莴苣‘红帆’品种下胚轴愈伤组织诱导与植株再生

 莴苣下胚轴愈伤组织诱导时, MS+ 6-BA 0. 5 mg/ L+ 2, 4-D 1 mg/ L+ NAA 0. 1 mg/ L 效果最好,出愈率达94%; 愈伤组织分化为芽时, MS+ 6-BA 1. 0 mg / L+ NAA 0. 05 mg/ L 分化频率最高, 达100% ; 再生苗在1/ 2MS+ NAA 0. 5 mg/ L 中诱导生根成为完整植株。     

培养条件对酸枣叶片不定梢再生率的影响

以酸枣无菌苗叶片为外植体,选用基本培养基ＮＮ６９和ＷＰＭ,外源激素包括ＴＤＺ、ＩＡＡ、ＩＢＡ和ＮＡＡ,暗培养时间为２、３、４周。采用正交实验设计方法,研究了基本培养基、外源激素及暗培养时间对叶片不定梢再生的影响。结果表明在附加ＴＤＺ１~３ｍｇ/Ｌ的ＷＰＭ和ＮＮ６９上都可诱导不定梢再生,但ＷＰＭ比ＮＮ６９更有效。暗培养时间对不定梢再生也有影响,暗培养３周比２、４周更有利于提高叶片的不定梢再生率。在附加ＴＤＺ１ｍｇ/Ｌ、ＩＡＡ０．１ｍｇ/Ｌ的ＷＰＭ培养基上,暗培养３周后转到光下培养,获得的不定梢再生率达８７．５%。     

SSR技术及其在果树上的应用

SSR(Simple sequence repeat)技术以其丰富的多态性、共显性遗传、重复性好和操作简便等优点日益受到重视,已成为植物遗传和育种研究中不可缺少的分子标记。对SSR技术的原理和特点作了简要的介绍,较详细地分析了如何获得SSR引物,特别是综述了果树上SSR引物的研究现状,同时将其与其它几种主要的分子标记进行了比较分析,认为SSR标记检测的位点多态性水平明显高于RFLP,而且重复性优于RAPD;着重介绍了SSR技术在果树种质资源和构建果树遗传图谱及基因定位等研究中的应用现状;指出SSR技术将在果树科研上起到重要的作用。     

Effects of liver regeneration on the proliferation of rat fetal hepatocytes after intrasplenical transplantation

AIM:To study the effect of environment of liver regeneration on the proliferation of rat fetal hepatocytes after intrasplenical transplantation. METHODS:Fetal hepatocytes isolated from 3-week SD rat fetuses bred were transplanted into the spleens of liver regeneration model rats with 70% partial hepatectomy. The cell cycle of the hepatocytes in the remnants liver was analyzed by flow cytometer and the density dimensions of the donor fetal hepatocytes in spleen were measured by image analysis system 7 and 30 days post-transplantation, respectively. RESULTS:Compared with the control group, the proportions of S and G₂ /M cells in the remnants liver were obviously decreased (P＜0.05), but the density dimensions of the donor fetal hepatocytes in spleen increased significantly (P＜0.05) in rats with hepatectomy 7 days post-transplantation. CONCLUSION:The environment of liver regeneration is propitious to the proliferation of fetal hepatocytes after transplantation into spleen.     

Occurrence of Mirafiori Lettuce Virus and Lettuce Big-vein Virus in Relation to Development of Big-vein Symptoms in Lettuce Crops

Big-vein disease (BV) of lettuce has been attributed to infection by Lettuce big-vein virus (LBVV), vectored by the soil fungus Olpidium brassicae. The finding of a second soil-borne virus in lettuce, Mirafiori lettuce virus (MiLV), led to a re-investigation of the role of LBVV in big-vein disease, with evidence emerging that both MiLV and LBVV are vectored by O. brassicae, and that MiLV, not LBVV, is the cause of BV (Lot et al. (2002), Phytopathology 92: 288–293). The two viruses have coat proteins of similar size but have different morphologies and are serologically unrelated. We tested individual lettuce plants in BV-prone fields and protected crops in France and Italy for the presence of the two viruses, using DAS-ELISA and antisera specific for each virus. Both MiLV and LBVV were found at high incidence, often together but sometimes separately. Symptoms were frequently found to be associated with MiLV alone or both viruses, but rarely LBVV alone. However, no absolute correlation emerged, because sometimes MiLV was present in the absence of symptoms, and vice versa. To clarify the situation, individual lettuce plants were examined over a period of time in two further surveys. In surveys of protected crops in France, plants with big-vein were always ELISA-positive for MiLV, or else symptomless plants positive for MiLV were later seen to develop big-vein symptoms. Presence or absence of LBVV appeared to have no effect on symptom development. In surveys of open fields in Italy, all combinations were found: presence of both viruses, apparent absence of both viruses, or presence of each one alone, in plants that developed BV. At the end of the observation period, nearly all plants had BV and contained both viruses.     

肥城桃组培苗诱导、基因转化及其增殖

红里、白里是肥城桃的两个优良品种,但不耐贮藏。为试图利用基因工程解决这一问题,先通过组培将其胚、胚乳、子叶的愈伤组织分别诱导再生植株和芽剥离出茎尖培育成苗。再将肥城桃反义PG基因,通过农杆菌介导转化组培苗,转化苗在含卡那霉素培养基上筛选,获得抗卡那霉素的转基因苗。用研制的增殖培养基培养4～7周,一个苗可生长出14～18分枝的苗,解决了转基因苗获得率低的问题,也满足了对转基因株系进行检测和从组培室到温棚到田间果园过渡栽培和芽接的需求,提高了繁育速率。     

新疆美洲斑潜蝇寄主种类及适合度的调查

通过乌鲁木齐、昌吉等地调查，发现新疆美洲斑潜蝇的寄主植物计有17科55种，其中蔬菜28种(变种)、大田作物8种，花卉和草坪植物13种、野生植物6种。以豆科、葫芦科植物受害最重。应用欧氏距离法的系统聚类分析，研究了美洲斑潜蝇对14种常见寄主植物的适合度；将其划分为5个类型，即最优适宜寄主、良好适宜寄主、适宜寄主、稍次适宜寄主和非适宜寄主。为害虫的防治决策提供了科学依据。     

香蕉分生小球体途径胚性细胞悬浮系的建立

 以7 个香蕉品种未成熟雄花为外植体均获得了分生小球体(meristematic globules) 。分生小球体的诱导率因基因组型和品种而异, 为15 %～81 % , 分生小球体的特点及开始出现的时间也受基因组型和品种的影响。以分生小球体为起始材料, 建立了‘广东2 号’、‘华农7 号’及‘河口龙牙’3 个品种的胚性细胞悬浮系, 并通过体胚发生途径获得了前两个品种的再生植株。     

芥蓝游离小孢子培养初报

 以芥蓝的5个基因型为试材，对游离小孢子培养诱导胚状体发生及植株再生进行了初步探讨。结果表明：供体基因型对成功诱导胚状体发生至关重要；振荡培养明显有利于胚状体的发育；改良MS和B培养基对诱导植株再生没有差别。     

铺散诸葛菜的组织培养及植株再生

 以铺散诸葛菜的叶柄及叶片为外植体, 研究了不同的再生方式。在6-BA 和NAA 配合使用的MS 培养基上, 叶柄和叶片外植体有高的成芽率, 具有强的器官再生能力。在2,4-D 与6-BA、NAA 结合的培养基上, 叶柄和叶片有较高的愈伤组织诱导率, 在含6-BA 的培养基上也易于分化。叶柄、叶片再生的芽和经愈伤组织分化而得来的芽快速繁殖后, 在生根培养基上形成完整植株。研究表明铺散诸葛菜具有极强的器官分化能力。