Regulation Of Endogenous Hormone And Its Response To Environmental Facters On Seed Germinatin Of Trollius Farreri Stapf

The seed germination is one of the key researches of seed physiology and ecology,which plays an important role in species survival and continuation.Endogenous hormones are considered as a main internal cause to regulate germination and dormancy of seeds among the factors that affect seed germination.In this study,seeds of Trollius farreri Stapf,which is a common specie in the alpine meadow of northeastern Qinghai-Tibet Plateau,were used to explore the regulation mechanism of the dynamics of endogenous hormone content and germination of seeds which were collected from different altitudes with storage condition and storage time,and the changes of endogenous hormones from seed inbibition to germination,to discuss the regulation mechanism of endogenous hormone content on seed germination.The results showed that:?1?The seed germination percentage of T.farreri in the light was significantly higher than it in the dark,and the germination rate of seed at low altitude was significantly higher than it at high altitude.Under the light,the high and low altitude seeds stored at room temperature reached the highest germination rate after 18-month storage,12.67%and54.67%,respectively.While the low altitude seeds reached the highest germination rate?66.67%?at which stored for 30 months.At high altitude,the seed continued to maintain a lower germination rate?0-2.67%?.Under the dark,the high and low altitude seeds stored at room temperature reached the highest germination rate after 12-month storage,4.67%and 46.67%,respectively.And the low altitude seeds stored at 4?reached the highest germination rate?52%?after 12-month storage,and the highest germination rate of the high altitude seeds was 1.33%?12months?.?2?Cold storage is conducive to dormancy of low altitude seeds.Dormancy release is not caused by the rise of the promoters or the decrease of the inhibitors.At room temperature,the germination rate of the low altitude seeds was maintained at a high level after storage time of12-30 months.ZT was stable,and reached at a maximum 0.46 ug.g^-1 after 12-month storage.While GAs and IAA reached the lowest germination rate,319.57 ug.g^-1 and 3.13 ug.g^-1,respectively.The germination rate began to decrease after 30-month storage;IAA reached the maximum for 19.95 ug.g^-1.ABA reached the maximum for 1.07 ug.g^-1 after 27-month storage.At4?,the germination rate of the low altitude seeds was maintained at a high level in stored for30-36 months.ZT had a large fluctuation,and appear the low which stored for 6 or 27 months and the peak which stored 15 or 30 months.GAs kept a decreasing trend and reached the lowest for299.51 ug.g^-1 after 33-month storage.IAA had a greatly fluctuation,and reached the maximum for10.12 ug.g-1 after 15-month storage.Then IAA kept a decreasing trend and reached the lowest value for 3.38 ug.g^-1 after 30-month storage.ABA is always at a low level,and appears the low which stored for 15-30 months and the peak which stored 6-27 months,then presented the opposite trend to ZT.?3?Dormancy of high altitude seed is higher,but the endogenous hormone change with the storage time is similar to the low altitude seed.The content of IAA in the two storage conditions is higher than the low altitude seed;the other endogenous hormone is lower than the low altitude seed.?4?Higher ZT content may be a germination factor,raising the sensitivity of seed to GA and decreasing the sensitivity of seed to ABA.The seed which stored 30 months in 4?began to germinate on the 7th day and the germination rate reached 66.67%in the light.The seed began to germinate on the 9th day and the germination rate reached 39.33%in the darkness.Regardless of light or not,the GAs has been at a high level with the increase of the seed imbibition time,and ABA has been increasing with small amplitude.ZT and GAs has reached the highest level before germination.IAA and ABA has reached the highest level at germination.Both ZT/ABA and GAs/ABA reached the maximum before germination,and then it began to decrease.IAA/ABA decreased rapidly after the imbibition,and then remained at a low level.