稻米淀粉黏滞性(RVA谱)特征值的遗传及QTL定位分析

利用武育粳3号/Aichi 106构建的F2 群体,研究了精米粉RVA谱8个特征值: 最高黏度(peak viscosity,PKV)、热浆黏度(hot paste viscosity,HPV)、冷胶黏度(cool paste viscosity,CPV)、崩解值(breakdown viscosity,BDV)、消减值(setback viscosity,SBV)和回复值(consistence viscosity,CSV)、峰值时间（peak time, PeT）、糊化温度（pasting temperature, PaT）的遗传规律。结果表明, PKV为由微效基因控制的数量性状;HPV、CPV、SBV、BDV、CSV可能是由一对主基因和微效多基因共同控制的数量性状;PeT可能由两对主基因控制,并且还受微效多基因的影响。用热研2号/密阳23构建重组自交系群体,于2005-2006年对稻米淀粉RVA谱8个特征值进行了数量性状基因座QTL定位和分析,两年试验共检测到34个QTL,分布在第1、2、3、4、6、7、8共7条染色体上;两年同时检测到的QTL共8个,其中qHPV6、 qCPV6、 qCSV6、 qSBV6、qBDV6位于第6染色体的Wx基因附近;qHPV2、qCSV2位于第2染色体RM341与RM475标记之间,qCPV2位于RM573与RM250标记之间。第2染色体上与支链淀粉合成有关的两个基因与RVA谱特征值有密切关系。     

利用重测序的水稻染色体片段代换系定位控制稻米淀粉黏滞性谱QTL

 稻米RVA谱是评价稻米蒸煮与食用品质的重要指标之一,发掘新的控制稻米RVA谱QTL对稻米品质改良具有重要意义。利用以粳稻品种日本晴为受体、籼稻品种9311为供体并经高通量重测序的染色体片段代换系群体为材料,在两年两点的环境下对该群体中控制RVA谱特征值的QTL进行了定位分析。通过单因素方差分析和Dunnett多重比较, 分析染色体片段代换系与受体亲本之间相关RVA谱特征值的差异,以两年两点都能检测到的显著差异位点作为稳定表达的QTL。共检测到10个稳定表达的QTL,包括控制峰值黏度的4个QTL qPKV2.1、qPKV5.1、qPKV7.1和qPKV8.1,控制热浆黏度的2个QTL qHPV5.1和qHPV7.1,控制冷胶黏度的2个QTL qCPV5.1和qCPV7.1及控制消减值的2个QTL qSBV2.1和qSBV7.1。在两年两点的检测中10个稳定表达QTL的贡献率介于-31.8%～53.2%,这10个QTL分布在第2、5、7和8染色体上,其中位于第2、5和7染色体上的位点存在一因多效性。     

QTL Mapping for Rice RVA Properties Using High-Throughput Re-sequenced Chromosome Segment Substitution Lines

The rapid visco analyser （RVA） profile is an important factor for evaluation of the cooking and eating quality of rice. To improve rice quality, the identification of new quantitative trait loci （QTLs） for RVA profiling is of great significance. We used a japonica rice cultivar Nipponbare as the recipient and indica rice 9311 as the donor to develop a population containing 38 chromosome segment substitution lines （CSSLs） genotyped by a high-throughput re-sequencing strategy. In this study, the population and the parent lines, which contained similar apparent amylose contents, were used to map the QTLs of RVA properties including peak paste viscosity （PKV）, hot paste viscosity （HPV）, cool paste viscosity （CPV）, breakdown viscosity （BKV）, setback viscosity （SBV）, consistency viscosity （CSV）, peak time （PET） and pasting temperature （PAT）. QTL analysis was carried out using one-way analysis of variance and Dunnett＇s test, and stable QTLs were identified over two years and under two environments. We identified 10 stable QTLs： qPKV2-1, qSBV2-1; qPKV5-1, qHPV5-1, qCPV5-1; qPKV7-1, qHPV7-1, qCPV7-1, qSBV7-1; and qPKV8-1 on chromosomes 2, 5, 7 and 8, respectively, with contributions ranging from -95.6% to 47.1%. Besides, there was pleiotropy in the QTLs on chromosomes 2, 5 and 7.     

稻米淀粉RVA谱特征值与直链淀粉、蛋白含量的相关性及QTL定位分析

【目的】检测到新的控制稻米品质性状相关的QTL并分析各性状间的相关性,为了解控制水稻品质的遗传机理和培育优质水稻品种奠定基础。【方法】利用Sasanishiki×Habataki回交重组自交系(backcross inbred lines,BILs)群体在两个环境下种植的结果,检测与稻米直链淀粉含量、蛋白质含量及RVA谱特征值相关的加性QTL。【结果】表型分析结果显示,Habataki的蛋白含量明显高于Sasanishiki;而除消减值以外其余的稻米品质性状指标,Sasanishiki均高于Habataki。利用BIL群体共检测到加性QTL 42个,其中10个QTL位点在2个环境中均能被检测到,即q PC8、q AC4、q AC10、q PKV2、q PKV7、q HPV7、q CPV1、q BDV4、q BDV7、q SBV7,且q CPV1、q BDV4、q PKV7、q HPV7和q AC10等5个QTL尚未见报道。同时,我们还利用Sasanishiki×Habataki染色体片断置换系(Chromosome segment substitution lines,CSSLs)验证了10个稳定表达的QTL位点。【结论】稻米RVA谱特征值与直链淀粉含量、蛋白质含量之间呈现一定相关性,且控制不同品质性状的QTL之间具有共定位现象。     

优质水稻品种越光(Koshihikari)中控制稻米淀粉RVA谱特征值的QTL分析

利用南京11×Koshihikari RIL群体在南京两年的种植结果,检测与稻米淀粉RVA谱特征值峰值黏度、最低黏度、最终黏度、崩解值、消减值、峰值时间和糊化温度相关加性和上位性效应QTL,并分析其表达稳定性。结果表明,7个稻米淀粉RVA谱特征值在两年中均呈连续分布,且存在超亲遗传现象。共检测到8个具有加性效应的QTL与稻米6项淀粉RVA谱特征值有关,两年中能重复出现的QTL有6个,即qTPV-6、qFPV-6、qBDV-6、qSBV-6、qPKT-6和qPT-6,分别控制最低黏度、最终黏度、崩解值、消减值、峰值时间和糊化温度,两年的平均贡献率分别为46.4%、60.3%、31.1%、71.9%、38.5%和12.4%,而qSBV-8和qPT-5仅在1年中被检测到,环境稳定性差。此外,还检测到5对影响稻米淀粉RVA谱特征值的QTL具有上位性效应,互作既发生在相同染色体上也发生在不同染色体之间,但贡献率较小,且受环境的影响较小。控制稻米淀粉RVA谱特征值的稳定、主效QTL,可为Koshihikari中稻米优良蒸煮食味品质相关基因的育种利用提供基础。     

Genetic relationship between grain chalkiness,protein content,and paste viscosity properties in a backcross inbred population of rice

A backcross inbred line population derived from a cross between Koshihikari and Kasalath was used to dissect the genetic relationship among chalkiness, protein content, and paste viscosity properties in rice in three environments. A total of 11 traits (or parameters) were analyzed, including percentage of grains with chalkiness (PGWC), protein content (PC) and protein index (PI), and eight parameters from the viscosity profile. PGWC, PC and PI were significantly correlated with the paste viscosity parameters. We identified 39 QTLs in three environments; ten QTL clusters emerged. Eight QTLs were consistently detected across the three environments and further confirmed using a set of chromosome segment substitution lines (CSSLs) where Kasalath was used as the donor parent and Koshihikari as the recurrent parent. One and two major clusters on chromosome 6 corresponded to the Wx and Alk loci, respectively. The former was responsible for PGWC and most of the viscosity parameters, and the latter for PI and some viscosity parameters. Particularly, QTL qPI-6.1 was linked with both the Wx and Alk loci. The co-locations of QTLs for PGWC and viscosity parameters and the linkage of qPI-6.1 and qBDV-6 at the Wx locus could be largely responsible for the phenotypic correlations between these traits.     

QTL Analysis for Traits Associated with Feeding Value of Straw in Rice(Oryza sativa L.)

Genetic improvement of the digestibility of rice strew for increasing the utilization of the whole rice plant as feedstuffs is an important way to solve the feedstuffs shortage in southeastem China. To elucidate the genetic basis of the traits affecting the digestibility of rice straw, a rice population of 111 recombinant inbred lines (RILs) derived from a cross of Nekken 2xGaya was used to map the quantitative traits loci (QTLs) for in vitro dry matter digestion (IVDMD), the percentages of nonstructurel carbohydrate (NSC) and acid detergent fiber (exclusive of residual ash, ADFom) in 2005 and 2006. IVDMD was positively correlated with NSC, and negatively correlated with ADFom. A total of 16 QTLs were detected in the two years, and the amounts of variation explained by individual QTLs ranged from 6.9% to 15.5%. Some QTLs for IVDMD and ADFom on chromosome 2 were detected in the two years. On chromosome 2, the interval RM475-RM3515 contained QTLs for IVDMD in the two years and for NSC in 2006 only, while the interval RM3874-RM5305 influenced ADFom in the two years and NSC in 2005 only. At those loci, Gaya contributed favorable alleles to IVDMD and NSC, while Nekken 2 contributed positive alleles to ADFom.     

用糙米粉代替精米粉测定淀粉粘滞性的效果研究

研究了利用糙米粉代替精米粉测定RVA谱的效果,发现用3.0 g的糙米粉测得的RVA谱的最高粘度、热浆粘度和冷胶粘度约是用3.0 g精米粉相应值的76%,而用3.3 g糙米粉测定的RVA谱则基本与用3.0 g精米粉测得的RVA谱相近。在育种中,用糙米粉代替精米粉测定RVA谱可节省大量的人力和物力,从而可大大提高早期选择效率。     

Inheritance and QTL Mapping of Salt Tolerance in Rice

An F2 population derived from the cross between Jiucaiqing (japonica) and IR36 (indica) was used to analyze the inheritance of salt tolerance in rice by genetic model of major-genes plus polygenes, and to map the corresponding QTLs by SSR molecular markers. Rice plants of P1, P2, F1 and F2 at 5- to 6- leaf stage were treated under 140 mmol/L NaCI for 10 days. Three indices representing the ability of salt tolerance of rice seedlings were measured, including salt tolerance rating (STR), Na^ /K^ ratio in roots and dry matter weight of shoots (DWS). STR, Na^ /K^ and DWS were all controlled by two major genes with modification by polygenes. Heritability of these traits from major genes was 17.8, 53.3 and 52.3%, respectively. The linkage map constructed by 62 SSR molecular markers covered a total length of about 1 142 cM. There were three QTLs detected for STR located on chromosome 1, 5 and 9, two QTLs for DWS on chromosomes 8 and 9, and two QTLs for Na^ /K^ on chromosomes 2 and 6, one on each chromosome respectively. Single QTL accounted for 6.7 to 19.3% of phenotypic variation. Identification method of salt tolerance in rice and breeding of rice varieties with salt tolerance based on molecular markers assisted selection had been discussed.     

不同年份水稻产量性状的QTL分析

分别于2005年和2006年利用热研2号（粳稻）和密阳23（籼稻）为亲本构建的含111个家系的F6和F7重组自交系群体,对单株穗数、每穗颖花数、每穗实粒数、结实率、千粒重和单株产量6个性状进行了QTL分析。两年共检测到分布于7条染色体上的19个QTL,其中2005年检测到10个,2006年检测到14个,两年相同的QTL 5个。大多数性状之间具有显著的表型相关性,相关性较强的性状之间具有较多共同或紧密连锁的QTL。检测到3个控制产量性状的QTL区域存在一因多效或紧密连锁,其中第8染色体上RM5556-RM331区域两年同时检测到控制每穗颖花数、每穗实粒数以及单株产量的QTL。这些QTL为通过分子标记辅助选择提高水稻产量提供了有用信息。     

转抗除草剂基因水稻与亲本的稻米理化特性及主要营养成分比较

对转抗除草剂基因水稻与原亲本稻米的理化特性和关键性营养成分进行了比较,发现在最高粘度、热浆粘度和冷胶粘度等RVA谱特征值上两者有显著差异,但在表观直链淀粉含量、胶稠度和淀粉粘滞特性的崩解值和消减值等淀粉食用品质方面基本相同;在粗蛋白、粗脂肪、总灰分、氨基酸和矿物质等关键性营养成分上不存在显著差异。表明在水稻遗传转化操作过程中,T-DNA插入并未显著改变原亲本的上述品质性状。     

稻米淀粉粘滞性谱特征的表现及其遗传

通过对水稻F[sub]2[/sub]无性系群体及大量品种（系）的RVA谱的测定,研究了稻米淀粉RVA谱的类型及遗传。结果表明：（1）RVA谱可分为A~F六种类型,糯稻的特征图谱为A型,籼稻的特征图谱有B、C、D、E、F五种类型,粳稻有D、E、F三种类型。（2）稻米的表观直链淀粉含量（AAC）不同,RVA谱则不同。稻米的AAC相同,RVA谱也可不同,在低、中AAC类型中,RVA谱的差异能反映品种食味品质的差异。（3）4个杂交稻组合的RVA谱表现出相同的特点,除最高粘度和起浆温度外,其他特征值均介于双亲之间,表明杂交稻米品质改良要求不育系与恢复系的改良同步进行。（4）在F[sub]2[/sub]无性系群体中,RVA谱各特征均呈连续分布,最高粘度是典型的数量性状遗传,热浆粘度、冷胶粘度、崩解值、消减值、回复值都可能是由一对主效基因和若干微效基因共同控制的遗传。     

氮肥追施量对香稻1601品质和淀粉RVA谱特征值的影响

以自育品系香稻1601为材料,研究不同氮肥追施量对其品质和淀粉RVA谱特征值的影响,为探明氮肥施用量与香稻品质关系提供数据支撑。试验结果表明:随着氮肥追施量的增加,稻米蛋白质含量增加,食味品质下降趋势,淀粉RVA谱曲线整体下降,峰值黏度、热浆黏度、冷胶黏度均呈下降趋势,崩解值和消减值先升高后降低,糊化温度和峰值时间无显著差异。相关分析表明,峰值黏度和冷胶黏度与大米蛋白质含量极显著负相关,相关系数-0.889和-0.843,与食味值存在极显著或显著正相关,相关系数0.896和0.763。     

Genetic dissection of grain nitrogen use efficiency and grain yield and their relationship in rice

Breeding for improved grain yield (GY) and grain nitrogen use efficiency (NUE) is an important objective of many rice breeding programs. A better understanding of the genetics of these two complex traits and their genetic relationship is required for more efficient breeding. This study reports the results of a linkage mapping study conducted for these two traits using 127 rice recombinant inbred lines (RILs) derived from the cross of Zhanshan 97/Minghui 63. Phenotypic data were collected under two nitrogen conditions in 2006 and 2007. For NUE, four and six QTLs were identified in 2006 and 2007, respectively. These QTLs were on chromosomes 1, 2, 6, 7 and 11. For GY, nine and five QTLs were detected on chromosomes 1, 2, 7 and 11 in 2006 and 2007, respectively. The phenotypic and genetic correlations between NUE and GY are positive and highly significant. Four genomic regions, including C86-C2340 on chromosome 1, RZ599-R1738 on chromosome 2, RZ471-C1023 on chromosome 7 and R3203-RM20a on chromosome 11, were found to contain QTLs for both NUE and GY. The effects of the co-located QTLs were in the same direction for NUE and GY, providing a genetic basis for the observed positive genetic correlation between the two traits. These genomic regions might be explored for the simultaneous improvement of NUE and GY in breeding.     

基于粳稻F2和F2:6群体的连锁图谱及剑叶性状QTL比较分析

 以粳稻沈农265和丽江新团黑谷 (LTH) 为亲本,分别构建了F2群体和F2:6群体,分析并比较了两群体的遗传信息和控制剑叶相关性状(剑叶长、宽和比叶重)的数量性状基因座。结果表明：1)多数标记在染色体上的顺序相同,但标记间距不同。F2群体中30个标记显著偏离预期的1∶2∶1孟德尔分离比例,13个标记极显著偏离预期的1∶2∶1孟德尔分离比例,其中19个偏向沈农265,11个偏向LTH。F2:6群体中62个标记显著偏离预期的1∶1孟德尔分离比例,38个标记极显著偏离预期的1∶1孟德尔分离比例,其中43个偏向沈农265,19个偏向LTH。偏分离标记共形成10个偏分离区域,其中有6个区域同时出现在两个群体中。2) F2:6群体检测QTL的能力强于F2群体。F2群体共检测到7个控制剑叶性状的QTL (2个控制剑叶长,4个控制剑叶宽,1个控制比叶重),而F2:6群体共检测到17个控制剑叶性状的QTL (7个控制剑叶长,5个控制剑叶宽,5个控制比叶重),其中有4个QTL在两群体中同时检测到,分别是第9染色体上控制剑叶长的qFLL9,第4染色体上控制剑叶宽的qFLW4,第12染色体上控制剑叶宽的qFLW12.1和第6染色体上控制比叶重的qSLW6。其中,控制比叶重的qSLW6 (加性效应值为1.956 mg/cm2),极富研究与应用价值。     

杂交中籼稻稻米RVA的基因型差异及与籽粒充实的关系

以12个杂交中籼稻组合为材料,研究了籽粒充实性状和RVA特征值的差异及RVA特征值与籽粒充实性状的关系.结果表明,不同杂交中籼稻组合间的籽粒充实性状和RVA特征值差异均达到了极显著水平,但所有参试组合的RVA特征值与籽粒充实性状间不存在简单的直线相关.经过动态聚类分析将供试组合分成3类,不同类别杂交稻组合的RVA特征值与籽粒充实性状间的相关性不同.最终粘度、最低粘度越小的类别,最终粘度、最低粘度与籽粒充实度相关越显著；最高沾度越大的类别,最高粘度与籽粒充实指数相关越显著；消减值的绝对值越大的类别,随消减值绝对值的增大,籽粒充实指数显著减小.     

用籼/籼交重组自交系群体构建的分子遗传图谱及其与籼/粳交群体的分子图谱的比较

为了最终实现对籼稻数量性状基因位点 (QTLs)精确定位 ,用一个包含 1 31个系的籼 /籼交重组自交系群体 (F6∶7)构建了分子遗传连锁图谱。该图谱含由 1 1 3个水稻探针、2 8个小麦探针揭示的 1 6 0个RFLP标记和由 5个PstⅠ /MseⅠ引物组合揭示的 78个AFLP标记。群体的杂合性比率接近期望值 ,表明该群体具有正常的遗传结构。在 6个染色体区域观察到标记的偏分离 ,表明即使在亚种内群体中也可能发生标记的偏分离。本图谱的总长度为 1 4 35 8cM ,相邻标记间的平均距离为 6 38cM。由于采用了一套日本水稻基因组计划 (RGP)的RFLP标记 ,使本图谱能与RGP图谱进行比较。结果表明 ,两个图谱上的共同标记所覆盖图谱总长度几乎相同 ;在水稻 1 2条染色体中的 9条表现完全的连锁保守性。此外 ,水稻的第 1号染色体与小麦的第 3组染色体具有很强共线性。但是 ,两个图谱间也存在明显的差异 ,在 1S、1L、4L和 8L 4个染色体臂上发现 4个小倒位 ;除第 5号和第 6号染色体外的其他染色体上共检测到 1 9个新的位点。籼稻亲本间在染色体臂 2S、7S、1 0L和 1 1S 4个区域的RFLP多态性很低或没有 ,从而导致籼稻图谱在这些区域呈现空白。在这个籼稻图谱中 ,未检测到第 1 1号和 1 2号染色体间的重复性。还就稻属在基因组进化中的染     

Identification of QTLs and Validation of qCd-2 Associated with Grain Cadmium Concentrations in Rice

Cadmium(Cd) is one of heavy metals harmful to human health. As rice is the main staple food in Asia and Cd is easily contaminated in rice, the molecular regulation of Cd accumulation should be explored. In this study, a recombinant inbred population derived from Xiang 743/Katy was grown in Cd-polluted fields and used to map the quantitative trait loci(QTLs) for Cd accumulation in rice grains. We identified seven QTLs distributed on chromosomes 2, 3, 6, 7, 8 and 10. These QTLs displayed phenotypic variances of 58.50% and 40.59% in 2014 and 2015, respectively. Two QTLs, qCd-2 and qCd-7, were identified in both the two years. qCd-2 was detected on the interval of RM250–RM207 on chromosome 2, with an LOD of 2.51 and a phenotypic contribution of 13.75% in 2014, and an LOD of 3.35 and a phenotypic contribution of 14.16% in 2015. qCd-7 co-localized with the cloned qCdT7 on chromosome 7 and may represent the correct candidate. The other five QTLs were detected only in one year. To further confirm the effects of qCd-2, a residual heterozygous line designated as RHL945, with a heterozygous interval of RM263–RM207 on chromosome 2, was selected from the recombinant inbred population and used to develop an F2 population consisting of 155 individual plants. By incorporating further simple sequence repeat markers into the segmental linkage map of the target region, qCd-2 was delimited in the interval of RM5404–RM3774, with an LOD value of 4.38 and a phenotypic contribution of 15.52%. These results reflected the genetic regulation of grain Cd in rice and paved the way for the future cloning of qCd-2.     

玉米主要营养品质性状的QTL定位

以LX00-6×E28的278个F_2:3家系为作图群体,通过SSR标记利用MAPMAKER/EXP3.0和Mapdraw 2.0构建遗传连锁图谱.该连锁图覆盖玉米基因组1 508.1 cM,包含124个标记,相邻两标记的平均距离为12.2 cM.利用QTLMaper2.5软件,结合主要品质性状的检测结果,运用复合区间作图法,以LOD=2.0对玉米主要品质性状进行全基因组QTLs扫描,检测到两个与淀粉含量相关的QTL位点,分别位于第1、8条染色体上,表现为部分显性效应和加性效应,并在第1条染色体上检测到1个与油分含量相关的位点,表现为加性效应.     

两种供氮水平下水稻穗长QTLs的检测

在水稻(IR64×Azucena) DH群体中应用分子标记连锁图,对不同供氮水平下的穗长性状进行QTL区间作图分析。在高氮水平下检测到控制穗长的QTLs 2个,分别位于第1和第4染色体上;在低氮水平下检测到5个穗长QTLs,其中3个分别位于第1、4和6染色体上,2个位于第3 染色体的不同部位,说明穗长QTL与供氮水平之间可能存在交互效应。基于这种互作效应及研究中观察到的两供试亲本对低氮胁迫的耐性差异,推测仅在低氮水平下检测到的穗长QTLs可能跟水稻对低氮胁迫耐性有一定的关联。