摘要
矮秆已被广泛用于改良作物的抗倒伏性状,培育理想株型,从而提高作物产量。玉米矮秆突变体K123d由自交系K123自然突变产生。本研究比较该突变体与野生型主要农艺性状差异及其对赤霉素的敏感性;用K123d与株高不同的3个自交系分别构建F1、BC和F2群体,分析矮秆性状的遗传模式;以K169/K123d-F2为定位群体,采用集团分离分析法(BSA),运用SSR标记定位矮秆基因d123;参照br-2序列信息分段设计特异引物,同源克隆d123。结果表明,与野生型相比K123d株高降低35.59%,穗位高降低、节间缩短、叶片较直立,但结实率差,对赤霉素敏感;在F2群体和BC1群体中,正常植株与矮秆植株分离比例分别符合3∶1和1∶1,说明矮秆性状受1对隐性基因控制;其矮秆基因d123定位于第一条染色体上SSR标记umc1278和bnlg1564之间,遗传距离分别为12.8 c M和7.3 c M;同源克隆显示d123与br-2存在12个碱基替换,其中第4个外显子编码的一个谷氨酸被替换为赖氨酸。由此可见,矮秆突变体K123d为br-2的一个突变类型,对矮化育种具有进一步研究利用价值。
Dwarf has widely been applied to improve the lodging resistance and to breed the ideal plant type in crops,hence increase the crop yield. A maize dwarf mutant K123d was derived from the inbred line K123 via spontaneous mutation. The objective of this study was to compare the differences of main agronomic traits and sensitivity to the gibberellins between the mutant and wild type. Genetic model of dwarf trait was analyzed by using F1 , BC and F2 populations derived from K123d and 3 inbred lines with different plant height. SSR primers were used to locate the dwarf gene d123 through bulked segregation analysis（BSA） by using K169/K123d-F2 as mapping populations. The specific primers designed based on sequence information of br-2 were used to clone homology gene d123. The results showed that compared with the wild type, K123d had shorter stalk by 35.59%, lower ear location, shorter internodes ,erecter leaves, poor fertility and sensitivity to gibberellins. In F2 and BC1 populations, the segregation ratios of normal to dwarf plants fitted 3： 1 and 1 ： 1 respectively,which demonstrated that the dwarf trait was controlled be different from br-2 by 12 bases varied, and the replacement of glutamate by lysine at the fourth exon. Our results demonstrated that dwarf mutant K123d was a br-2 variable type and it had further research and application value.
作者
徐敏
石海春
余学杰
谭义川
柯永川
赵长云
柯永培
XU Min SHI Hai-chun YU Xue-jie TAN Yi-chuan KE Yong-chuan ZHAO Chang-yun KE Yong-pei(College of Agronomy, Sichuan Agricultural University, Chengdu 611130 Sichuan Nongda Zhenghong Bio Co. ,Ltd Chengdu 610213 Leshan Academy of Agricultural Sciences, Leshan 614000)
出处
《植物遗传资源学报》
CAS
CSCD
北大核心
2017年第1期155-163,共9页
Journal of Plant Genetic Resources
基金
四川省科技支撑计划项目(2011FZ0119)
四川省战略性新兴产业发展专项资金项目(SC2013510122023)
四川省"十二五"农作物育种攻关项目(2011-3-11)
关键词
玉米
矮秆
基因突变
遗传分析
SSR标记
基因定位
同源克隆
maize
dwarf
gene mutation
genetic analysis
SSR marker
genetic mapping
homologybased cloning
