Studies On Storage Nourishment Of Pear Tree In Dormancy Period

This paper took Yali pear,Whangkeumbae pear,Xuehuali pear,and Bayuehong pear as experimental matrial. The changes of storage nourishment of tree and the distribution condition in annual shoot were studied during the period of dormancy , in order to supply the theory reference for cultivation of good quality and high yield. The main results were as follows:The changes of storage nourishment of Yali pear of different patterns all showed the same certain law. The variation law of storage nourishment of off-lying developmental branch and short branch were the same.The contents of soluble sugar first raised, later dropped and then raised. The soluble sugar of stem xylem reached the top contents in the last of January,while the top contents of stem phloem, blossom bud and growth bud all in the middle of January. The contents of starch first dropped and then raised. The trendency showed inverse relationship with that of the soluble sugar. The minimum content of stem xylem appeared in the last of January, while the minimum contents of stem phloem, blossom bud and growth bud all appeared in the middle of January.The changes tendency of protein contents of bud were inconcordance with that of stem xylem and stem phloem except ascending before germination, showed the tendency of decreased first and ascend later, the maximum contents were in the middle of January, the minimum contents were in the last of January. The changes tendency of amino acid contents of bud showed inverse relationship with that of the stem xylem and stem phloem, showed the tendency ascend first decreased later and ascend last, the maximum contents were in the last of January. The amino acid contents showed the same tendency of stem xylem and stem phloem, decreased first and asend later, the minimum contents were in the middle of January.The changes of P contents of stem xylem decreased during the period of dormancy, the tendency of that of P almost not changed, but the maximum contents of different types of shoots were in the middle of January. The changes of P contents of bud showed drastic relatively. It ascend, decreased and ascend, decreased again.The changes of K contents of bud were in the same of that of the stem xylem ,showedthe tendency of ascend first and decreased later, the changes of K contents of stem phloem and stem xylem conversed. The maximum content of bud was in the last of January, the maximum content of stem xylem was in the middle of January, while the minimum content of stem xylem was in the middle of January.The changes of phenols of buds, stem phloem and stem xylem were the same, first raised then dropped , and growth bud reached the top contents in the last of January, blossom bud,stem phloem and stem xylem reached the top contents in the middle of January. The storage nourishment contents of vigorous tree was greater than weak tree, these can supply firm foundation for hibernation and growth, development in the next year.The storage nourishment contents of the short fruit shoots were higher than the middle fruit shoots, the middle fruit shoots were higher than the long fruit shoots, the short developmental branch was higher than the middle developmental branch, the middle developmental branch was higher than the long developmental branch, the short fruit shoots were higher than the short developmental branch, the middle fruit shoots were higher than the middle developmental branch, the long fruit shoots were higher than the long developmental branch. The main storage position of soluble suger, protein, K and phenols was stem phloem. The stem phloem and stem xylem both are the main storage position of amino acid. The main storage position of starch was stem xylem. The main storage position of P in the early dormancy period was stem xylem too. The main storage shape of carbon nutrition was starch, The main storage shape of nitrogen nutrition was protein.