【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...【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F_1植株表型,对F_2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F_2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F_2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137kb,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_Os06g14620是WLP6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WLP6与St1等位,但突变位点不同,且表型也有差异。展开更多
Semi-dwarfing improves the lodging resistance and yield of rice,and the vast majority of modern rice varieties harbor the sd1 allele to decrease plant height,resulting in reduced genetic diversity and negative agronom...Semi-dwarfing improves the lodging resistance and yield of rice,and the vast majority of modern rice varieties harbor the sd1 allele to decrease plant height,resulting in reduced genetic diversity and negative agronomic traits.Thus,exploring alternative sources of dwarfism is imperative for rice breeding.Here,we identified a novel RGA1 allele,d1-w,from a local indica variety Xiaolixiang(XLX)using a map-based cloning approach.Compared with other rice varieties,RGA1 in XLX contained a unique single nucleotide polymorphism that resulted in an additional transcript and reduced functional RGA1 transcript level.The RGA1 from Nipponbare was introduced into XLX to estimate the value of d1-w in rice breeding.Compared with transgenic XLX plants(XLX^(D1)),XLX exhibited reduced plant height,increased stem strength,lower reactive oxygen species accumulation,delayed senescence,stronger photosynthesis,higher grain yield and quality(including external,milling and nutritional qualities),and enhanced resistance to drought and Rhizoctonia solani.Therefore,we proposed that the d1-w allele has potential as an excellent dwarfism resource for rice breeding.展开更多
文摘【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F_1植株表型,对F_2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F_2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F_2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137kb,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_Os06g14620是WLP6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WLP6与St1等位,但突变位点不同,且表型也有差异。
基金supported by grants from the National Natural Science Foundation of China (Grant Nos. 31960403 and 31501286)Jiangxi Natural Science Foundation-Outstanding Youth Science Fund Project,China (Grant No. 20212ACB215003)
文摘Semi-dwarfing improves the lodging resistance and yield of rice,and the vast majority of modern rice varieties harbor the sd1 allele to decrease plant height,resulting in reduced genetic diversity and negative agronomic traits.Thus,exploring alternative sources of dwarfism is imperative for rice breeding.Here,we identified a novel RGA1 allele,d1-w,from a local indica variety Xiaolixiang(XLX)using a map-based cloning approach.Compared with other rice varieties,RGA1 in XLX contained a unique single nucleotide polymorphism that resulted in an additional transcript and reduced functional RGA1 transcript level.The RGA1 from Nipponbare was introduced into XLX to estimate the value of d1-w in rice breeding.Compared with transgenic XLX plants(XLX^(D1)),XLX exhibited reduced plant height,increased stem strength,lower reactive oxygen species accumulation,delayed senescence,stronger photosynthesis,higher grain yield and quality(including external,milling and nutritional qualities),and enhanced resistance to drought and Rhizoctonia solani.Therefore,we proposed that the d1-w allele has potential as an excellent dwarfism resource for rice breeding.
