水稻恢复系C224对条纹叶枯病的抗性遗传模型分析

应用植物数量性状"主基因+多基因混合遗传模型"方法分析了C224对条纹叶枯病抗性的遗传效应,并考查了C224与7个保持系组配的杂交组合对条纹叶枯病的抗性。结果表明,C224对条纹叶枯病的抗性遗传符合2对加性-显性-上位性主基因+加性-显性多基因的混合遗传模型(E-1),两对主基因的加性效应分别为-12.47和-24.75,均呈负向显性,上位性和互作效应明显;主基因的遗传率为92.12%,多基因遗传率为2.74%,抗性遗传存在明显的主基因效应。在C224与7个保持系组配的杂交组合中,有5个组合对条纹叶枯病的抗性达到高抗或中抗水平。     

山东省水稻抗条纹叶枯病育种现状与展望

对近年来山东省水稻条纹叶枯病爆发的原因进行了分析,并概述了山东省水稻条纹叶枯病抗性育种的研究现状,指出山东省应进一步加强水稻抗条纹叶枯病育种研究的力度,常规育种与分子育种技术相结合,加快育种进程,以不断满足生产需求和提高对突发病虫害的抗灾应变能力。     

浅谈水稻条纹叶枯病综合防控技术

水稻条纹叶枯病是一种病毒病,主要由灰飞虱传播病毒引起。该病害目前在台安县只是零星发生,但有逐年加重的趋势,已成为台安县水稻生产上不可忽视的重要病害之一。本文重点介绍了水稻条纹叶枯病的发病机理和综合防控技术,以帮助稻区农民更好地了解和防治水稻条纹叶枯病,确保水稻丰产、农民丰收。     

8个水稻品种的条纹叶枯病抗性特征

利用强迫饲毒、集团接种、非嗜性测验、抗生性测验的方法研究与分析了8个抗条纹叶枯病水稻品种对条纹病毒和介体灰飞虱的抗性,发现不同水稻抗性品种的抗性特征并不完全相同。IR36、Kasalath、窄叶青8号、道人桥、DV85既抗条纹病毒又抗介体灰飞虱,对条纹叶枯病所表现的抗性是条纹病毒和介体灰飞虱抗性共同作用的结果; 爱知97和Kenta Nakan抗条纹病毒,但不抗介体灰飞虱,对条纹叶枯病所表现的抗性是品种对条纹病毒的抗性;而IR24对条纹病毒和介体灰飞虱仅表现中等抗性。     

水稻品种（系）抗白叶枯病性的田间评价

１９８６－１９９２年，对１０９２份水稻品种（系）于田间进行了抗白叶枯病性的人工接种和自然诱发鉴定，从中筛选出一批抗丰兼优良种，可为育种和生产部门因地制宜地择优利用。     

浅谈水稻条纹叶枯病综合防控技术

水稻条纹叶枯病是一种病毒病,主要由灰飞虱传播病毒引起。该病害目前在台安县只是零星发生,但有逐年加重的趋势,已成为台安县水稻生产上不可忽视的重要病害之一。本文重点介绍了水稻条纹叶枯病的发病机理和综合防控技术,以帮助稻区农民更好地了解和防治水稻条纹叶枯病,确保水稻丰产、农民丰收。     

水稻抗白叶枯病微效QTL的定位分析

以不携有抗白叶枯病主效基因的中感籼粳双亲(窄叶青8号和京系17）及其花培DH群体为材料,接种白叶枯病菌浙9612后,考察了该DH群体的白叶枯病抗性,并进行了数量性状座位（QTL）分析。共检测到控制白叶枯病的4个QTL,分别位于第3、4、5和6染色体上,其中第3和第4染色体上的qBBR-3和qBBR-4,其加性效应为正值;而位于第5和第6染色体上的为负值,4个QTL的总效应是38.6%。方差分析和差异显著性比较表明,具有4个QTL抗性等位基因水稻株系的白叶枯病抗性与不含QTL抗性等位基因的株系相比,差异达极显著水平（P<0.01)。说明通过微效基因的聚合可以获得对白叶枯病的一定抗性。     

谈防治水稻条纹叶枯病的体会

近几年来,天津、唐山、秦皇岛一带稻区水稻条纹叶枯病病情加重,给水稻生产造成了较大影响。病害症状特点为稻苗上部叶片自基部开始,上可至叶片端部下可至叶鞘褪绿黄化,持续发病,田间前期零星发生而后期成片发生(均为随机分布型)。用药剂防治难度较大,适当推迟水稻播种和插秧期,适当增加插秧密度,可减轻发病程度,但解决这一病害的主要出路在于推广种植盐丰47和津原45等抗病的水稻品种。     

不同水稻品种条纹叶枯病抗性筛选

通过田间抗病性鉴定,不同水稻品种条纹叶枯病发病率存在差异。与对照嘉991相比,HZ586等4个品种未见发病,属高抗品种;台03216、宁04—05发病率低,抗病性好;粳制07等8个品种发病率较低,抗病性较好;浙大510等20个品种发病相对较重;绍糯04—46、嘉粳3648等5个品种发病率最高,为感病品种。对田间灰飞虱虫量与带毒率测定结果表明,水稻品种间发病率与田间灰飞虱虫量和带毒率有密切关系。     

水稻灌浆期耐热害的数量性状基因位点分析

 利用由98个家系组成的Nipponbare / Kasalath // Nipponbare回交重组自交系群体及其分子连锁图谱，以粒重感热指数\[（适温粒重-高温粒重）/适温粒重×100\]为评价指标，采用混合线性模型的QTL定位方法，对水稻灌浆期耐热性的主效、上位性数量性状基因位点及其与环境的互作进行分析。共检测到3个灌浆期耐热性主效QTL，分别位于第1、4和7染色体上，LOD值为8.16、11.08和12.86，贡献率8.94%、17.25%和13.50%。其中位于第4染色体标记C1100-R1783之间的QTL，没有显著的上位性和环境互作效应，表明在不同环境和遗传背景中的表达较为稳定，在水稻耐热性育种中可能具有较大的利用价值，其耐热性等位基因来自亲本Kasalath，高温热害时可减少粒重损失3.31%。位于第1染色体标记R1613-C970之间的QTL和第7染色体标记C1226-R1440之间的QTL，耐热性等位基因来自亲本Nipponbare，分别可减少粒重损失2.38%和2.92%。这两个QTL均具有与环境的互作效应，其中第7染色体上的QTL还和其他基因位点有互作。检测到8对加性×加性上位性互作QTL，分布于第1、2、3、5、7、8、10和12染色体上。没有检测到上位性QTL与环境的互作效应。     

Quantitative Trait Loci for Resistance to Stripe Disease in Rice （Oryza sativa）

In order to map the quantitative trait loci for rice stripe resistance, a molecular linkage map was constructed based on the F2 population derived from a cross between Zhaiyeqing 8 and Wuyujing 3. Reactions of the two parents, F1 individual and 129 F2:3 lines to rice stripe were investigated by both artificial inoculation at laboratory and natural infection in the field, and the ratios of disease rating index were scored. The distribution of the ratios of disease rating index in Zhaiyeqing 8/Wuyujing 3 F2:3 population ranged from 0 to 134.08 and from 6.25 to 133.6 under artificial inoculation at laboratory and natural infection in the field, respectively, and showed a marked bias towards resistant parent (Zhaiyeqing 8), indicating that the resistance to rice stripe was controlled by quantitative trait loci (QTL). QTL analysis showed that the QTLs detected by the two inoculation methods were completely different. Only one QTL, qSTV7, was detected under artificial inoculation, at which the Zhaiyeqing 8 allele increased the resistance to rice stripe, while two QTLs, qSTV5 and qSTV1, were detected under natural infection, in which resistant alleles came from Zhaiyeqing 8 and Wuyujing 3, respectively. These results showed that resistant parent Zhaiyeqing 8 carried the alleles associated with the resistance to rice stripe virus and the small brown planthopper, and susceptible parent Wuyujing 3 also carried the resistant allele to rice stripe virus. In comparison with the results previously reported, QTLs detected in the study were new resistant genes to rice stripe disease. This will provide a new resistant resource for avoiding genetic vulnerability for single utilization of the resistant gene Stvb-i.     

粳稻垩白性状的QTL检测

 利用大粒粳稻DL115与小粒粳稻XL005杂交获得的F2群体200个单株为作图群体,采用复合区间作图方法,利用SSR标记对稻米垩白性状进行了数量性状基因座(QTL)检测。研究结果表明,稻米垩白粒率、垩白大小和垩白度在F3株系均呈连续分布,表现为由多基因控制的数量性状。检测到与稻米垩白性状相关的QTL 8个,分别位于第3（5个）、第5（2个）和第6（1个）染色体上,包括与垩白粒率有关的QTL 3个,与垩白大小相关的QTL 2个,与垩白度有关的QTL 3个。其中位于第3染色体RM6832-RM411、RM15456-RM6832和RM6266-RM15456区间的qPGWC3、qACE3b和qDEC3b,分别解释垩白粒率、垩白大小和垩白度表型变异的43.89%、18.83%和19.57%,为主效QTL。上述3个主效QTL所在染色体上的位置与前人研究结果均不一致,认为是新的QTL。所检测到的8个QTL中,除qPGWC6的增效等位基因来自无垩白亲本XL005外,其他7个QTL的增效等位基因均来自垩白性状值较大的亲本DL115。垩白粒率和垩白大小基因作用表现为部分显性,垩白度基因作用表现为加性。     

Quantitative Trait Loci for Mercury Tolerance in Rice Seedlings

Mercury (Hg) is one of the most toxic heavy metals to living organisms and its conspicuous effect is the inhibition of root growth.However,little is known about the molecular genetic basis for root growth under excess Hg2+ stress.To map quantitative trait loci (QTLs) in rice for Hg2+ tolerance,a population of 120 recombinant inbred lines derived from a cross between two japonica cultivars Yuefu and IRAT109 was grown in 0.5 mmol/L CaCl2 solution.Relative root length (RRL),percentage of the seminal root length in +HgCl2 to-HgCl2,was used for assessing Hg2+ tolerance.In a dose-response experiment,Yuefu had a higher RRL than IRAT109 and showed the most significant difference at the Hg2+ concentration of 1.5 μmol/L.Three putative QTLs for RRL were detected on chromosomes 1,2 and 5,and totally explained about 35.7% of the phenotypic variance in Hg2+ tolerance.The identified QTLs for RRL might be useful for improving Hg2+ tolerance of rice by molecular marker-assisted selection.     

水稻种子低氧发芽力的QTL定位和上位性分析

利用35份水稻品种资源,评价了在不同水深、温度等低氧条件下的种子萌发情况,表明水温30℃、水深0.2 m下黑暗萌发5 d为最佳鉴定方法,并以此条件下水稻种子萌发的芽长为鉴定指标,评价了359份水稻品种低氧发芽力地区间、籼粳间的差异。进一步利用81个Kinmaze/DV85 重组自交系群体进行了水稻低氧发芽力数量性状位点分析, 在第1、2、5、7染色体上检测到5 个低氧发芽力QTL,其中第5染色体上存在2个QTL,各QTL的贡献率为10.5%～19.6%。同时进行上位性分析,检测到3对互作位点,分别位于第2、3、5、11染色体上,其中位于第3染色体上标记C563-X182之间的位点与第5染色体上标记R830-X208之间的位点的互作贡献率高达48.78%。     

稻米出饭特性QTL分析及遗传研究

 米粒长、饭粒长和饭粒延伸系数等性状与米饭品质密切相关。以籼稻台中本地1号（TN1）与粳稻春江06为亲本构建的加倍单倍体群体为材料,利用全基因饱和分子标记连锁遗传图谱对多个稻米出饭特性相关的性状进行QTL定位, 共检测到14个QTL。其中,米粒长和米粒浸长QTL各1个,均位于第2染色体上,分别可以解释性状变异的15.20% 和1850%;1个米粒浸泡膨胀率QTL,位于第6染色体上,可解释性状变异的1339%;1个煮饭粒长QTL,位于第9染色体上,可解释性状变异的1360%; 3个蒸饭粒长QTL,分别位于第1、3和12染色体上,共解释性状变异4500%;4个煮饭延伸率QTL, 分别位于第3、6、9和10染色体上,共解释性状变异6130%; 3个蒸饭延伸率QTL分别位于第1、3和6染色体上,共解释性状变异4910%。在已知的Wx和ALK基因所在区域都检测到了米饭延伸性相关的QTL。相比较而言,覆盖ALK基因的QTL对出饭特性的影响更大,LOD值达到了635。该研究结果可为稻米出饭特性相关调控基因的克隆奠定基础,同时对稻米品质的改良及高产优质稻品种的分子标记辅助选育提供理论参考。     

利用近等基因系研究3个抗水稻纹枯病QTL的聚合效应

利用特青/Lemont组合的回交群体,证实了特青第7染色体上存在抗纹枯病QTL qSB7Tq。以Lemont为轮回亲本,通过分子标记辅助连续回交结合性状鉴定,构建了qSB7Tq与另外两个抗水稻纹枯病QTL qSB9Tq（位于特青第9染色体）和qSB11Le（位于Lemont第11染色体）的一套近等基因系,对各抗性QTL的单个效应及其聚合效应进行了研究。3个抗性QTL单独存在或在聚合状态下均能显著提高水稻品种对纹枯病的抗性水平。但是,不同抗性QTL之间可能普遍存在一定的负向互作关系。讨论了一致的遗传背景对QTL研究的重要性,以及不同QTL的聚合效应及互作关系对育种实践的意义。     

水稻抗恶苗病微效QTL的定位

对粳稻品种春江06和籼稻品种TN1以及由它们构建的加倍单倍体（DH）群体,采用芽期接菌方法接种恶苗病菌,进行抗恶苗病微效QTL的定位分析。共检测到2个QTL:qB1和qB10,分别位于第1和第10染色体上,2个QTL的抗性基因都来自春江06,贡献率相近。     

水稻株高QTL及其与产量性状和抽穗期关系的研究进展

株高是一个与水稻品种丰产潜力密切相关的重要性状。主效半矮秆基因背景下的水稻株高变异,一般表现为受多基因控制的数量性状。最近的研究表明,已定位的株高QTL分布于水稻的所有12条染色体,其中4个QTL已克隆。克隆研究和QTL初定位结果表明,株高QTL往往存在对产量性状和（或）抽穗期的多效作用,可利用于提高水稻产量潜力。     

Confirmation of Novel Quantitative Trait Loci for Seed Dormancy at Different Ripening Stages in Rice

Seed dormancy contributes resistance to pre-harvest sprouting.Effects on respective quantitative trait loci (QTLs) for dormancy should be assessed by using fresh seeds before germinability altered through storage.We investigated QTLs related to seed dormancy using backcross inbred lines derived from a cross between Nipponbare and Kasalath.Four putative QTLs for seed dormancy were detected immediately after harvest using composite interval mapping.These putative QTLs were mapped near C1488 on chromosome 3 (qSD-3.1),R2171 on chromosome 6 (qSD-6.1),R1245 on chromosome 7 (qSD-7.1) and C488 on chromosome 10 (qSD-10.1).Kasalath alleles promoted dormancy for qSD-3.1,qSD-6.1 and qSD-7.1,and the respective proportions of phenotypic variation explained by each QTL were 12.9%,9.3% and 8.1%.We evaluated the seed dormancy harvested at different ripening stages during seed development using chromosome segment substitution lines (CSSLs) to confirm gene effects.The germination rates of CSSL27 and CSSL28 substituted with the region including qSD-6.1 were significantly lower than those of Nipponbare and other CSSLs at the late ripening stage.Therefore,qSD-6.1 is considered the most effective novel QTL for pre-harvest sprouting resistance among the QTLs detected in this study.     

Mapping Quantitative Trait Loci for Palatability of Milled Rice

Quantitative trait loci (QTLs) controlling palatability in rice were identified using a set of 98 backcross inbred lines (BILs) population derived from a cross between a japonica variety Nipponbare and an indica variety Kasalath. The palatability scores of the population measured by RQ1/Plus Rice Analyzer, showed a continuous and transgressive segregative distribution with a range from 66 to 92. Four putative QTLs for palatability, qPAL-5, qPAL-7, qPAL-8a and qPAL-8b, were detected on chromosome 5, 7 and 8, and they accounted 7.83, 7.03, 11.58 and 7.19% of the total phenotypic variation, respectively. Three alleles qPAL-5, qPAL-7 and qPAL-8b from Kasalath increased the palatability score, whereas only one Nipponbare allele qPAL-8a increased the score. Eight transgressive lines in palatability were selected to make a comparison between phenotypic and genotypic classes. The result explained the possibility of positive QTLs pyramiding through marker-assisted selection of highly palatable rice.