| In this study,the differences of pear self-rooted and grafted trees in the growth and fruitage habit,fruit sepal persistence,sugar and acid components and content of fruit,leaf bud chilling requirement and fertilizer absorption and utilization were observed with pear cultivars‘Housui’,’Taizhong No.2’,and ’Dangshansuli’ as experimental materials.Here were the main research results:1.The initial flowering stage of self-rooted trees was 1-2 days earlier than that of grafted trees,but there was no difference in flowering stage for the tested cultivars.The new shoot growth,fruit weight and total number of branches of self-rooted trees were significantly lower than those of grafted trees,while the number of spurs of self-rooted trees was significantly more than that of grafted trees.2.The ratio of fruits without calyx of self-rooted trees was significantly higher than that of grafted trees;and the ratio of fruits without calyx in spurs was significantly higher than that of axillary flower bud in ’Housui’ pears;while ratio of fruits without calyx in low and middle node fruits was significantly higher than that of high node fruits;and it could greatly increase the ratio of fruits without calyx by spraying Mn and B elements during flower bud germination stage and Ca element at full flowering stage.3.It showed no significant differences in sugar and acid components between self-rooted trees and grafted trees for the tested cultivars,but the contents of sorbitol,malic acid and quinic acid in the fruits of self-rooted trees were significantly higher than those in the fruits of grafted trees;while the contents of sucrose,raffinose and citric acid in self-rooted trees were significantly lower than those in the fruits of grafted trees.4.It indicated that the leaf bud cold requirement of the self-rooted trees was significantly lower than that of the grafted trees,and the changes of leaf bud cold requirement in the grafted trees were closely related to the rootstocks,and the correlation degree was as follows:’Housui’ pear trees grafted on Bunge(P.betulaefolia)>Decne(P.calleryana)>Buch(P.pashaia)5.Flush fertilization increased the total potassium content of leaves faster than that of fertilizer spreading;the amount of flushing water applied to a single tree was 100 L;and the effect of single flushing of sufficient fertilizer on the total potassium content of the leaves was better than a small amount of multiple fertilization;but during the early stage of flush fertilization,the effect of increasing the total potassium content of leaves in the grafted trees was better than that of self-rooted trees,while during the later stage of flush fertilization,the effect of increasing the total potassium content of leaves in the self-rooted trees was better than that of grafted trees. |
