【摘要】 以耐盐碱郑58和盐碱敏感昌7-2为亲本,构建包含151份F2:5重组自交系(RILs)群体。基于3K芯片对郑58、昌7-2及其F2:5家系进行基因型分析,构建了包含1407个SNP分子标记的高密度遗传连锁图谱。该图谱的各染色体标记数在84～191之间,标记间的平均距离为0.81 cM。胁迫液为200 mmol L–1 NaCl和100 mmol L–1 Na2CO3,对照液为蒸馏水或霍格兰营养液,对盐、碱胁迫和自然条件下玉米的发芽率(GP)、株高(PH)、植株干、鲜重(FW、DW)、幼苗组织含水量(TWS)、植株地上部分钠含量(SNC)、钾含量(SKC)、钠/钾含量比(NKR)、苗期耐盐率(STR)、耐碱率(ATR)10项指标,采用3种不同的作图方法同时定位研究,对加性QTL定位采用复合区间作图法(CIM)和完备区间作图法(ICIM),对加性QTL与环境互作联合分析采用混合线性模型的复合区间作图法(MCIM)。结果表明,(1)与对照条件下各性状表型值相比,耐碱相关性状的降低较耐盐相关性状明显,说明玉米对碱胁迫更加敏感和碱胁迫对玉米的伤害更严重。碱与盐胁迫下SKC相当而SNC差异较大,表明Na+、K+的吸收和运输是相互独立的两个过程,玉米盐、碱胁迫可能是两种性质不同的胁迫。(2)在自然、盐和碱胁迫条件下,运用CIM分别检测到27、28、40个加性QTL;运用ICIM分别检测到28、23、17个加性QTL;运用MCIM共检测到11个耐盐加性QTL、4个环境互作QTL以及11个耐碱加性QTL、3个环境互作QTL。(3)盐胁迫条件下的qPH-9、qSTR-8、qNKR-6、qNKR-7和碱胁迫条件下的qPH-9、qATR-3能被3种作图方法重复检测到。与前人结果比较, qPH-9、qSTR-8、qNKR-6、q-ATR-3定位在相同或邻近区域,qNKR-7尚未见报道。本研究结果为精细定位玉米耐盐碱主效基因、挖掘候选基因和开发用于标记辅助选择的实用功能标记奠定基础。更多还原

【Abstract】 The recombinant inbred line(RIL) F2:5 population was derived from a cross between Zheng 58 tolerant to alkaline stress and Chang 7-2 sensitive to alkaline stress.By using the 3 K chips,the high-density genetic map with 1407 SNP markers was constructed.The number of markers on 10 chromosomes ranged from 84 to 191,and the average physical distance between two markers was 0.81 cM.The germination percentage(GP),plant height(PH),fresh weight(FW),dry weight(DW),tissue water content(TWC),shoot Na+ concentration(SNC),shoot K+ concentration(SKC),shoot K+/Na+ ratio(NKR),salt tolerance rating(STR),or alkaline tolerance rating(ATR) were measured under 200 mmol L–1 NaCl solution of salt stress,100 mmol L–1 Na2 CO3 solution of alkaline stress and the normal water or full-strength Hoagland’s nutrient solutions irrigation as control conditions.The additive quantitative trait loci(QTLs) analysis was conducted by using the composite interval mapping(CIM) and the complete interval mapping method(ICIM),the additive and epistatic QTL × environment interaction effects were analyzed by using the mixed composite interval mapping method(MCIM).Compared with the normal condition,the alkaline stress decreased the tolerance more significantly than the salt stress.Maize was more sensitive to the alkaline stress.The harm of alkaline stress on maize was more serious.The SKC was comparable,but the SNC had great difference for alkaline and salt stresses indicating that the uptake and transport of Na+ and K+ were independent and salt and alkali were two different kinds of stresses.Under normal condition,salt stress and alkaline stress,27,28,and 40 additive QTLs were respectively detected by CIM,and 28,13,and 17 additive QTLs were respectively detected by ICIM.By using MCIM,a total of 11 additive QTLs and 4 QTL × environment interaction QTLs for salt tolerance-related traits,as well as a total of 11 additive QTLs and 3 QTL × environment interaction QTLs for alkaline tolerance-related traits were detected.The QTLs qPH-9,qSTR-8,qNKR-6,q NKR-7 for salt tolerance and qPH-9,q-ATR-3 for alkaline tolerance were repeatedly detected by three mapping methods.After comparing the physical positions of these QTLs with those previously reported,we found qPH-9,qSTR-8,qNKR-6,and q-ATR-3 were located in the same or adjacent position,but qNKR-7 was newly reported.The present study provides a good basis for mapping major genes,mining candidate genes and developing practically functional markers applied in the improvement of salt and alkaline tolerance-related traits in maize.更多还原