【摘要】 以Ｇａｍｂｏｒｇ’ｓＢ＿５培养基为基础，附加激素２，４－Ｄ０．５ｍｇ／Ｌ，ＫＴ０．０５ｍｇ／Ｌ，分别以拟南芥菜的胚、根、子叶、下胚轴、营养期和开花期莲座叶为外植体进行培养，均有愈伤组织形成；胚外植体先萌发出子叶和根，接着在延伸的下胚轴上长出愈伤组织。若将上述培养基碳源由蔗糖改为葡萄糖，整个胚外植体都可形成愈伤组织。对莲座叶的培养发现，即使改变２，４－Ｄ浓度为２．０ｍｇ／Ｌ，其它成分和浓度不变，仍有愈伤组织形成。将以上愈伤组织转移到Ｂ＿５＋５ｍｇ／ＬＺｔ＋０．１５ｍｇ／ＬＩＡＡ的培养基上进行植株再生的诱导，结果发现：由不同器官产生的愈伤组织均可形成根和芽。本实验还对莲座叶柄愈伤组织诱导过程进行了半薄切片光镜水平的细胞学观察，发现维管束内残留的形成层细胞和韧皮薄壁细胞首先发生细胞分裂，随后木薄壁细胞及维管束鞘细胞也进行分裂，连续不断的细胞分裂形成愈伤组织。更多还原

【Abstract】 Calli were successfully induced from root,cotyledon,hypocotyl and leaf explants,and fromhypocotyls of mature embryo explants of Arabidopsis thaliana L.on Gamborg’s B₅ medium sup-plemented with 0.05 mg/L kinetin and 0.5mg/L2,4-D.Using glucose as a substitute of a car-bon source for sucrose,better grown calli were produced from all parts of embryo explants.Rosette-leaf explants were insensitive to the concentration or 2,4-D;no matter whether it was0.5 or 2.0 mg/L,callus formation took place very well.By a transfer and seqtiential subcultureof those calli to B₅ medium containing 5mg/L zeatin and 0.15mg/L IAA,plenty of plantlets re-generated through an approach of organogenesis.The expression of their morphogenetic potentialappeared to be affected by the duration of callus culture and the source of explants.The process ofcallus formation in petioles was observed with thick plastic sections of 2 microns under optical mi-croscope.Cells of vascular cambium and phloem parenchyma in vascular bundles divided first,fol-lowed by those of xylem parenchyma and vascular bundle sheath.Repeated cell division led to theformation of calli.更多还原