Effects Of Root Restriction On The Development Of Young Apple Trees And Related Physiological Mechanisms Research

This experiment was to study the effect of root restrictions on the growth characteristics of young apple trees.Three-year-old apple young‘T337'/Malus prunifolia were used as experimental materials.In this research,other materials were four rootstock-scion combinations;3 years 'Huimin shortfu' and ' Nagafu No.2.' were used for scions,M7 and T337 for interstocks and Malus prunifolia for rootstock in container.Study on the effects of different scion combinations on the growth and leaf-related physiological indices of young apple trees.Through the determination of different growth indices and the changes of leaf,carbohydrate and total nitrogen,phosphorus and potassium in the growth process,the suitable method of root restriction and the difference between the rootstock-scion combinations were obtained.The main findings are as follows:(1)The experiment was subjected to root restriction in four methods: ZD(root pruning),ZY(transplanting),DY(transplanting with root pruning)and WFB(transplanting with nonwoven fabric root restriction cultivation),and the control is the trees without any treatments.The root restriction cultivation significantly in habited the growth of young apple trees.But it can increase the number of fibrous roots,root surface area,root volume and root tip number,the content of leaf ratio leaf,total N,P and soluble sugar increased,and the content of soluble total sugar in the leaves was increased by 57.38% and 39.22% respectively.In addition,the appropriate root restriction treatment inhibited the growth of shoots in the shoots,but promoted the development of root system,the root length,total surface area,root volume and root tip were significantly increased,so that the sugar,N,K cumulative increase,which is conducive to saplings from vegetative growth to reproductive growth faster.(2)There were significant differences in plant height,stem diameter and short branch ratio of young tree with different rootstock scion combinations in container.The height of T337 was significantly lower than that of other rootstock combinations,but the number of short shoots was significantly higher than other combinations.The plant height,stem diameter,root index and biomass of different rootstocks of M7 were significantly higher than T337.The content of total N and K of the same rootstocks was higher than that of Gala and Nagafu No.2,but the content of total P was higher than that of Huimin shortfu.The content of total N and P in leaves of M7 and T33 leaves of the same varieties and different rootstocks was not obvious,and the total K content was T337>M7.The Huimin shortfu soluble total sugar content of the same rootstocks was significantly improved compare with Nagafu No.2,M7>T337 total soluble sugar content of leaves of different rootstocks.