中国农业科学 ›› 2019, Vol. 52 ›› Issue (10): 1667-1677.doi: 10.3864/j.issn.0578-1752.2019.10.001

• 作物遗传育种·种质资源·分子遗传学 • 上一篇    下一篇

甘蓝型油菜半矮秆突变体dw-1的遗传分析与激素响应特性

宋稀1,蒲定福2,田露申1,余青青1,杨玉恒1,代兵兵1,赵昌斌1,黄成云1,邓武明1()   

  1. 1 南充市农业科学院,四川南充 637000
    2 四川绵邦农业科技有限公司,四川绵阳 621000
  • 收稿日期:2019-01-21 接受日期:2019-03-11 出版日期:2019-05-16 发布日期:2019-05-23
  • 通讯作者: 邓武明
  • 作者简介:宋稀,E-mail:xixi420.haha@163.com。
  • 基金资助:
    国家重点研发计划(2018YFD0100504);现代农业产业技术体系建设专项资金(CARS-12);四川省重大科技专项(2018NZDZX0003);四川省“十三五”农作物及畜禽育种攻关(2016NYZ0031)

Genetic Analysis and Characterization of Hormone Response of Semi-Dwarf Mutant dw-1 in Brasscia napus L.

SONG Xi1,PU DingFu2,TIAN LuShen1,YU QingQing1,YANG YuHeng1,Dai BingBing1,ZHAO ChangBin1,HUANG ChengYun1,DENG WuMing1()   

  1. 1 Nanchong Academy of Agricultural Sciences, Nanchong 637000, Sichuan
    2 Sichuan Mianbang Agricultural Science and Technology Co., Ltd, Mianyang 621000, Sichuan
  • Received:2019-01-21 Accepted:2019-03-11 Online:2019-05-16 Published:2019-05-23
  • Contact: WuMing DENG

摘要:

【目的】株高是影响油菜抗倒性、丰产性和全程机械化进程的关键性状,油菜矮秆、半矮秆资源的发掘与研究,是实现株高遗传改良的关键。目前油菜优异矮源缺乏,通过对获得的甘蓝型自然矮化突变体进行表型鉴定、遗传分析及激素相关形态学、生理学分析,旨在综合评估其利用潜能,为其在油菜矮化育种中的应用提供理论指导并为后续基因定位、克隆奠定基础。【方法】将甘蓝型油菜品系141492自交6代后发现的半矮秆突变体经游离小孢子培养获得DH系群体,选取1个半矮DH系,暂命名dw-1,其平均株高约95 cm,变幅83—105 cm。对dw-1农艺性状、经济性状、抗病性等进行表型鉴定,并以dw-1与野生型高秆为亲本构建6世代遗传群体,应用主基因+多基因混合遗传模型对株高进行遗传分析。通过光暗处理(16 h光照/8 h黑暗、24 h黑暗)形态学观察、下胚轴与茎秆赤霉素敏感性测验,鉴定突变体突变类型。【结果】与野生型相比,dw-1千粒重无明显变化,菌核病病指、二次分枝数、单株角果数显著或极显著增加,主序有效长、一次分枝数、株高、分枝部位高度、重心高度、主序角果数、每角粒数、单株产量显著或极显著降低,全生育期极显著缩短。遗传分析表明,dw-1株高的遗传受1对加性-显性主基因+加性-显性-上位性多基因控制(D-0模型),主基因加性效应-47.5,显性度0.2;B1、B2、F2主基因遗传率分别为76.0%、84.0%、85.0%,多基因遗传率分别为4.1%、5.6%、6.7%。光照与黑暗条件下,dw-1形态建成正常且下胚轴长度均极显著低于野生型。外施低浓度赤霉素对下胚轴与茎秆伸长作用不明显,高浓度处理有显著促进作用,但均不能恢复至野生型表型。【结论】dw-1田间综合性状优良,矮生性状以1对加性-显性主基因遗传为主,主基因又以加性效应为主,常规杂交育种早代选择有效。dw-1矮化机制与油菜素内酯途径无关,为赤霉素敏感性减弱应答类型。

关键词: 甘蓝型油菜, 矮化突变体, 遗传分析, 油菜素内酯, 赤霉素

Abstract:

【Objective】 Plant height has an great effect on lodging resistant, productivity and mechanical operation in rapeseed. Identification and research of dwarf and semi-dwarf germplasm in rapeseed will facilitate genetic improvement of plant height. At present, excellent dwarf germplasm in rapeseed is seriously deficient. In this study, we obtained a semi-dwarf natural mutant in B. napus and it was evaluated by phenotypic identification, genetic analysis and morphological and physiological analysis correlated to plant hormone. This work provide a theoretical basis for dwarf breeding and will contribute to further gene mapping and cloning.【Method】 A semi-dwarf mutant discovered from rapeseed line 141492 after six generations of self-crossing was used to produce DH population by isolated microspores culture, from which we choose one named dw-1 with the average plant height of 95 cm (83-105 cm) to identify its performance on agronomic traits, economic traits and disease resistance. Joint segregation analysis of six generations derived from a cross between dw-1 and wild type was carried out to reveal the inheritance of plant height based on major gene plus polygene mixed model. Morphology analysis of light and dark treatment (16 hL/8 hD, 24 hD) and exogenous gibberellins sensibility test of hypocotyls and stems were performed to classify the mutant. 【Result】 Compared with wild type, 1000-seed weight did not change while disease index of sclerotinia stem rot, number of secondary braches and number of siliques per plant increased significantly or extremely significantly in dw-1. Length of main inflorescence, number of primary branches, plant height, branch height, height of gravity center, number of siliques on main inflorescence, seeds per silique and yield per plant decreased significantly or extremely significantly and growth duration was shortened remarkably. Genetic analysis indicated that dw-1 was controlled by a pair of major gene with additive-dominant effects plus polygene with additive-dominant-epistasis effects (D-0 model). Additive effect and degree of dominance of major gene were -47.5 and 0.2, respectively. The heritability of major gene in B1, B2, F2 population were 76.0%, 84.0% and 85.0%, respectively, and those of polygene were 4.1%, 5.6% and 6.7%, respectively. Morphogenesis of dw-1 was normal and the length of hypocotyl of dw-1 was decreased significantly compared with the wild type regardless of light or dark condition (P < 0.01). Exogenous gibberellic acid 3 (GA3) with lower concentration had no obvious effect on elongation of hypocotyls and stems in dw-1 while they could be partially rescued in higher concentration but not to the wild type phenotype. 【Conclusion】 Mutant dw-1 with good comprehensive performance was mainly controlled by one pair of additive-dominant major gene dominated by additive effect. Selection of plant height can be carried out in earlier generation of conventional hybridization breeding. dw-1 was unrelated to brassinosteroid (BR) pathway and showed a reduced response to GA3.

Key words: Brassica napus L., dwarf mutant, genetic analysis, brassinosteroids, gibberellic acid