遗传 ›› 2018, Vol. 40 ›› Issue (5): 402-414.doi: 10.16288/j.yczz.17-401

• 研究报告 • 上一篇    下一篇

玉米CMS-C同质异核不育系育性恢复的遗传研究

赵卓凡1,黄玲1,2,刘永明1,张鹏1,魏桂1,曹墨菊1()   

  1. 1. 四川农业大学玉米研究所,教育部作物基因资源与遗传改良重点实验室,农业部西南玉米生物学及遗传育种重点实验室,成都 611130
    2. 四川省农业科学院经济作物育种栽培研究所,成都 610300
  • 收稿日期:2017-12-07 修回日期:2018-02-07 出版日期:2018-05-20 发布日期:2018-04-26
  • 通讯作者: 曹墨菊 E-mail:caomj@sicau.edu.cn
  • 作者简介:赵卓凡,硕士研究生,专业方向:玉米生物技术育种。E-mail: zhaozfqc@163.com
  • 基金资助:
    国家重点研发计划项目(2016YFD0101206);四川省科技厅支撑计划项目资助(2016NZ0106)

Genetics of fertility restoration in the isocytoplasm allonuclear C-group of cytoplasmic male sterility in maize

Zhuofan Zhao1,Ling Huang1,2,Yongming Liu1,Peng Zhang1,Gui Wei1,Moju Cao1()   

  1. 1. Key Laboratory of Crop Genetic Resource and Improvement of Ministry of Education, Key Laboratory of Biology and Genetic Improvement of Maize in Southwest Region of Ministry of Agriculture, Maize Research Institute, Sichuan Agricultural University, Chengdu 611130, China
    2. Industrial Crops Research Institute, Sichuan Academy of Agricultural Sciences, Chengdu 610300, China
  • Received:2017-12-07 Revised:2018-02-07 Online:2018-05-20 Published:2018-04-26
  • Contact: Cao Moju E-mail:caomj@sicau.edu.cn
  • Supported by:
    Supported by the National Key Research and Development Project of China(2016YFD0101206);the Science and Technology Department of Sichuan Province(2016NZ0106)

摘要:

玉米是最早利用细胞质雄性不育系生产杂交种的作物之一,C型细胞质雄性不育系(C-type cytoplasmic male sterile, CMS-C)在杂交种生产中具有重要的作用,育性恢复的稳定性直接影响其应用价值。然而,玉米CMS-C的育性恢复机理复杂,且至今仍不明确。为进一步探究玉米CMS-C育性恢复的影响因素,本研究以玉米CMS-C同质异核不育系C48-2、C黄早四和C478为母本,分别与测验系18白、自330、5022以及恢复系A619组配杂交获得F1。其中育性恢复F1通过自交获得F2,并以育性恢复F1为父本分别给育性保持F1授粉,组配双交群体,共获得4个F2群体,6个双交群体。同时以不育系C48-2、C黄早四和C478为母本,各自的保持系48-2、黄早四和478为父本杂交组配不完全双列杂交F1。将所有杂交组合的F1、F2以及双交组合群体分别在不同年份不同地点种植观察,通过植株田间育性调查并结合室内花粉镜检鉴定育性表现。结果表明:1) 同一测验系对玉米CMS-C同质异核不育系的恢保关系不同,暗示不育系的核背景参与调控育性恢复表现;2) 在不同年份不同地点对(C48-2×A619) F2群体进行种植观察,发现不同环境下F2群体可育株与不育株的分离比均符合15∶1,但在云南种植的可育株的育性级别主要为Ⅲ和Ⅳ级,而在四川种植的可育株的育性级别主要为Ⅴ级,表明环境对恢复系A619恢复后代的育性表现有影响;3) 通过恢保关系测定发现18白不能恢复C478,48-2也不能恢复C478,但双交群体[(C478×18白) F1S×(C48-2×18白) F1F]后代却出现了可育株与不育株的分离;同理,双交群体[(C48-2×自330) F1S×(C478×自330) F1F]的后代也出现了可育株与不育株的分离。因此,本文推测C48-2、C478核背景中存在微效恢复基因,这些微效基因与18白、自330中的微效恢复基因通过杂交聚合后能使C478、C48-2的育性恢复,暗示玉米CMS-C的育性恢复呈现一定的剂量效应。这些结果为进一步认识玉米CMS-C育性恢复的复杂性和多样性奠定了基础,为深入研究玉米CMS-C育性恢复机理以及加快CMS-C在不育化制种中的应用提供重要参考。

关键词: 玉米, CMS-C, 育性恢复, 双交群体

Abstract:

Maize is one of the first crops to produce hybrids using cytoplasmic male sterile lines. The C-type cytoplasmic male sterile (CMS-C) line is vital for hybrid seed production, and the fertility-restoration reaction along with its stability has a direct bearing on its applications. However, fertility restoration mechanism of CMS-C is complex and is still not clear so far. To further explore the factors affecting the fertility restoration of maize CMS, a series of test crosses were carried out by pollinating the isocytoplasm allonuclear CMS-C lines C48-2, Chuangzaosi and C478 with the test lines 18 bai, zi 330, 5022 and the restorer line A619, respectively. Four F2 populations and six double-cross combinations were obtained from the self-cross of fertility restored F1 and pollinating male-sterility-maintained F1 with the male-fertility-restored F1, respectively. Meanwhile, we developed the incomplete diallel-cross combinations using the isocytoplasm allonuclear male sterile lines as maternal parents and their respective maintainer lines 48-2, huangzaosi and 478 as paternal parents. All the F1, F2 and double-cross populations were planted at distinct locations in different years, and the fertility-restoration reaction was scored by field investigation and pollen staining with I2-IK. The results were as follows: 1) The same test line could restore the CMS-C line at a certain genetic background, but failed to restore the CMS-C line at the other genetic backgrounds, suggesting that the genetic background of CMS-C lines plays an important role in the fertility restoration. 2) The fertile-to-sterile segregation ratio of (C48-2×A619) F2 population planted in both Sichuan and Yunnan fited well to 15∶1 by the χ 2 test. However, the fertility level of individuals in Yunnan mainly belonged to the Ⅲ and Ⅳgrades, but which in Sichuan mainly belonged to the Ⅴ grade, indicating the environmental factors had effect on the fertility-restoration reaction of (C48-2×A619) F2. 3) In our study, 18 bai could not restore C478, and 48-2 could not restore C478, but the fertile and sterile segregated plants were unexpectedly found in their double-cross population [(C478×18 bai) F1S×(C48-2×18 bai) F1F]. The similar case was also observed in the double-cross population [(C48-2 × zi 330) F1S × (C478 × zi 330) F1F]. Therefore, we speculated that there are minor fertility restorer genes not only in the nuclear background of C48-2 and C478, but also in zi 330 and 18 bai, and when these minor genes were gathered by hybridization, they could restore the fertility of C478 and C48-2. This conforms to the restorer genes dose-effect for fertility restoration in the plant CMS system. These results not only contribute to our understanding of the complexity and diversity of CMS-C restoration mechanism, but also provide an important reference for the practical applications about maize CMS-C.

Key words: maize, CMS-C, fertility restoration, double-cross populations