SH系苹果矮化砧茎尖组培快繁技术研究

从１９８７年开始，以ＳＨ系４个优系为试材，进行了ＳＨ系茎尖组培快繁技术研究。５年研究结果：①筛选出适合分化的１号培养基，有效分化率５０％以上；②４个ＳＨ系优系各自的继代培养基，经过２０～３０代继代培养，增殖倍数稳定在２．９～４之间，正常率９０％以上；③适合ＳＨ系４个优系的生根培养基Ｒ７，生根率９５％以上。此外还改进了传统的外移技术，使外移成活率达８０％以上。

A Study on Rapid Propagating Technique Through Stem Tip Tissue Culture of SH Line Apple Dwarf Stock

SH line apple dwarf stock is developed from Rails x Mains honanensis.As it is of species hybridization with wild male parentage,SH line stock shows stress-resistant. The grafted chimera is dwarfing or semi-dwarfing, early-fruiting, high-yielding,with bright-coloured, fragnant and tasty fruits,so it is a superior dwarf stock in the apple-producing area in North China. Since the low propagating rate through layering of SH line stock. cannot meet the growing demand in production for apple seedlings,it is necessary to develop a rapid propagating technique, such as the SH line stem tip tissue culture. Owing to the heterogeneity of apple trees and the different conditions in various Places, emphasis in the present study is put on the selection of the optimum culture medium,the optimum environment factors and the optinuim transplanting method for the in vitro seedlings. From 1987,using 4 superior SH lines as test material and after 5 years research we have screened (1) No.1 medium, which promotes differentiation,with an effective differentiation rate of over 50%; (2) successive generation culture media for 4 superior SH lines respectively, after 20￣30 successive generations culturee,with a stable propagating rate of 2.9to 4 times,and a normal propagation coefficient of over 90%; (3)R7 culture medium, which promotes rooting for 4 superior SH lines,with a rooting coeffcient of over95%.In addition, we have improved the traditional in vitolr transplanting technique and obtained a survival rate of over 80%.