杨树比较作图及重要性状QTLs定位

【作者】 张博；

【导师】 王明庥； 黄敏仁；

【作者基本信息】 南京林业大学 ， 林木遗传育种， 2005， 博士

【摘要】 本研究基于双拟测交(two-way pseudo-testcross)策略构建了美洲黑杨‘I―69(’Populus. deltoides)×欧美杨‘I―45’(P. euramericana)F1群体分子标记遗传连锁图谱。母本‘I-69’图谱包括462 个标记(164 个SSR、206 个AFLP、83 个RAPD、2 个SNP、6 个ISSR标记和1 个性别分化标记)。共建立29 各连锁群,连锁群图距从9.2 cM~153.9 cM,平均每个连锁群长度60.4 cM;标记间距平均4.04 cM,最大间距21.8 cM,总图距1751cM。父本‘I-45’图谱有包括367 个标记(153 个SSR、142 个AFLP、61 个RAPD、10 个ISSR标记和1 个性别分化标记),共建立28 个连锁群。连锁群图距从11.3 cM~142.6 cM,平均每个连锁群长度58.3 cM;标记间距平均4.83 cM,最大间距22.3 cM,总图距1634cM。基于两图谱之间147 个同源位点,利用JoinMap 软件将亲本图谱进行整合。整合图谱包括652 个标记(225 个SSR、288 个AFLP、120 个RAPD、16 个ISSR、2 个SNP 和1 个性别分化性状),共获得20 个连锁群,最小连锁群25.9cM,最大连锁群图距222cM,平均连锁群图距109.4cM,总图距2078cM;连锁群标记数15～55 个,平均每个连锁群34.3个标记。标记间平均图距3.15cM,最大标记间图距24.8cM。通过110 个同源SSR标记与毛果杨×美洲黑杨(P. trichocarpa×P. deltoides)图谱比较分析,揭示19 对同源连锁群,各个同源连锁群之间存在良好的共线性关系。利用图谱定位了水培和循环营养液培养条件下12 个与生根性状相关的QTLs,并揭示QTLs 位点在根系生长过程中的表达变化过程。定位了3 个杨树抗黑斑病QTLs 位点,并根据杨树基因组序列,共筛选到19 个与抗病相关的候选基因。本研究还首次报道了林木SNPs 标记的开发工作,证明利用公共EST数据开发杨树SNPs 标记是可行的,并成功将2 个SNP 标记定位在遗传图谱上。更多还原

【Abstract】 We report a molecular genetic linkage map for an interspecific F1 hybrid population between Populus deltoides (clone ‘I―69’)×P. euramericana (clone ‘I―45’) by means of two-way pseudo-testcross mapping strategy. A total 462 markers were available for mapping on the maternal tree ‘I-69’, including 164 SSRs, 206 AFLPs, 83 RAPDs, 2 SNPs, 6 ISSRs and one sexual differentiation trait. Twenty nine linkage groups were constructed, map length between 9.2 cM~153.9 cM, which 60.4 cM was average group length. The average interval was 4.04 cM between adjacent markers and the largest is 21.8 cM. A total of 1751cM was observed for the ‘I-69’map. A total 367 markers were available for mapping on the paternal tree ‘I-45’, including 153 SSRs, 142 AFLPs, 61 RAPDs, 10 ISSRs and one sexual differentiation trait. Twenty eight linkage groups were constructed, map length between 11.3 cM~142.6 cM, which 58.3 cM was average group length. The average interval was 4.83 cM between adjacent markers and the largest is 22.3 cM. A total of 1634 cM was observed for the ‘I-45’map. Using 147 homological markers a integrated map was constructed by JoinMap 2.0 software, including 652 markers (225 SSRs, 288 AFLPs, 120 RAPDs, 16 ISSRs, 2 SNPs and one sexual differentiation trait). Twenty linkage groups were constructed, map length between 25.9 cM to 222 cM. A total 2078 cM map length was observed, which average internal is 3.15 cM and the largest internal is 24.8 cM. One hundred and ten homological SSR markers were used to comparative mapping between our map and P. trichocarpa×P. deltoides map. Nineteen homological linkage groups were aligned. And the orthologous markers showed the synteny between the two maps. Twelve QTLs controlling root growth under water or circularly nutrition culture conditions were mapped. Our result also indicated the dynamics of rooting QTLs effect. Three QTLs involved in Marssoniana brunnea resistance were mapped. And 19 candidate resistance genes were identified based on Populus genome sequence. We also first reported SNPs identification in tree species and revealed assembled ESTs from multiple libraries in public database may provide a rich source of comparative sequences to search for SNPs in poplar genome. Two SNPs were mapped in our map.更多还原