低能N+注入对紫花苜蓿生理生化的影响

研究了低能N^ 注入紫花苜蓿后，对其发芽率，发芽势，苗高，直株重，叶绿素含量，粗蛋白含量以及幼苗过氧化物酶同工酶酶谱的影响，实验结果表明，发芽率，发芽势和过氧化物酶同工酶活性随剂量变化呈现明显的“马鞍型”变化曲线，而且过氧化物酶同工酶酶谱发生变异。     

Pb2 + 和Cd2 + 对日本三角涡虫DNA 损伤及损伤后修复的研究

摘要: 以日本三角涡虫( Dugesia japonica) 为实验材料,采用急性毒性实验研究Pb2 + 、Cd2 + 胁迫下日本三角涡虫体细 胞DNA 损伤情况以及绿豆浸出液对DNA 损伤的保护和修复机制。采用浓度为120 mg /L 的Pb( NO3 ) 2 和1 mg /L 的CdCl2 溶液分别处理涡虫,紫外分光光度法和琼脂糖凝胶电泳检测24 h 后三角涡虫DNA 损伤情况。同时增加 由绿豆浸出液进行修复的2 组对照以研究绿豆对于DNA 重金属损伤后的修复作用和效果。结果表明,Pb2 + 、Cd2 + 胁迫使日本三角涡虫DNA 交联程度增加,并引起DNA 链的断裂; 绿豆浸出液对于由Cd2 + 胁迫引起的DNA 损伤修 复作用较好。而对于Pb2 + 胁迫,在绿豆浸出液与Pb2 + 同时培养的对照组中,推测该浸出液可能使Pb2 + 形成沉淀从 而减小Pb2 + 浓度,因此使DNA 损伤修复具有较好效果,对已经由Pb2 + 胁迫造成损伤的DNA,修复作用不大。     

Characterization of variation induced by low-energy N+ and cloning of differentially expressed cDNA of a mutant in Arabidopsis thaliana

Using Arabidopsis thaliana as experimental materials, the variations induced by low-energy N+ have been investigated. Germination rate of the treated seeds is lower than that of the control, and it decreases with the intensification of the radiation. The phenotypic variations have been observed in M2 plants irradiated with higher doses, such as chlorisis, semilethality, plant morphology, and changes of blooming habit and fertility. In random amplified polymorphic DNA (RAPD) analysis on M2 seedlings, some differences including band deletions or additions are found in treated plants compared to the control and the differences are associated with the radiation doses. One of the M1 plants from the seeds irradiated with the dose of 80×1015 N+/cm2 is a dwarf variant. Its stable M6 generation, mutant T80II, is used to construct subtractive cDNA library and to clone differentially expressed cDNA. A 721 bp cDNA fragment is partly homologous with GRF7 gene.     

离子束介导的小麦低蛋白变异株系NRA、叶绿素含量动态分析

对离子束介导大豆DNA的小麦后代低蛋白质变异株系的旗叶硝酸还原酶活性(nitrate reductase ac-tivity NRA)、叶绿素含量进行分析.结果表明:株系05-49的NRA从抽穗中期至灌浆后期均高于对照,灌浆末期低于对照;株系05-14从扬花中期至灌浆中期均低于对照,灌浆后期至末期均高于对照.叶绿素总含量、叶绿素a和叶绿素b含量,株系05-14在被检测的各时期均高于对照,株系05-49仅在灌浆末期低于对照,其它各时期均高于对照.两变异株系叶绿素a/b值均低于对照.