Chinese Journal OF Rice Science ›› 2018, Vol. 32 ›› Issue (6): 538-548.DOI: 10.16819/j.1001-7216.2018.7144

• Orginal Article • Previous Articles     Next Articles

Identification and Gene Mapping of White Stripe Leaf and White Panicle Mutant wlp6 in Rice

Lingfeng LI#, Yuyi XIONG#, Linjuan OUYANG, Xiaosong PENG, Xiaorong CHEN, Xiaopeng HE, Junru FU, Jianmin BIAN, Lifang HU, Jie XU, Haohua HE, Xiaotang SUN*(), Changlan ZHU*()   

  1. Key Laboratory of Crop Physiology, Ecology and Genetics and Breeding of Ministry of Education, Jiangxi Agricultural University, Nanchang 330045, China
  • Received:2017-11-26 Revised:2017-12-29 Online:2018-11-27 Published:2018-11-10
  • Contact: Lingfeng LI, Yuyi XIONG, Xiaotang SUN, Changlan ZHU

水稻白条纹叶及白穗突变体wlp6的鉴定与基因定位

李玲锋#, 熊玉毅#, 欧阳林娟, 彭小松, 陈小荣, 贺晓鹏, 傅军如, 边建民, 胡丽芳, 徐杰, 贺浩华, 孙晓棠*(), 朱昌兰*()   

  1. 江西农业大学 作物生理生态与遗传育种教育部重点实验室, 南昌 330045
  • 通讯作者: 李玲锋,熊玉毅,孙晓棠,朱昌兰
  • 基金资助:
    国家自然科学基金资助项目(31560507);江西省“5511”优势科技创新团队资助项目(20165BCB19005);江西省教育厅项目(GJJ150409)

Abstract:

【Objective】Leaf color mutants are important materials for studying the regulation of photosynthesis, chlorophyll biosynthesis and genetic development in rice. The discovery of leaf color mutants is an important genetic basis for functional genomics research in rice. 【Method】 A mutant of white stripe leaf and white panicle was found in Changhui 121, which could be inherited stably to successive generations, and temporarily termed wlp6 (white striped leaf and panicle 6). wlp6 and wild-type seeds were seeded in the early, middle and late seasons in Nanchang, Jiangxi Province and the agronomic traits of the middle and late rice were investigated. Chlorophyll contents in leaf and glume at the 3-leaf stage, tillering stage and heading stage were tested. The development of mesophyll cells at the heading stage was observed with a electron microscopy. Temperature and light sensitive experiments were carried out in an illumination incubator. The phenotype of reciprocal F1 between wlp6 and Changhui 121, 02428 was observed and chi-square test was conducted on F2 segregating population to analyze the genetic pattern of the mutant. The F2 population derived from wlp6/02428 was used as material, and the mapping was carried out by the BSA method. 【Result】 From 1-leaf stage to mature stage, all leaves of wlp6 showed white stripes. At the heading stage, glumes and branches were albino, and the panicle turned green under high temperature. The plant height, number of effective panicles and number of grains per panicle of the mutant were significantly lower than those of its wild type in the two seasons, and the seed-setting rate and 1000-grain weight of wlp6 in late season were also significantly lower. The leaf chlorophyll contents of wlp6 were significantly lower than those of the wild type at all growth stages. The husk chlorophyll contents of wlp6 were significantly lower than those of the wild type in early and late season. In wlp6, the number of chloroplasts decreased, the volume became smaller, and there was no obvious lamellar structure. Leaf chlorophyll contents increased with the temperature and sunshine duration increase. Genetic analysis showed that the trait was controlled by recessive nuclear genes. WLP6 was located in the interval InDel markers R-7-R-8(physical distance 137 kb), on the short arm of chromosome 6. In this interval, 21 candidate genes were predicted. Through the analysis of candidate genes and sequencing, we found that LOC_Os06g14620 encodes a small chain of RNA reductase, 142nd and 158th base of the coding region carried a substitution from T to C, and the base A was inserted at the 288th position. The insertion of the base leads to termination of the gene translation. Therefore, it is speculated that LOC_Os06g14620 is the candidate gene for WLP6.【Conclusion】LOC_Os06g14620 is the candidate gene of the cloned white stripe gene St1. WLP6 is the allele of St1, with different mutation sites and phenotypes.

Key words: rice, white stripe and white panicle, chlorophyll, temperature and light sensitive, gene mapping

摘要:

目的 叶色突变体是研究水稻光合作用,叶绿素生物合成和遗传发育调控机理的重要材料。发掘水稻叶色突变体,是水稻功能基因组学研究的重要遗传基础。方法 在昌恢121中发现了一份白条纹叶及抽穗期白穗突变体,经过连续多代自交能稳定遗传,暂命名为wlp6(white striped leaf and white panicle 6)。在南昌分早、中和晚3季播种wlp6与野生型种子,考查了中稻与晚稻的部分农艺性状;测定3叶期、分蘖期、抽穗期叶片及颖壳的叶绿素含量;通过电镜观察抽穗期叶肉细胞发育情况。在光照培养箱中进行温光敏感实验;将wlp6与昌恢121及02428正反交,观察F1植株表型,对F2分离群体进行卡方测验,分析突变体遗传规律;以wlp6/02428衍生的F2群体为材料,利用BSA法进行基因定位。结果 wlp6自第1片叶到成熟,叶片均呈白条纹,抽穗期颖壳及枝梗失绿,高温天气穗转绿。突变体株高、有效穗数和每穗粒数在早稻季和中稻季均显著低于野生型,晚稻季wlp6的结实率和千粒重也显著低降低。叶绿素含量测定表明,wlp6叶片叶绿素含量在不同生育期及不同季均显著低于野生型,早稻和晚稻季种植的wlp6颖壳叶绿素含量也比野生型低。电镜观察抽穗期的叶肉细胞发现,wlp6叶绿体数目减少,体积变小,没有分化出明显的片层结构。温光敏感实验表明,突变体对光照强弱钝感,叶色受温度和日照长短影响,随着温度升高和日照时间变长突变体叶绿素含量有上升趋势。遗传分析表明,该性状受隐性核基因控制,利用wlp6/02428得到的616个F2单株将WLP6定位于第6染色体短臂InDel标记R-7与R-8间,物理距离137 kb,此区间预测了21个候选基因。经候选基因分析及测序发现,其中LOC_Os06g14620编码一个核糖核酸还原酶小亚基,编码区第142和158位碱基由T替换为C,第288位插入了碱基A,碱基的插入导致翻译提前终止,因此推测LOC_Os06g14620WLP6的候选基因。结论 LOC_Os06g14620是已经克隆的白条纹叶基因St1的候选基因,推测WLP6St1等位,但突变位点不同,且表型也有差异。

关键词: 水稻, 白条纹叶及白穗, 叶绿素, 温光敏感, 基因定位

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