小麥1BL-1RS易位系對赤霉病的影響以及赤霉病抗性突變體的篩選.pdf

1、小麥1BL／1RS易位系對赤霉病的影響以及赤霉病抗性突變體的篩選中文摘要中文捅斐小麥?zhǔn)俏覈匾Z食作物，栽培面積及產(chǎn)量上僅次于水稻和玉米，而我國的小麥長期以來一直受到赤霉病的威脅，小麥赤霉病在我國一半以上的麥區(qū)都有發(fā)生。赤霉病是穗部病害，其發(fā)生導(dǎo)致產(chǎn)量損失，在嚴(yán)重流行年份，減產(chǎn)可達(dá)3050％，除此以外赤霉病的發(fā)生嚴(yán)重影響小麥品質(zhì)和食物的安全性。目前，我國抗赤霉病材料較為單一，抗性資源不足，一旦赤霉病大發(fā)生，將會損失慘重。因此，對小麥種內(nèi)

2、、近緣屬中以及突變體材料中進(jìn)行抗性材料的篩選和鑒定，從中篩選出新的抗病基因，培育出新的抗病材料，是進(jìn)行小麥抗赤霉病育種的關(guān)鍵。在小麥遺傳改良中，黑麥基因是小麥作物育種中最為常見的重要近緣基因資源，尤其以黑麥1R染色體短臂應(yīng)用最為廣泛，該染色體臂上有許多優(yōu)良基因，如條銹病、葉銹病、稈銹病和白粉病等抗性基因，但對于該染色體臂是否介導(dǎo)赤霉病抗性未見報(bào)道。本研究利用1RS的特異分子標(biāo)記Xscm9等在寧7840、Chokwang等材料中檢測發(fā)現(xiàn)，

3、寧7840可能存在1BL／1RS易位，通過基因組原位雜交，證實(shí)中國小麥品種寧7840攜帶1RS，且1RS來源于系譜Aurora。我們通過對寧7840／Chokwang衍生的重組白交系群體(RIL，F(xiàn)13)進(jìn)行單花滴注赤霉病抗性鑒定和基因型分析，結(jié)果顯示，不論Fhbl(Xstsl4)存在與否，攜帶1RS(Xscm9)的株系平均PSS始終比不攜帶1RS(Xscm9)個體的平均PSS小O081，說明1RS所攜帶的某些因子能抑制赤霉病在小麥穗部

4、的擴(kuò)展。方差分析也顯示，F(xiàn)hbl(Ptol05)。關(guān)聯(lián)分析結(jié)果顯示，Xscm9對小麥赤霉病三季的貢獻(xiàn)率分別為01460、01536、O1257，，該位點(diǎn)對于小麥PSS有顯著(PO05)的貢獻(xiàn)。目前，抗性基因單一嚴(yán)重制約小麥抗赤霉病育種工作，誘變育種不僅能產(chǎn)生新的抗病基AbstractWheatisanimportantcrop，secondonlyticeandcominthecultivatedareaandproductionThe

5、wheatinChinahaslongbeenunderthethreatofFusariumheadblight(FHB)，whichhasoccurredinmorethanhalfofthewheat—growingregionsandcaused3050％ofyieldlossesinaseriousepidemicyear，anditalsohadseriousimpactonwheatqualityandfoodsafety

6、duetoDONproductionCurrently，thewell—knownQTLFkblon3BSfromSumai3anditsderivativesisthemajorresistancelocusextensivelyutilizedinbreedingprogramsworldwideSinceFHBresistanceincommonwheatisquantitativelyinherited，withlowtomod

7、erateheritability，andcontrolledbyafewmajorgenesandseveralmodifyinggenesThedevelopmentofFHBresistantvarietieswithgoodagronomicperformanceisstillagreatchallengeeitherbecausemostofQTLwerereportedlytohaveminorand／orinconsist

8、enteffectsonFHBresistance，orthemajorityofvarietieswithgoodFHBresistancehaveunfavorableagronomicperformance，orthefavorableallelesoftheQTLforFHBresistancemaybeassociatedwithyieldpenaltyMutationtechonologyandwheatrelatedrel

9、ativescoulddiversifythegenepoolsandhelpunderstandthemechanismundrelyingFHBresistanceand／orsusceptibilityInthegeneticimprovementofwheat，ryegeneshavebeentheimportantgeneticresourcesforwheatcropbreeding，suchasthestriperust，

10、leafrust，stemrust，andpowderymildewresistancegenesontheshortarmofryechromosome(1RS)However，whether1RSmediatesresistancetoheadscabhavenotbeenreportedInthisstudy，screeningthewheatgermplasmusing1RSspecificmolecularmarkerXscm

11、9demonstratedthatChinesewheatcultivarsNin97840andseveralothercultivarsmightcarry1BL／1RStranslocationGenomicinsituhybridization(GISH)experimentsfurtherverifiedthatNin97840carrieda1BL／1RStranslocation，whichisderivedfromone

12、oftheNin97840’SgenealogyAuroraToinvestigatewhether1RSmediatesFHBresistance，apopulationofrecombinantinbredlines(RIL，F(xiàn)13)derivedfromNin97840／Chokwangwasgenotypedusingmolecularmarkers(including1RS—specificmarkerXscm9)andphe

13、notypedusingsinglefloretinoculationmethod，andtheassociationsbetweenthephenotypesandthegenotypeswereanalyzedTheresultsshowedthat，regardlessoftheFhbl(Xstsl4)locus，theaveragePSSofthelinescarrying1BL／1RS(Xscm9)translocationw