脐红猕猴桃组培快繁技术研究

以脐红猕猴桃带腋芽茎段为外植体,研究了不同的植物生长调节剂对外植体初代培养、继代培养、生根培养的影响。结果表明,最佳初代培养基为MS+ZT 1.0mg/L+NAA 0.2mg/L,外植体成活率达83.3%;最佳增殖培养基为MS+6-BA 3.5mg/L+NAA 0.2mg/L,增殖系数达4.54;生根率最高的培养基为1/2MS+IBA 0.6mg/L+IAA 3.0mg/L,培养30天生根率95.2%,平均每株生根4.8条。

红脐鳞地衣基因组文库的构建(英文)

地衣是真菌和一种或多种光合微生物形成的稳定的共生联合体 ,既是先锋生物 ,又是敏感生物。环境的变化及生境的片断化 ,使得许多地衣种类处于濒危状态。保护珍稀濒危地衣物种的方法包括地衣体的移植 ,地衣中菌藻的分离培养及基因组文库的构建等。本研究用改进的CTAB方法提取基因组总DNA ,以Lamb daGEM 11为载体 ,构建了红脐鳞 (Rhizoplacachrysoleuca)的基因组文库 ,文库中同时含有该地衣共生菌与共生藻的DNA。该文库包含 8.5× 10 5个重组子 ,插入片段的平均大小为 19kb。文库的容量约为红脐鳞单倍体基因组的 10 0倍。该基因组文库的构建为保护稀有与濒危地衣物种提供了一个新的途径 ,并可进一步开展有关地衣的分子操作研究 ,如地衣冰核蛋白的异源表达等。

不同赤霉素浓度及播种基质对猕猴桃种子萌发的影响

为筛选猕猴桃种子萌发最佳条件,提高萌发速率,缩短育苗时间,以‘脐红’‘金福’为材料,研究不同赤霉素浓度及播种基质对猕猴桃种子萌发的影响。结果表明,促进‘脐红’种子萌发的最佳播种基质为蛭石,赤霉素浓度为500mg/L的发芽率最高,为97%,发芽势为84%。该浓度下种子发芽率、发芽势比其他处理、对照下的发芽率提高2%~39%,发芽势提高3%~33%。促进‘金福’种子萌发宜选择的播种基质为蛭石,赤霉素浓度为250mg/L,其发芽率和发芽势均比其他处理浓度和对照高,分别提高12%~71%、8%~77%。

Dynamic Changes of Sugar Concentrations in Pulp of ‘Cara cara' Navel Orange(Citrus. sinensis L. Osbeck) after Application by Exogenous ABA and GA_3

The dynamic concentrations of glucose, fructose, sucrose and total sugar were determined through exogenous ABA and GA3 treatments during young period of fruit and before fruit coloring in pulp of ‘Cara cara’ navel orange. The results are as fol ows： 10 mg/L ABA increased glucose, fructose and total sugar concen-tration significantly or very significantly, ABA treatment of 50 mg/L increased sucrose concentration very significantly, but ABA treatment of 100 mg/L decreased glucose concentration very significantly. GA3 treatment of lower and middle concentrations（10, 50 and 250 mg/L） increased sucrose concentration very significantly, GA3 treatment of 10 mg/L had no remarkable effect on glucose and fructose concentration but in-creased total sugar concentration very significantly, GA3 treatment of 50, 250 and 500 mg/L decreased glucose, fructose and total sugar concentration very significant-ly. Therefore, ABA treatment of lower concentration could increase one or several kinds of sugar concentration, but GA3 treatment of higher concentration （250 and 500 mg/L） restrained sugar concentration in pulp of ‘Cara cara’ navel orange seri-ously.

Cocultivation of umbilical cord blood CD34^+ cells with retro-transduced hMSCs leads to effective amplification of long-term culture-initiating cells

AIM： To establish a novel coculture system for ex vivo expansion of umbilical cord blood（UCB） hematopoietic progenitors using thrombopoietin （TPO）/FIt-3 ligand （FL）-transduced human marrow-derived mesenchymal stem cells （tfhMSCs） as feeder. METHODS： UCB CD34^＋ cells were isolated and cultured using four culture systems in serum-containing or serumfree medium. Suitable aliquots of cultured cells were used to monitor cell production, clonogenic activity, and long-term culture-initiating culture （LTC-IC） output. Finally, the severe-combined immunodeficient （SCID） mouse-repopulating cell （SRC） assay was performed to confirm ability of the cultured cells to reconstitute longterm hematopoiesis. RESULTS： There were no significant differences in the number of total nudeated cells among different culture systems in serum-containing medium during 21-d culture. However, on d 14, the outputs of CD34^＋ cells, CFU-C and CFU-GEMM in tfhMSCs coculture system were significantly enhanced. LTC-IC assay demonstrated that the tfhMSCs coculture system had the most powerful activity. The severe-combined immunodeficient （SCID） mouse repopulating cell （SRC） assay confirmed extensive ability of the expanded cells to reconstitute long-term hematopoiesis. Furthermore, PCR analysis demonstrated the presence of human hematopoietic cells in the bone marrow and peripheral blood cells of NOD/SCID mice.CONCLUSION： The TPO/FL-transduced hMSCs, in combination with additive cytokines, can effectively expand hematopoietic progenitors from UCB in vitro and the tfhMSCs coculture system may be a suitable system for ex vivo manipulation of primitive progenitor cells under contact culture conditions.