| Tree peony originated in China. After long periods evolution,it is conditioned to grow in the temperate zone, blossoms in spr ing,flower bud differentiats in summer and autumn and leaves falls off during dormancy in winter.Although tree peony is very beautiful and looked as the best of all the flowers,but it's natural florescence is short(about 10 days) and it's blossom concentrats on April or May,so it can not satisfy people's need at a large scale.It has become a subject which people always study that how to make it blossom in other seasons in one year, especially in Spring Festival.According to tree peony's ecological behaviour and blossom characteristic,the methods that make it blossom in Spring Festival which is earlier than it's natual florescence by compositive plant technique is called"the press culture technique of tree peony",also called as "tree peony forcing culture"in custom.The process of tree peony forcing culture is divided into three par ts:choice of the focing culture plant,dormancy release in time,management of adjusting temperature,humidity and light, among these dormancy release is most important.Traditional methods concerns with drying the roots in the sun,daubing hormone on the flower buds etc to release dormancy,the fault of this method which depends on scathe outside,adversity with part of chilling is:the flower buds can not get enough chilling in natural environment and release the dormancy completely,so it often leads to small flower,no flower or leaf even failure of focing culture.To determine the chilling requirment of tree peony is a very imperative subject.In addition,although we have summarized many experience on the planting technique, we know little about the physiological and biochemical changes in this process, especially the relationship between chilling and nutrition substance and hormones of plant.This experiment studied on the chilling requirment,some physiological and biochemical changes during dormancy release and focing culture in greenhouse of four representative cultivars cv.Da Hu Hong,cv.Wu Long Peng Sheng and cv.Rou Fu Rong.We pointed out the chilling requirment at the first time,explained the important effect of certain chilling on dormancy and forcing culture in greenhouse from the point of physiological and biochemiscal changes.The results are as follows:1.A certain amount of chilling is the effective way for tree prony to release dormancy, chilling has desicive effect on dormancy release,no chilling or absence of chilling lead to failure of dormancy release or not complete dormancy release,the plant can not blossom or blossom abnormally in green house.Use 7.2℃model,0~7.2℃model and utah model respectively to calculate the chi lling requirment of cv.Da Hu Hong,cv.Yin Hong Qiao Dui,cv.Wu Long Peng Sheng and cv.Rou Fu Rong,the results are: cv.Da Hu Hong: 544,536,715 chilling unit; cv.Yin Hong Qiao Dui:481,473,595 chilling unit;cv.Rou Fu Rong: 502,487,596 chilling unit;cv.Wu Long Peng Sheng: 639,602,762 chilling unit.2. The content of souble protein and free amino acid had obvious rule in change during dormancy release. Souble protein of flower buds was low at the beginning of dormancy,then rose gradually with the accumulation of chilling,reached the top at the moment dor mancy released,then dropped;souble protein of roots was less than that of flower buds,but free amino acid of it was more than that of flower buds;free amino acid had the reverse change with souble protein in flower buds.The content of souble protein and free amino acid was a measure of the procession of dormancy release.3. During dormancy release, with the accumulation of chillin g,souble sugar of flower buds and roots rose gradually, souble sugar of flower buds reached the top before dormancy released;the starch of roots was always more than that of flower buds and branch, but starch of flower buds present reverse trend with souble sugar before dormancy released.The content of souble sugar and starch of branch were always very low and no obvious...
|
PDF Full Text Request