中国农业科学 ›› 2014, Vol. 47 ›› Issue (7): 1256-1264.doi: 10.3864/j.issn.0578-1752.2014.07.002

• 作物遗传育种·种质资源·分子遗传学 • 上一篇    下一篇

特异玉米种质四路糯的穗行数遗传解析

 焦付超, 李永祥, 陈林, 刘志斋, 石云素, 宋燕春, 张登峰, 黎裕, 王天宇   

  1. 中国农业科学院作物科学研究所,北京 100081
  • 收稿日期:2013-09-29 出版日期:2014-04-01 发布日期:2014-01-03
  • 通讯作者: 黎裕,E-mail:liyu03@caas.cn;王天宇,E-mail:wangtianyu@caas.cn
  • 作者简介:焦付超,E-mail:644291541@163.com
  • 基金资助:

    国家自然科学基金项目(91335206)、国家科技支撑计划课题(2013BAD01B02-3)、农业部农作物种质资源保护与利用项目(NB2130135)、农业部公益性行业科研专项(201303007)

Genetic Dissection for Kernel Row Number in the Specific Maize Germplasm Four-Rowed Waxy Corn

 JIAO  Fu-Chao, LI  Yong-Xiang, CHEN  Lin, LIU  Zhi-Zhai, SHI  Yun-Su, SONG  Yan-Chun, ZHANG  Deng-Feng, LI  Yu, WANG  Tian-Yu   

  1. Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing 100081
  • Received:2013-09-29 Online:2014-04-01 Published:2014-01-03

摘要: 【目的】玉米穗行数与产量密切相关,剖析其遗传基础对指导玉米育种实践具有重要意义。【方法】以只有4行籽粒的中国特异地方品种四路糯选系和多穗行数的自交系农531为亲本,采取单粒传法(single seed descend method, SSD)构建正反交F2:3分离群体。在北京昌平和河南新乡采用随机区组试验设计进行分离群体家系的穗行数表型鉴定。与此同时,根据玉米基因组数据库上公布的标记信息,在全基因组范围内筛选获得173个具有多态性的SSR标记,用于群体基因型鉴定及遗传图谱构建。采用完备区间作图法(ICIM)和复合区间作图法(CIM)进行玉米穗行数QTL定位和遗传效应分析,利用SAS软件GLM程序估计主效QTL对分离群体穗行数遗传变异的贡献率。【结果】表型鉴定结果表明,亲本四路糯选系与农531的穗行数平均值分别为4.0行与19.2行,F2:3家系穗行数变化范围为4.0—17.4行。利用完备区间作图法,分别对北京昌平、河南新乡的正交F2:3群体进行穗行数QTL定位,2个环境下共检测到12个穗行数QTL,分布于除第1、7染色体外的其他8条染色体上。等位变异来源分析表明,本研究定位的QTL减效等位变异全部来自少穗行数亲本四路糯选系。共有5个主效QTL在2个环境下均被检测到,其中,位于bin2.04区间内的主效位点qKRN2-1在单环境下最大可解释群体穗行数变异的18.48%,其余4个主效位点及其单环境下解释的最大表型变异分别为qKRN4-2(11.58%)、qKRN5-1(13.55%)、qKRN8-2(16.91%)和qKRN9-1(9.66%)。利用复合区间作图法,在联合环境条件下共检测到5个穗行数QTL,分布在第2、4、5、8、9染色体上,每个QTL解释的表型变异范围为6.13%—10.05%,除位于第5染色体的QTL以外,其余4个位点与完备区间作图法定位到的主效QTL区间一致。一般线性模型分析显示,在2个环境下,5个主效QTL可分别解释正交F2:3群体51.5%(北京昌平)和54.0%(河南新乡)的表型变异。还定位到2对穗行数上位性QTL位点,分布于第2,、4、9染色体上,但表型贡献率分别仅为2.90%和1.80%。【结论】穗行数减效等位变异全部来自四路糯选系,鉴定出5个玉米穗行数主效QTL,分别位于bin2.04、bin4.09、bin5.04、bin8.05和bin9.03。表明该四路糯选系可作为重要的穗行数遗传研究材料,而定位到的主效QTL可作为玉米穗行数候选基因图位克隆和玉米遗传基础研究的重要候选区段。

关键词: 玉米 , 四路糯 , 穗行数 , QTL , 遗传解析

Abstract: 【Objective】 Kernel row number (KRN) is directly related to maize yield. QTL for KRN was mapped to dissect the genetic basis of KRN, which was helpful to the improvement of yield performance in maize.【Method】In order to dissect the genetic control of KRN of Four-rowed waxy corn, a landrace collected in southern Yunnan, the segregation populations were developed by reciprocally crossing the inbred line derived from Four-rowed waxy corn with Nong531, an inbred with 18-22 rows. The reciprocally crossed F2:3 populations derived from F2 by single seed descend method were separately phenotyped in Beijing (BJ) and Henan (HN). Trials were conducted in randomized complete blocks with two replications. Totally 173 polymorphic SSR primer pairs obtained from the maize genome database (http://www.maizegdb.org) were used to genotype the lines and to construct linkage maps. QTL and their interactions for KRN were detected with ICIM (QTL IciMapping Version3.2 Software) and CIM (QTL Network2.0 Software). The phenotypic variation explained by the major QTL was estimated with SAS GLM software. 【Result】 Phenotypic analysis showed that the average KRN of Four-rowed waxy corn and Nong531 was 4.0 and 19.2, respectively, and the KRN of the reciprocally crossed F2:3 families ranged from 4.0 to 17.4. In two environments, a total of 12 QTL were detected with ICIM, which were located on eight chromosomes. All alleles having negative effect on KRN were from Four-rowed waxy corn. A total of five major QTL could be detected in both environments. qKRN2-1, which was the QTL with the largest effect, explained 18.48% of the phenotypic variance. The other four QTL, which were qKRN4-2, qKRN5-1, qKRN8-2 and qKRN9-1, explained 11.58%, 13.55%, 16.91% and 9.66% of the phenotypic variance, respectively. Five QTL were detected with CIM, four of which were in accordance with the major QTL detected with ICIM, that were qKRN2-1, qKRN4-2, qKRN8-2, and qKRN9-1. Cumulatively, the five major QTL explained 51.5% (BJ) and 54.0% (HN) of the phenotypic variance in the two environments with the GLM model, respectively. Correlation analysis showed that, in the two environments, correlations between the estimated values of phenotypic variance and observed values in F2:3 families were highly significant. In addition, two pairs of QTL located on three chromosomes (Chr. 2, Chr. 4 and Chr. 9) represented epistasis, explaining only a small part of the phenotypic variance, which were 2.90% and 1.80%, respectively. 【Conclusion】 Four-rowed waxy corn possessed a number of alleles with KRN-reducing effect and it could be a good resource in genetic analysis of maize KRN. The five QTL located in bin2.04, bin4.09, bin5.04, bin8.05 and bin9.03 could be considered as the major candidates for fine mapping and cloning in the future.

Key words: Zea mays L. , Four-rowed waxy corn , kernel row number (KRN) , quantitative trait loci (QTL) , genetic dissection