| This paper compared the germination rate, measured the water content the contents of proline, free amino acid, soluble protein, MDA, IAA, ABA, GA and ZR, determined the vitality of SOD,POD,CAT of full buds, the peeled bud scales and leaf primordium after full illumination(15℃,20℃,25℃) and cold temperature treatment(0d,20d,40d,60d,80d), using the branches of the central parts of 4a Platanus acerifolia as materials. Three treatments were needed to the buds on these branches (branch of full buds, branch of peeled bud scales, branch of removing leaf primordium).1) Under natural conditions, the average relative water content in winter buds of Platanus acerifolia is high between October 5 and December 5 and the range is small. A small rise tendencies appears after 1-20 Under different low temperature treatment, the order of relative water content is 15℃>18℃>12℃.Under15℃the change isn't obvious in each period.2)Under natural conditions,the average germination percentage of the branches with no central buds and no bud's sacle is the highest under the 25℃illumination ,which is 97.22% and 98.89% respectively. While the highest for branches with full buds is 15℃illumination. In general,Three treatment's germination percentage is the highest when the temperature is 15℃. The order is 15℃>18℃>12℃.At the same time, the germination percentage order of branch with full buds and with no bud's sacle is 80d>60d>40d>20d when the amounts of low temperature days are different.,while for branch with no central buds it is 60d >80d >40d>20d.The treatment under15℃is the most advantageous to winter buds'germination. Moreover the order is 15℃>20℃>25℃3) Under natural conditions, the free Amino acid content of winter bud scale and leaf primordium in Platanus acerifolia show the negativeiy relevant change. Throughout the observation period, the total Amino acid content of leaf primordium is apparently higher than bud scale's. Under different treatment at low temperature, change tendencies of their free amino acids'content are consistent at 15℃,both of which begin rising after 20d ,and become steady gradually after 40d.4) Under Natural conditions, the change trends of Proline content in both Bud scale and leaf primordiu have great similarity, and after 12-05 they maintain at the same level, but the Proline content is higher in the Bud scale than in the leaf primordium .Under the different proceessings at low temperature , the change tendencies of Proline content are relatively consistent,which rise alone with rhe increasing of low temperature treatment.moreover,At the 18℃low temperature treatment,the change tendencies of Proline content in both buds scale and leaf primordium are basically consistent;they both rise at a low temprature of 20d~60d, and drop by a smal margin after 60d.5) Under Natural conditions, the protein content in bud sacle and leaf primordium reach their minimum in 11-20, and mentain at the same level after 12-05, during the observation period, soluble protein content in leaf primordium is larger than in Bud sacle.under Different conditions of low temprature treatment, the soluble protein content in winter bud sacle of Platanus acerifolia rises alone with the low temperature treatment in first days,then gradually become steady.Differently , the soluble protein content in leaf primordium tends to drop gradually after its initial rise.6) Under Natural conditions, the SOD vitality of winter bud sacle and leaf primordiumof Platanus acerifolia tends to increase alternately,besides, the vitality of sod in in winter bud sacle is higher than of leaf primordium under the same conditions.meantime, the POD vitality of leaf primordium is obviously higher than that of Bud sacle,which tends to be steady after 12-05.the trends of CAT vitality of Bud scale and of leaf primordium are basically the same.during the whole period ,the CAT vitality of Bud scale is remarkably higher than that of leaf primordium under the same conditions.during the observation,the MDA vitality of leaf primordium basically stays at the same level of 1.5(μmol?L-1),besides. The MDA vitality of Bud sacle is still higher that of leaf primordium under the same conditions. the SOD vitality of winter bud sacle reduces with the date of cold temperature treatment under different temperatures at 18℃,however ,at 12℃and 15℃it shows no obvious regularity. Numerically,under different treatment of low temperature and illumination,the POD vitality of leaf primordium is remarkbly higher that that of Bud scale,while the SOD,CAT and MDA vigor levels of Bud scale are all higher that those of leaf primordium under the same conditions.7) Under Natural conditions,the tendencies of IAA,GA3 and ZR content of winter bud sacle and leaf primordium of Platanus acerifolia in dormancy is basically the same,which at fiirst reduce during 9-20～10-05, then increase rapidly to reach their maximum at 10-20,afterwards,they reduced quickly and become gentle after 11-05,Differentlty ,the tendencies of ABA content shows two maximums,the ABA content is high between 10-20~11-20, under different treatment of low temperature ,the IAA,GA3 content of winter bud scale of Platanus acerifolia tends is highest under 40d low temperature treatment at 12℃and 18℃,and lowest at 15℃under the same conditions. The tendencies of four hormone levels of leaf primordium is small under the 40d low temperature treatment.besides,the IAA,GA3 and ZR content of leaf primordium are higher that those of Bud scale both under Natural conditions and under low temprature treatment,and only ABA content of Bud scale is higher than that of leaf primordium.8) Under Natural conditions,the tendencies of GA3/ABA,ZR/ABA,IAA/ABA ratios of winter bud sacle and leaf primordium of Platanus acerifolia in dormancy are basically the same, the ratios reduce during 09-20～10-05 and then start to increase, at 10-20,they restore the same level as 09-20.afterwards,the ratios decrease to their mininum in early November.the tendencies of ZR/ABA,IAA/ABA ratios of leaf primordium are basicallly the same,the mininum of which is in 11-05.Differntly,the GA3/ABA ratio is gradually increasing firstly and reduced rapidly afterwards,then gradually increases again. Under the cold temperature treatment of different temperatures, the tendencies of ZR/ABA ratio and IAA/ABA ratio are basically the same,besides, under the cold temperature treatment at 12℃, the tendencies of GA3/ABA,ZR/ABA,IAA/ABA ratios of Bud scale are all the same ,which all increase in the first place ,then reduce ,and increase again. As likewise,the tendencies of GA3/ABA,ZR/ABA,IAA/ABA ratios are basically the same, which gradually increase between 20d~60d and reduced by a small extent. Under the cold temperature treatment at 15℃, the GA3/ABA,ZR/ABA,IAA/ABA raios of leaf primordium tend to reduce after 20d cold temperature treatment and increase afterwards.
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