 14 h Zelkova schneideriana seed germination effect is best,overall warming sprouting effect than temperature sprouting effect is good.Z.schneideriana seeds need dark seeds,and less light(< 8h)can effectively promote the germination of Z.schneideriana seeds.When the relative water content of soil is less than 20%,Z.schneideriana seeds do not germinate,and the optimum soil relative water content is about 60%.When the relative water content of soil is higher than 60%,the germination rate will decline instead.The germination rate of Z.schneideriana seeds soaked with gibberellin(GA3)and cytokinin 6-ba was improved,while the effect of indoleacetic acid(CTK)was not significant.The Z.schneideriana seeds treated with gibberellin(400 mg/L)and 6-BA(40 mg/L)were more suitable for germination.