猛禽类跗跖骨形态特征与功能的分析

以捕获猎物为生的猛禽类。其跗跖骨具有：骨骼粗壮,肌肉附着槽、血管孔发育,位于同一平面的3个跖骨滑车组成了典型的“滚轴模式”,第Ⅱ跖骨滑车翼延伸变粗等形态特征。这些特征与猛禽类抓握有力、撕裂迅猛、行动稳健的功能相适应,将有利于猛禽类功能的发挥。进一步表明了猛禽类形态特征与其功能之间相互协同、适应性,并以此同地栖性鸟类的“三角模式”相区别。由此可以为古鸟类依据跗跖骨的形态特征来判断其类型及栖息习性提供依据,同时对研究早期鸟类功能演化起到重要的借鉴作用。     

猛禽类15种鸟类线粒体tRNA基因序列及二级结构的比较研究

利用PCR方法扩增13个猛禽类物种线粒体基因组中3个主要的tRNA基因簇：IQM(tRNA^lle-tRNA^gln-tRNA^Met)、WANCY(tRNA^Trp-tRNA^Ala-tRNA^Asn-tRNA^Cys-tRNA^Tyr。)和HSL(tRNA^His-tRNA^Ser(AGY)-tRNA^Leu(CUN)),测序后结合GenBank已登陆的游隼和普通鵟相应序列探讨猛禽类共15种鸟类的分子系统进化。3个目的片段长度分别为212～214bp、353～362bp、205～208bp,通过比较这些tRNA基因序列和二级结构差异,发现可变核苷酸位点占47％,这些变异中67％出现在环区,且存在插入和(或)缺失。茎区相对保守,其中一些变异如双链的互补性碱基突变、G-U配对等对于维系tRNA二级结构的稳定性非常重要。以夜鹰为外群分别构建了15个猛禽类物种共11个线粒体tRNA基因全序列和茎区序列的NJ树和MP树．其中基于全序列的系统发育树分支具有较高的自引导值,因此该数据集所反映的猛禽类系统发育关系可能更接近真实水平。系统发育分析显示,隼形目鹰科更接近于鸱鹗科而不是隼科,而草鹗科的分类地位也与传统的形态学和DNA-DNA杂交数据的结论存在分歧。比较物种问tRNA基因二级结构发现,部分tRNA基因中的核苷酸插入和缺失特征在科水平具有共同衍征,提示这些特征对于猛禽类科间系统发育关系具有较高的参考价值。     

甘蓝型油菜小孢子培养技术的几项改进

本研究在NLN-16和NLN-13的培养基中分别加入0.1mg/L 6-BA和0.05%的活性碳,结果表明6-BA对小孢子再生胚有明显地促进作用,再生胚的频率比对照增加26枚/皿,经分析达到显著水平;而0.05%的活性碳对小孢子再生胚促进作用不显著。对甘蓝型油菜小孢子培养再生植株的染色体加倍及移栽的研究结果表明,在小孢子培养初期加50mg/L秋水仙碱加倍效率最佳,加倍率达到67.6%。小孢子培养的再生苗移栽至大田后,采用遮阳网覆盖小苗,移栽成活率达到87.6%。 Abstract:The application of microspore culture technique was restricted because of its low frequency of embryogenesis and chromosome doubling.Two methods of enhancing the frequency of embryogenesis were employed in the study,namely,activated charcoal treatment in NLN-13 media and 6-BA treatment in NLN-16 media.The treatment with 0.05% activated charcoal produced 24 embryos per plate,which increased 1.7 embryos per plate,as compared with the treatment without activated charcoal.However,the analysis of T-test showed that it was not significant.After adding 0.1mg/L 6-BA in NLN-16 media,the frequency of embryogeny was 38.3 embryos per plate,and it was 26 embryos more per plate than that of CK.Analysis of T-test is significant.This indicates that 6-BA promotes embryogeny in microspore culture.Adding 50mg/L colchicines in NLN-16 media,the doubling frequency was 67.6%.The plantlets transplanted into field with two methods of light-covered net and plastic films were investigated.A survival rate of 87.6% was obtained using light-covered method whereas 57.7% survived using plastic film method.