紫云英叶片及叶肉原生质体的培养

本工作研究了豆科植物紫云英的叶片及叶肉原生质体的培养。叶片培养实验表明,诱导愈伤组织的最适培养基为MS加1.0-2.0毫克/升2,4-D和0.25毫克/升KT;诱导根分化需加1.0—5.0毫克/升NAA和0.5毫克/升BA;而苗分化则以0—0.5毫克/升IAA和0.5毫克/升BA为好。高浓度的NAA有利于根分化而抑制茎芽形成;高浓度的IAA对根和芽分化都有抑制作用。叶肉原生质体分离和培养试验表明,紫云英叶肉原生质体的释放及其培养活力受叶龄、植株生理状态和酶浓度的影响。叶肉原生质体在改良的KM8P培养基中能分裂。用改良KM8细胞培养基定期稀释,可使分裂持续进行而得到细胞团。BA和2,4-D为诱导紫云英叶肉原生质体分裂所必需。其最佳组合激素为BA 0.21毫克/升和2,4-D 1.13毫克/升。葡萄糖作为渗透压稳定剂时,其浓度明显影响原生质体的存活率。弱光条件下培养比黑暗培养有利于叶肉原生质体分裂。由叶肉原生质体形成的愈伤组织能形成瘤状结构和根。

ON THE CULTURES OF LEAFLETS AND MESOPHYLL PROTOPLASTS OF ASTRAGALUS SINICUS L.

The present report deals with the study on the cultures of leaflets and mesophyll protoplasts of Astragalus sinicus.The results obtained in leaflet cultures showed that the medium con- taining 1.0?.0mg/1 2,4-D and 0.25 mg/1 KT was favourable for callus formation;1.0?.0 mg/1 NAA and 0.5 mg/1 BA,for rooting;0?.5 mg/1 IAA and 0.5 mg/1 BA,for shoo- ting.Higher concentration of NAA promoted rooting but inhibted shoo- ting.However,higher concentration of IAA blocked both rooting and shoo- ting. As to the protoplast culture,the age and physiological condition of leaflets and concentration of enzymes used for protoplast isolation affected the yield and survival of the mcsophyll proto- plasts.The mesophyll protoplasts cul- tured in MS,B5 and their modified media did not divide but did in the modified KM8P media.Sustaining divisions were maintained by diluting the medium with fresh modified KM8 medium periodically,which resulted in the callus formation.BA and 2,4-D are critical factors triggering the divi- sion of the mesophyll protoplasts.It was demonstrated that 0.21 mg/1 BA and 1.13 mg/1 2,4-D was the best combination to initiate the mesophyll protoplasts.Increasing the concentra- tions of 21 kins of amino acids & 4 kins of nucleotide bases to the medium raised the plating efficiency of the mesophyll protoplasts.Glucose added as osmotic stabilizer in the medium influenced survival of the cultured mesophyll protoplasts.To stimulate division,the mesophyll protoplast cul- ture in light was better than that in dark.The callus derived from the mesophyll protoplasts failed to diffe- rentiate shoot but nodular structures so far.However,under different cultural conditions,roots could be regenerated readily from the callus of from the green nodulars produced on the callus.