红色西洋梨品种‘红星’的组织培养及离体叶片不定梢再生

Tissue culture and shoot regeneration from leaf explants of red-skinned cultivar ‘Starkrimson’ of Pyrus communis

以优良红色西洋梨(Pyrus communis)品种‘红星’为试材,研究了基本培养基和外源植物生长调节物质对试管苗增殖和生根的影响,并以离体材料叶片为外植体,研究了植物生长调节物质和碳源对叶片不定梢再生能力的影响。结果表明,细胞分裂素6-苄氨基嘌呤(BA)可促进试管苗腋芽的增殖,但常伴有绿梢顶端肥胖或顶端枯死等生理异常现象;噻苯隆(TDZ)可促进无菌苗的伸长生长及叶片的伸展增大,绿苗生长健壮,但增殖率低。BA和TDZ组合使用可诱导无菌苗既有良好的增殖生长又有较好的状苗生长。最佳继代增殖培养基为添加0.5mg·L^-1 BA、0.2 mg·L^-1 TDZ和0.2 mg·L^-1吲哚丁酸(IBA)的QL培养基。相比蔗糖, d-山梨醇做碳源能显著提高离体叶片不定梢再生率。TDZ和BA对不定梢再生的影响因碳源的不同表现出差异,碳源为蔗糖时,不定梢再生率在不同TDZ和BA浓度下均无显著差异;碳源为d-山梨醇时,不定梢再生率在不同TDZ浓度下明显高于不同BA浓度下,但在不同TDZ浓度之间或不同BA浓度之间无显著差异。相比1/4MS无机盐基本培养基,1/2MS无机盐基本培养基能显著提高试管苗生根率;在添加0.3 mg·L^-1萘乙酸(NAA)的1/2MS无机盐培养基上生根率最高,达91.0%。

European pear(Pyrus communis) cultivar ‘Starkrimsom’ with good quality and red skin was selected as material. The effects of basal media and exogenous plant growth regulators on proliferation and rooting of in vitro shoots were examined. In vitro leaves were also selected as explants. The effects of plant growth regulators and carbon sources on shoot regeneration was investigated. Results showed that cytokinin 6-benzylaminopurine(BA) promoted axillary proliferation of in vitro shoots, but hypertrophy and necrosis were seen infrequently in shoot. Thidiazuron(TDZ) produced low proliferation rate of in vitro shoots, however, it promoted elongation growth of in vitro shoots and expanding growth of leaves. The combination of BA and TDZ produced both proliferation and elongation of in vitro shoots. The optimal subculture proliferation medium was QL with 0.5 mg·L^-1 BA, 0.2 mg·L^-1 TDZ and 0.2 mg·L^-1 indolebutyric acid(IBA). For shoot regeneration from leaf explants, d-sorbitol significantly improved regeneration rate than sucrose. The effects of TDZ and BA with various concentrations on shoot regeneration were different depending on carbon sources. When sucrose as carbon source, shoot regeneration rate didn’t show significant difference between TDZ and BA or among different concentrations of these two regulators. When d-sorbitol as carbon source, shoot regeneration rate with TDZ was significantly higher than that with BA, but there was no significant difference between different concentrations of TDZ or BA. Basal medium 1/2 MS with inorganic salts significantly improved rooting rate of in vitro shoots than 1/4 MS with inorganic salts. The highest rooting rate(91.0%) was achieved on 1/2 MS with inorganic salts and 0.3 mg·L^-1 1-naphthylacetic acid(NAA).