苹果矮化砧木‘JM7’的组织培养及其离体叶片不定梢再生

以苹果优良矮化砧木‘JM7’ （Malus prunifolia×M. pumila ‘Malling 9’）为试材, 研究了基本培养基对试管苗增殖生长的影响、蔗糖浓度对试管苗生根的影响及基本培养基、细胞分裂素种类和浓度对离体叶片不定梢再生的影响。结果表明： 基本培养基MS比QL显著提高增殖梢数, 但QL比MS更有利于获得健壮生长的绿苗。3%蔗糖浓度比2%的不定根发生速度快。叶片不定梢再生最适宜的基本培养基是QL。在QL培养基上, 6-BA和TDZ对离体叶片不定梢再生率的影响无显著差异, 但6-BA诱导产生的不定芽在不定梢诱导培养基上可直接伸长生长形成不定梢, 而TDZ诱导产生的不定芽需转移到不加TDZ而加低浓度6-BA的培养基上形成伸长生长的不定梢。

Tissue Culture and Shoot Regeneration from in Vitro Leaf Explants of Apple Dwarfing Rootstock Cultivar ＇JM7＇

A good apple dwarfing rootstock cultivar ＇JM7＇ （Malus prunifoliaxM, pumila ＇Mailing 9＇） was selected as material. Effects of basal medium on shoot proliferation and sucrose concentration on in vitro rooting were examined. Effects of basal medium, the kinds and the concentration of cytokinin on shoot regeneration from in vitro leaf explants were investigated. Results showed that basal medium MS significantly improved shoot proliferation than that QL, but stronger shoots were obtained on QL than on MS. The concentration of 3% sucrose improved the process of root initiation than that of 2%. The optimal basal medium for shoot regeneration from leaf explants was QL. When using QL as basal medium, the effects of TDZ and 6-BA on the percentage of shoot regeneration didn＇t show significant difference. However, adventitious buds from 6-BA were able to directly elongate and develop into shoots on shoot regeneration induction medium （SIM）, whereas adventitious buds from TDZ was unable to elongate and develop into shoots on SIM, it was necessary to transfer the buds to the medium lacking TDZ but containing·Low concentration of 6-BA to form shoots.