利用以籼稻IR24为受体亲本、粳稻Asominori为供体亲本的66个染色体片段置换系，分别与受体亲本IR24杂交构建1套对应的F1群体，研究杂种优势位点。以中亲优势值作为杂种优势QTL检测的基准表型值，结合新构建的基因型图谱，利用QTL IciMapping软件的逐步回归和极大似然估计结合的方法，检测杂种优势QTL。结果表明，各置换系对应的F1群体，在4个环境（2007年南京、2007年南昌、2008年南京、2008年南昌）下，共检测到53个与产量构成性状相关的杂种优势位点。其中只发现1个杂种优势位点能在多个环境重复检测到，即来自第1染色体与标记RM488紧密连锁的位点。该位点在杂合状态下增加F1的株高。22个位点在杂合状态下具有增效作用，占总位点数的41.51%；LOD值变幅为3.06~7.25，贡献率变幅为3.74%~18.5%。31个位点在杂合状态下具有减效作用，LOD值变幅为3.07~9.70，贡献率变幅为0.45%~3078%，这些具有减效作用的位点主要控制单株产量、每穗实粒数和结实率等性状，与籼粳杂种不育基因密切相关。
王智权1，2 ,江玲1,尹长斌3,王晓玲2,雷建国2,肖宇龙2 ,刘喜1 ,刘世家1 ,陈亮明1 ,余传元2 ,万建民1，3，*
. 水稻产量相关农艺性状杂种优势位点的定位[J]. 中国水稻科学, 2013
, 27(6)
: 569
-576
.
DOI: 10.3969/j.issn.1001-7216.2013.06.002
A total of 66 chromosome segment substitution lines, derived from a cross between indica inbred line IR24 (as the recurrent parent) and japonica inbred line Asominori (as the donor parent), were used to investigate the heterotic loci in indica/ japonica intersubspecific rice hybrids. Each line was crossed with the background parent IR24, and the heterosis of F1 hybrids was estimated by comparing the F1 with its two parental lines. Field experiments were carried out across four different environments (2007, 2008 in Nanjing; 2007, 2008 in Nanchang) to evaluate yield and yieldrelated traits in the 66 lines and their 66 corresponding F1 hybrids. Quantitative trait loci (QTL) analyses were conducted using a likelihood ratio test based on the stepwise regression. QTL were detected by statistical software QTL IciMapping using midparental heterosis as basic phenotypic data through a new SSR map. As a result, 53 heterotic loci of yieldcomponent traits were identified with significant effects in different environments. Only one heterotic locus linked closely with marker RM488 on chromosome 1 was detected repeatedly in more than one environment,which might improve the plant height in F1 derivatives. Of all the heterotic loci, 22 (41.51%) showed positive effects, with LOD values ranging from 3.06 to 7.25, explaining 3.74% to 18.5% of the phenotypic variance respetively; 31 loci showed negative effects, with LOD values ranging from 3.07 to 9.70, explaining 0.45% to 30.78% of the phenotypic variance, respectively; Those loci with negative effects mainly affected the traits of grain weight per plant, no. of grains per panicle and seedsetting rate, which were closely related to those genes of hybrid sterility between indica and japonica rice.
\[1\]Mei H W, Li Z K, Shu Q Y, et al. Gene actions of QTL affecting several agronomic traits resolved in a recombinant inbred rice population and two backcross populations. Theor Appl Genet, 2005, 110: 649659.
\[2\]Stuber C W, Lincln S E, Wolff D W, et al. Identification of genetic factors contributing to heterosis from two elite maize inbred lines using molecular markers. Genetics, 1992, 132: 823839.
\[3\]Xiao J H, Li J, Yuan L, et al. Dominance is the major genetic basis of heterosis in rice as revealed by QTL analysis using molecular markers. Genetics, 1995, 140: 745754.
\[4\]Li Z K, Pinson S R M, Paterson A H, et al. Epistasis for three grain yield components in rice (Oryza sativa L.). Genetics, 1997, 145: 453465.
\[5\]Li Z K, Luo L J, Mei H W et al. Overdominance epistatic loci are the primary genetic basis of inbreeding depression and heterosis in rice：Ⅰ. Biomass and grain yield. Genetics, 2001, 158: 17371753.
\[6\]Luo L J, Li Z K, Mei H W, et al. Overdominance epistatic loci are the primary genetic basis of inbreeding depression and heterosis in rice: Ⅱ. Grain yield components. Genetics, 2001, 158: 17551771.
\[7\]Mei H W, Luo L J, Ying C S,et al. Gene actions of QTLs affecting several agronomic traits resolved in a recombinant inbred rice population and two testcross populations. Theor Appl Genet, 2003, 107: 89101.
\[8\]Lu H, RomeroSeverson J, Bernardo R. Genetic basis of heterosis explored by simple sequence repeat markers in a randommated maize population. Theor Appl Genet, 2003, 107: 494502.
\[9\]Syed N H, Chen Z J. Molecular marker genotypes, heterozygosity and genetic interactions explain heterosis in Arabidopsis thaliana. Heredity, 2005, 94: 295304.
\[10\]Li L Z, Lu K Y, Chen Z M, et al. Dominance, overdominance and epistasis condition the heterosis in two heterotic rice hybrids. Genetics, 2008, 180: 17251742.
\[11\]Tang J H, Yan J B, Ma X Q, et al. Dissection of the genetic basis of heterosis in an elite maize hybrid by QTL mapping in an immortalized F2 population. Theor Appl Genet, 2010, 120: 333340.
\[12\]Kubo T, Nakamura K, Yoshimura A. Development of a series of Indica chromosome segment substitution lines in japonica background of rice. Rice Genet Newsl, 1999, 16:104106.
\[13\]Kubo T, Aida Y, Nakamura K, et al. Reciprocal chromosome segment substitution series derived from japonica and indica cross of rice (Oryza sativa L.). Breeding Sci, 2002, 52: 319325.
\[14\]应存山. 中国稻种资源. 北京: 中国农业科技出版社, 1993: 530531.
\[15\]Wang J K, Wan X Y, Crossa J, et al. QTL mapping of grain length in rice (Oryza sativa L.) using chromosome segment substitution lines. Genet Res Cam, 2006, 88: 93104.
\[16\]Wang J K, Wan X Y, Li H H, et al. Application of identified QTLmarker associations in rice quality improvement through a designbreeding approach. Theor Appl Genet, 2007, 115: 87100.
\[17\]Li H H, Ye G, Wang J. A modified algorithm for the improvement of composite interval mapping. Genetics, 2007, 175: 361374.
\[18\]Li H H, Ribaut J M, Li Z L, et al. Inclusive composite interval mapping (ICIM) for digenic epistasis of quantitative traits in biparental populations. Theor Appl Genet, 2008, 116: 243260.
\[19\]McCouch S R. Gene nomenclature system for rice. Rice, 2008, 1(1): 7284.
\[20\]余传元, 万建民, 翟虎渠, 等. 利用CSSL群体研究水稻籼粳亚种间产量性状的杂种优势. 科学通报, 2005, 50(1): 3237.
\[21\]余传源. 水稻籼粳亚种间杂种优势利用的遗传基础研究\[D\]. 南京: 南京农业大学, 2005.
\[22\]王智权. 利用染色体片段置换系剖析水稻籼粳亚种间产量相关农艺性状杂种优势的遗传基础\[D\]. 南京: 南京农业大学, 2010.
\[23\]De Vicente M C, Tanksley S D. QTL analysis of transgressive segregation in an interspecific tomato cross. Genetics, 1993, 134: 585596.
\[24\]Wang Z Q, Yu C Y, Wan J M, et al. Identification of indica rice chromosome segments for the improvement of Japonica inbreds and hybrids. Theor Appl Genet, 2012, 124:13511364.
\[25\]Hua J P, Xing Y Z, Wu W R, et al. Singlelocus heterotic effects and dominace by dominance interactions can adequately explain the genetic basis of heterosis in an elite rice hybrid. Genetics, 2003, 100: 25742579.
\[26\]陈深广, 沈希宏, 曹立勇, 等. 水稻产量性状杂种优势的QTL 定位. 中国农业科学， 2010, 43(24): 49834990.
\[27\]赵芳明, 朱海涛, 丁效华, 等. 基于SSSL的水稻重要性状QTL的鉴定及稳定性分析. 中国农业科学, 2007, 40(3): 447456.
