水稻抗白叶枯病基因Xa4位点跨叠BAC克隆群的构建

水稻白叶枯病抗性基因Xa4已被定位于第11染色体长臂末端的分子标记VG181和L1044之间,并与抗性基因同源序列片段RS13共分离。利用这3个标记筛选IRBB56的BAC文库,共得到128个阳性BAC克隆,其中RS13获得18个阳性克隆,这18个克隆中有4个和6个我隆分别同时为G181和L1044的阳性克隆,选其中的12克隆进行分析,构建了一个从G181到L1044区间的BAC跨叠克隆,全长420kb,并且56M22、106P13和104B153个BAC克隆可覆盖整个跨叠克隆群。这一研究结果为进一步分离Xa4基因打下基础。     

绿豆组织培养物的遗传转化

将绿豆(Phaseolus aureas),蚌埠绿豆,vc27784A,安引5—16号等的种子。消毒处理后,接种于1/2MS 培养基上,获无菌苗。然后取三日龄绿豆子叶、下胚轴;八日龄绿豆上胚轴切段、叶片;十五日龄茎的切段与3850-1103,3850-4农杆菌共培养10分钟,洗净吸干,培养在无抑制剂(头孢霉素)的诱导培养基(BA 0.5 IAA 1.0mg)上预培养4天,然后转入含头孢霉素量1000μg/ml 的诱导培养基上,其中3850-4转化的部分组织块移入不含 BA 的诱导培养     

Genetic mapping of a new semi-dwarf gene, sd-t(t), in indica rice and estimating of the physical distance of the mapping region

Application and functional study of dwarf and semi-dwarf genes are of great importance to both crop breeding and molecular biology. A new semi-dwarf gene, sd-t(t), non-allelic to sd-1, had been identified in an indica rice variety, Aitaiyin 2. In this study the gene was genetically mapped by using an F2 population, which consisted of 474 individuals developed from a cross between Aitaiyin 2 and B30. The sd-t(t) gene was located between the RFLP markers R514 and R1408B with a distance of 1.1 cM to R514, and 4.5 cM to R1408B on chromosome 4. A physical contig covering the sd-t(t) mapping region was further constructed by screening a BAG library with R514 and R1408B as probes, and the physical distance between R514 and R1408B was estimated at approximately 147 kb. This result will facilitate map-based cloning of the sd-t(t) gene.     

复合诱变筛选产细胞壁水解酶木霉菌株及产酶条件的优化

利用复合诱变技术 ,筛选到一株产几丁质酶和葡聚糖酶能力较强的绿色木霉菌株(Trichodermaviride)LD 1 8。并对其产酶条件进行了优化 ,发现在麸皮∶诱导物∶麦秸粉 =2∶2∶7的固体培养基上 ,以 4g/L (NH4) 2 SO4为氮源 ,起始pH8 0 ,经 2 5℃培养 72h ,产生的真菌细胞壁水解酶 ,用以溶解食用菌、黑曲霉等丝状菌丝体的细胞壁 ,制备原生质体 ,效果较优。     

莴苣及其变种果实的电镜观察

利用扫描电镜对安徽省栽培的莴苣Lactuca sativa及其变种的果实进行观察,结果发现涡阳县义门镇特产的苔菜既不同于莴笋L.sativa var.angustata,也不同于莴苣,应将其建立在莴苣种下作为新变种苔菜L.sativa L.var.yemensis X.S.Shen et R.L.Lu var.nov.更为合适。     

光对稀脉浮萍叶状体群体分离的抑制效应(简报)

长日（16h光照，8h黑暗）与短日（8h光照，16h黑暗）条件下，稀脉浮萍6746群体在暗期的增殖率大大高于光期的，而叶状体增殖率在光期和暗期无显著不同。     

叶肉细胞原生质体培养再生植株变异的研究

为了满足社会对经济作物在数量及质量上不断提高的要求,寻找克服远缘杂交不亲和性及定向改变植物遗传性状的新途径,以培育出适合要求的优良品种,一直是生物学工作者努力的一个重要方面。近来年的研究结果表明,熟练地掌握植物原生质体培养的技术和方法,对于利用原生质...     

Laser-induced tobacco protoplast fusion

Laser tweezers can manipulate small particles, such as cells and organdies. When coupling them with laser microbeam selective fusion of two tobacco protoplasts containing some chloroplast was achieved. Physical and biological variables that affect laser trapping and laser-induced fusion were also discussed. The results show that the effect of chloroplast content and distribution on the yield of cell fusion is remarkable.     

平阳霉素(争光霉素A_5)对艾氏腹水癌细胞核酸代谢及其作用机制之探讨

艾氏腹水癌小鼠腹腔内注入平阳霉素1/6半致死剂量,腹水癌细胞DNA合成受到抑制。随注入药物时间之延长,DNA合成呈直线下降。但在同一剂量和时间条件下,对腹水癌细胞RNA合成率没有影响。通过放射自显影和MPV II显微分光光度计,测定了S期细胞百分数和单个S期细胞中~3H-TdR放射自显影银粒,说明DNA合成率之抑制不是由于S期细胞百分数之降低,而是由于单个S期细胞中DNA合成强度之下降。进一步用MPV II显微分光光度计对同一S期细胞中放射自显影银粒和孚尔根萤光定量测定,发现平阳霉素能引起早S期细胞积累;同时早S期细胞DNA合成抑制也较为明显。说明早S期细胞对平阳霉素较为敏感。其机制可能与早S期细胞合成之DNA富含GC组分有关。这与博莱霉素优先和富含GC组分的多聚核苷酸结合的结果是一致的。