【作者】 李卫平；

【导师】 罗利军； 陈亮；

【作者基本信息】 华中农业大学 ， 作物生物技术， 2007， 硕士

【摘要】 随着农业和化肥工业的发展，作物施氮量迅速增长，但水稻氮素利用效率随着氮肥用量的增长明显下降。过量施用氮肥直接后果是氮素的利用效率的降低，能源的巨大浪费，更造成严重的环境污染。目前许多科学家都在研究作物氮素营养的遗传改良和栽培管理，以提高作物对氮肥的吸收利用效率，培育高效吸收、利用氮肥的作物品种。本研究在大田环境下，以珍汕97B×HR5的重组自交系群体为材料，对不同施氮量下与氮素高效利用效率相关的9个表型性状进行了上海和海南2年2点的表型鉴定和分子遗传分析，并得到如下结果：表型鉴定结果：对分蘖期的分蘖数、苗高、叶绿素含量进行了多次调查测量，发现这些性状与施氮量成正相关，高低施氮量下的差异显著，特别是分蘖数可作为一个分蘖期氮素利用效率的性状；在成熟期调查了有效分蘖数、每穗颖花数、结实率、百粒重、单株籽粒重等产量相关性状和穗长，它们在高低施氮量处理下都表现出显著差异，高氮处理比低氮处理有更多的有效分蘖数；在地力水平高的上海，低施氮量处理比高施氮量处理有更多的颖花数，而地力水低的海南则相反；结实率基本上是低施氮量处理比高施氮量处理高，结实率与施氮量呈负相关；百粒重对氮肥比较敏感，总的趋势是施氮量增加，粒重下降；穗长在基础肥力水平较高的上海的氮肥处理间无显著差异，在海南则表现为随施氮量增加穗长也增加。各个施氮水平下的QTL定位结果：9个性状，在168个处理的139个中共定位了333个QTL，平均每个处理定位了2.4个QTL。分蘖数：37个处理共检测到90个QTL，分布在除第11号染色体外其它11条染色体上，平均每个处理定位到了2.4个QTL，主要集中在第1、3、4、10号染色体上，低、中、高3种施氮量处理各定位了126、96、111个QTL；苗高：42个处理定位到了108个QTL，主要分布在第1、3、4、5、7、10、12号染色体上，平均每个处理定位到了2.6个QTL；叶绿素含量：15个处理定位到31个QTL，主要分布在第4、6号染色体，平均每个处理定位到了2.0个QTL；单株有效分蘖数：5个处理共定位到16个QTL，分布在第1、2、3、4、7、9号染色体上，平均每个处理定位到了3.2个QTL；每穗颖花数：9个处理定位到了17个QTL，分布在第1、3、4、7、10、12号染色体上，平均每个处理定位到了1.9个QTL，所有定位到的QTL其增效等位基因均来自大穗亲本HR5；结实率：7个处理定位到了14个QTL，分布在第2、3、4、5、9、10、12号染色体，平均每个处理定位了2个QTL；百粒重：11个处理共定位了24个QTL，分布在第1、2、3、4、5、6、10号染色体，平均每个处理定位到了2.2个QTL；单株籽粒重：4个处理定位了9个QTL，分布在第1、5、7、12号染色体，平均每个处理定位到了2.3个QTL；穗长：9个处理共定位了25个QTL，分布在第1、2、3、4、8、9、11)号染色体，平均每个处理定位了2.8个QTL。4次实验都定位到的QTL有4个，与分蘖数相关定位于第3号染色体RM49-RM135区域的QTL、与苗高相关定位于第10)号染色体RM147-RM228区域和定位于第12号染色体RM101-RM277-RM313区域的2个QTL、与百粒重相关定位于第5号染色体RM405-RM574-RM437区域的QTL。QTL定位的成簇现象：大部分的分蘖数、苗高QTL定位在相同或相邻的位置，如第3号染色体RM49-RM135区域，产量构成性状的QTL也往往定位在相同区域，如第5号染色体的RM405-RM574-RM437区域等。氮素利用效率QTL定位结果：以各性状在低高施氮量处理下的表性值之比作为衡量氮素利用效率的指标进行QTL定位，共发现23个与氮素利用效率相关的位点，包括8个相对分蘖率QTL，6个相对苗高QTL，3个相对叶绿素含量QTL。更多还原

【Abstract】 More nitrogenous fertilizers are used nowadays whereas the nitrogen utilizationefficiency (NUE) in rice under field conditions is poor. This results in loss of a costlyinput and accentuates the environmental degradation. Many researchers are focusing ongenetically manipulating the crop plants so as to enhance yields at low inputs of nitrogen.Field experiments were carried with a RIL population at different N level, thephenotype data which related to NUE was surveyed at vegetable stage and productivestage, QTL mapping of these traits is also performed. Some conclusions are obtained:Three nitrogen utility-related traits, tiller number, plant height and chlorophyllcontent were investigated for several times during the vegetable stage. All these threetraits positively responded to N fertilizer increasement. Significant difference was foundbetween N level treatments for the three traits, especially the till number which can be agood trait indicating NUE. Panicle number, spikelet number per panicle, spikelet fertility,hundred grain weight, grain yield and panicle length were surveyed at mature stage.These traits showed significant difference between high and low N fertilizertreatment. There are more panicles in high N treatment than low N treatment. In Shanghai,there are more spikelets under low N treatment for the high-level basal N, whereas thereare more spikelets in Hainan for the poor soil. Spikelet fertility decreased according theincreasement of the application of N fertilizer. Grain weight declined with more Nfertilizer application. Panicle length became longer under high N treatment in Hainanconditions, but no significant difference between different N level in shanghai which hasa high basal N level.QTL for 9 traits under 3 N treatments: 333 QTL were detected on 11 chromosomesfor all 168 treatments. 90 QTL controlling TN were found, mainly on chromosome 1, 3, 4and 10 in 37 experiment treatments. 108 QTL for PH were detected in 42 experimenttreatments. 31 QTL for CC were detected in 15 experiment treatments mainly onchromosome 4 and 6. 16 QTL for PN were detected in 5 experiment treatments. 17 QTLfor SN were detected in 9 treatments and all positive alleles were from HR5 which hasmuch more spikelet than Zhenshan97B. 14 QTL for SF were detected in 7 treatments. 24QTL for HGW were detected in 11 treatments. 9 QTL for GY were detected in 4treatments. 25 QTL were detected in 9 treatments. 4 QTL were found in Shanghai andHainan for 2 years, containingl QTLfor TN located between RM49 and RM135 onchromosome 3, 2 QTL for PH located between RM147-RM228 on chromosome 10 andRM101-RM277-RM313 interval on chromosome 12, 1 QTL for HGW among RM405-RM574-RM437 on chromosome.Clustering of QTL controlling different traits: most QTL for panicle number andplant height were detected in the same chromosome regions, such as the marker intervalon chromosome 3 where QTL for panicle number and plant height were found in 14 and11 experiment treatments, respectively. QTL for yield components such as HGW and SFwere co-located in chromosome interval RM405-RM574-RM437.QTL for NUE: 26 QTL for NUE were detected, consisting of 8 QTL for relativetillering, 6 QTL for relative PH, 3 QTL relative CC.更多还原