【摘要】：直立穗型是矮稈和理想株型后水稻適應(yīng)高產(chǎn)要求的重要形態(tài)改良。DENCE AND ERECT PANICEL1(DEP1)是控制穗型直立、每穗粒數(shù)和氮素吸收代謝的多效基因,研究DEP1基因的遺傳基礎(chǔ)和生理作用機(jī)制對水稻高產(chǎn)育種具有重要理論意義和應(yīng)用價(jià)值。為了進(jìn)一步加強(qiáng)DEP1在粳稻以及秈稻中的利用,研究了水稻DEP1基因調(diào)控產(chǎn)量的生理機(jī)制及其與氮高效基因NRT1.1B的聚合效應(yīng),而為水稻高產(chǎn)、超高產(chǎn)和氮高效育種提供分子遺傳依據(jù)和育種技術(shù)指導(dǎo)。結(jié)果如下:1.粳稻品種DEP1多態(tài)性及其與穗部性狀的關(guān)聯(lián)分析分析72份高產(chǎn)粳稻品種DEP1序列多態(tài)性發(fā)現(xiàn),在DEP1序列全長7158 bp的范圍內(nèi),存在著45個(gè)SNP和26個(gè)InDel,據(jù)此進(jìn)行劃分的7種DEP1單體型中分別存在1個(gè)InDel和1個(gè)SNP具有較高的突變頻率,分別是第五外顯子637bp缺失和12bp插入突變和啟動(dòng)子區(qū)域-1254bp處G/C突變。在72份水稻品種中,DEP1第五外顯子637bp缺失和12bp插入突變將導(dǎo)致穗型直立,啟動(dòng)子區(qū)域-1254bp處G/C突變將導(dǎo)致一個(gè)siteⅡ轉(zhuǎn)錄調(diào)控元件的核心序列發(fā)生改變。通過關(guān)聯(lián)分析表明,該G/C等位變異對水稻一次枝梗數(shù)、二次枝梗數(shù)和每穗粒數(shù)存在較大的影響。由此表明,在DEP1啟動(dòng)子區(qū)域發(fā)生的等位變異也會(huì)使水稻穗部性狀發(fā)生變異。2.DEP1基因?qū)λ咎嫉x及產(chǎn)量、品質(zhì)的影響在低氮和高氮條件下,轉(zhuǎn)dep1基因通過上調(diào)GS1;1、GS1;2和NADH-GOGAT1等氮代謝相關(guān)基因的表達(dá)量使水稻植株的氮素含量和可溶性蛋白含量顯著提高,但由于RUBISCO、PEPC2、PEPC6和PEPC7等碳代謝相關(guān)基因表達(dá)量的下調(diào)導(dǎo)致了水稻的光合速率、淀粉、蔗糖和可溶性糖含量顯著降低。轉(zhuǎn)dep1基因使水稻的碳氮代謝發(fā)生失衡,帶來了籽粒結(jié)實(shí)率差、灌漿速率慢、千粒重低和稻米品質(zhì)下降等不利影響,但由于等位基因dep1具有提高一、二次枝梗數(shù)和每穗粒數(shù)的功能,碳氮代謝失衡并未導(dǎo)致產(chǎn)量的降低。3.D PE與NRT1.1B的聚合對水稻氮素利用及產(chǎn)量的影響從151份RILs株系中分別鑒定出在粳型和秈型遺傳背景的DEP1/NRT1.1B、DEP1/nrt1.1b、dep1/NRT1.1B和dep1/nrt1.1b四種基因型的株系。比較分析發(fā)現(xiàn),低氮條件下粳型遺傳背景的dep1/nrt1.1b每穴穗數(shù)、單株產(chǎn)量、莖鞘氮素含量和硝酸還原酶活性顯著高于dep1/NRT1.1B,而高氮條件下無顯著變化。無論高氮還是低氮條件下,秈稻遺傳背景的dep1/nrt1.1b每穗粒數(shù)、單株產(chǎn)量、莖鞘氮素含量和谷氨酰胺合成酶活性均顯著高于DEP1/nrt1.1b。
[Abstract]:Vertical panicle type is an important morphological improvement of dwarf and ideal plant type. DENCE AND ERECT PANICEL1 (DEP1) is a multi-effect gene controlling panicle erect, grain number per panicle and nitrogen absorption and metabolism. It is important to study the genetic basis and physiological mechanism of DEP1 gene for high yield breeding of rice. In order to further enhance the utilization of DEP1 in japonica and indica rice, the physiological mechanism of DEP1 gene regulating yield and its polymerization effect with nitrogen-efficient gene NRT1.1B were studied. Super high yield and nitrogen efficient breeding provide molecular genetic basis and breeding technical guidance. The result is as follows: 1. DEP1 Polymorphism of Japonica Rice cultivars and its Association with panicle traits DEP1 Polymorphism of 72 Japonica Rice cultivars with High yield was found within the full length of DEP1 sequence of 7158 bp. Among the 7 DEP1 haplotypes divided by 45 SNP and 26 InDel, 1 InDel and 1 SNP had higher mutation frequency, which were 637bp deletion at exon 5 and 12bp insertion mutation and G / C mutation at -1254bp in promoter region, respectively. In 72 rice varieties, the deletion of 637bp and the insertion of 12bp at exon 5 of DEP1 will result in the erect panicle, and the G / C mutation at -1254bp in the promoter region will result in the change of the core sequence of a transcription regulatory element of site 鈪，

本文編號(hào)：2260442