The Research Of Growth And Physiology Characteristics Of Bramley’s Seedling Young Trees With Different Rootstocks And Its’ Adaptability To Different Soil Conditions

Using one year old ‘Bramley’ grafted on five rootsocks(Mulus robusta,M.prunifolia,M.prunifolia var.Ringo,M.micromalus,and M.zumi)as tested materials,the difference of growth,photosynthetic,physiological characteristics and the adaptability of ‘Bramley’ young trees to different soil conditions were researched,in order to provide the rootstock selection in propagation and commercial culture of ‘Bramley’ apple with theoretical reference.The indexes such as soluble sugar content,photosynthetic characteristics,root vitality and antioxidant enzymes activities were determined and analyzed in the experiment.The results showed that shoot increment,leaf area,soluble sugar content and root vitality of the plants with the rootstocks of M.robusta and M.prunifolia were significantly or very significantly higher,while the contents of MDA,SOD and POD activity were very significantly lower than that of the plants with other three rootstocks.The contents of Chlorophyll and net photosynthetic rate(Pn)in ‘Bramley’ on M.robusta were the highest in all and that on M.prunifolia var.ringo,M.micromalus,and M.zumi were relatively lower.Of the average subordinate function,‘Bramley’ grafted on M.robusta had the biggest value,with the smallest one for that on M.zumi.Preliminary conclusions can be drawn from comprehensive analysis of the performance of young trees and the indexes obtained in the test that all the ‘Bramley’ young trees with the five different rootstocks can grow normally and the adaptability of the five tested rootstocks can be ranked as Mulus robusta,M.prunifolia,M.prunifolia var.ringo,M.micromalus,and M.zumi based on the growth state of young trees.Shoot increment and leaf area of the young trees grown in clay loam with more gravels and sandy soil were very significantly higher than that of the trees grown in clay loam,with the bigger trunk diameter for the trees grown in clay loam.Pn and root vitality of the young trees were ranked as clay loam with more gravels,sandy soil and clay loam.On the contrary,MDA content and SOD activity of the trees were ranked as sandy soil,clay loam with more gravels and clay loam,with significant difference between the three types of soil.Of the average subordinate function,‘Bramley’ young trees grown in clay loam with more gravels had the biggest value,with the middle value for the trees in sandy soil and smallest one for that in clay loam.There was significant interaction between the rootstocks and the soils to the growth,physiological and photosynthetic characteristics of ‘Bramley’ young trees.Shoot increment,Pn and root vitality of the trees with rootstocks of M.robusta and M.prunifolia var.ringo,grown in clay loam with more gravels,were significantly or very significantly higher than those grown in sandy and clay loams,while the trees with rootstock of M.prunifolia,grown in sandy soil,had relatively higher shoot increments,Pn and root vitality.The activity of antioxidant enzymes varied under different soil conditions.Of the average subordinate function of the activity,the trees grown in clay loam with more gravels and grafted on rootstocks of M.robusta and M.prunifolia var.ringo had the biggest value,so did the trees grown in sandy soil and grafted on rootstock of M.prunifolia.Conclusion can be drawn from comprehensive analysis that ‘Bramley’ young apple tree has relatively strong adaptability to different soil conditions and can grow normally whether in clay loam with more gravels or in sandy loam or in clay loam,of which the clay loam with more gravels is the most suitable soil.‘Bramley’ young tree with the rootstocks of M.robusta and M.prunifolia var.ringo grown in clay loam with more gravels is the best while that with the rootstock of M.prunifolia grown in sandy loam is relatively better combinations of scion,rootstock and soil condition.