沙冬青愈伤组织对培养基的特殊要求和球形胚状分化结构的诱导

通过对沙冬青未成熟子叶进行离体培养，获得了愈伤组织。基本培养基采用Ｂ５，再配合ＭＳ培养基的铁盐成分，对沙冬青未成熟子叶愈伤组织的诱导和生长效果最佳。愈伤组织的诱导和生长对培养基的附加成分要求十分严格，２，４－Ｄ浓度为０．５ｍｇ／Ｌ，６－ＢＡ浓度为０．５ｍｇ／Ｌ，蔗粮不宜超过２％。愈伤组织最初为乳白色透明松散状态，生长比较缓慢，极易褐化死亡。如果培养基中的蔗糖浓度低于２％，两周后未成熟子叶愈伤组织逐

SPECIAL DEMANDS OF CALLUS TO MEDIUM AND INDUCTION OF DIFFERENTIATED STRUCTURES LIKE EMBRYOID IN GLOBULAR STAGE IN MONGOLIAN AMMOPIPTANTHUS

Calluses had .induced from segments of immature cotyledons of Ammopiptanthusmongolicus (Maxim.) Cheng f.. The influencements of MS,B5 and N6 as basal media toinduction and growth of calluses were compared. It was suggested that B5 macroele-ments,microelements and organic substances coordinated ferric components of MS hadthe best effect. Demand of callus induction and growth of Mongolian ammopiptanthus toadditional components of medium was very rigorous, concentration of 2, 4-D was 0. 5mg/L,concentration of 6-BA was 0. 5 mg/L,sucrose concentration was not suitable togo beyond 2%. The initial calluses were cream colour, spongy and transparent. Theygrow slowly,browned and died quickly. If the concentration of sucrose was below 2%,the calluses derived from immature cotyledons changed into yellowish gradually andformed many granular structures which were similar to embryoid in globular stage. Cer-tain amount of KH2PO4 (1. 0- 5.0 mmol/L) supplemented in the medium could increasethe rate of calluses which could form granular structures and numbers of granular struc-ture in every callus.