Genetic Analysis of a Biomass Mutant in Oryza sativa

[Objective] The study aimed to reveal the genetic model of a biomass mutant in Oryza sativa. [Method] In the process of screening and identification of Bar-transgenic rice,a biomass mutant was found in 10 lines of T1 progenies. The mutant was investigated for genetic analysis and agronomic traits by herbicide spraying and PCR amplification. [Result] The segregation ratio is consistent with mendelian law(3∶1). The mutant assumed not only higher plant height,wider straw and earlier florescence,but also more tillers,bigger spikes and resultantly higher biomass. PCR detections indicated that no co-segregation was observed between mutant traits and target gene(Bar) in the T-DNA inserted,proving that the mutant is not caused by the insertion of T-DNA containing target gene (Bar). [Conclusion] Our study may avail to understand the cloning of mutant gene and the mechanism of the mutant gene on biomass.     

一个水稻生物产量突变体的遗传分析(英文)

[Objective] The study aimed to reveal the genetic model of a biomass mutant in Oryza sativa. [Method] In the process of screening and identification of Bar-transgenic rice,a biomass mutant was found in 10 lines of T1 progenies. The mutant was investigated for genetic analysis and agronomic traits by herbicide spraying and PCR amplification. [Result] The segregation ratio is consistent with mendelian law(3∶1). The mutant assumed not only higher plant height,wider straw and earlier florescence,but also more tillers,bigger spikes and resultantly higher biomass. PCR detections indicated that no co-segregation was observed between mutant traits and target gene(Bar) in the T-DNA inserted,proving that the mutant is not caused by the insertion of T-DNA containing target gene (Bar). [Conclusion] Our study may avail to understand the cloning of mutant gene and the mechanism of the mutant gene on biomass.     

三个水稻联乙烯还原酶基因突变体的比较研究

 【Objective】 The present study was aimed at investigating the differences of mutant phenotypes resulting from different mutations in base sequence of rice divinyl reductase gene OsDVR (Os03g22780), and evaluating application potential of this gene in rice breeding as a leaf color marker gene. 【Method】The yellow-green leaf mutants isolated from Indica rice variety G46B and japonica rice variety Nipponbare via ethyl methanesulfonate mutagenesis were detected using high-performance liquid chromatography (HPLC) to screen the mutants accumulating divinyl chlorophyll. Then genetic analysis, gene mapping and allelism test of the target mutants were performed. Subsequently, DNA sequencing of OsDVR gene in these mutants and alignment of the deduced amino acid sequences of homologous DVR proteins were conducted, and leaf photosynthetic pigments, plant phenotypes and main agronomic traits of the mutants were investigated. 【Result】590ys and 525ys, two novel mutants accumulating divinyl chlorophyll, were obtained by screening 53 yellow-green leaf mutants isolated from ethyl methanesulfonate mutagenesis. Their mutant phenotypes were all controlled by a pair of recessive nuclear gene and moreover, the mutant genes were all mapped on the chromosomal region harbouring the 824ys mutant gene reported. Furthermore, allelism test confirmed that the mutant genes of 590ys and 525ys were allelic to that of 824ys. So 590ys, 525ys and 824ys mutants were all OsDVR mutants. However, mutational sites of OsDVR mutant gene and their encoded protein product in the three mutants were different, which resulted in extremely significant differences of chlorophyll contents and compositions, plant phenotypes, main agronomic traits and yields per plant among the three mutants. Among them, 525ys mutant had slight yellow leaves, and its growth and development, main agronomic traits and yield per plant were affected relatively less, indicating that 525ys mutant gene can basically meet the requirements as a leaf color marker gene introduced into rice male sterile lines. 【Conclusion】Different mutations in base sequence of OsDVR gene could result in extremely significant differences of mutant phenotype and yield per plant. The OsDVR mutant gene could be applicable in hybrid rice breeding as a leaf color marker gene.     

Identification of a Long Rice Spikelet Mutant

A spontaneously occurring rice (Oryza sativa L.) mutant, characterized by homeotic conversion in glumes and stamens, was found in the progeny of a cross. The mutant showed long glumes and glumaceous lodicules and morphological transformation of stamens into pistils. Mutant florets consisted of 1 to 3 completely developed pistils, some pistilloid stamens with filaments, but tipped by bulged tissue and 0 to 3 stigmas. It seems that the mutant phenotype of the homeotic conversions in glumes and stamens is similar to that of the B loss-of-function mutants in Arabidopsis and Antirrhinum. The mutant is controlled by a single recessive gene as a segregation ratio of 3:1 (wild type to mutant plants) was observed in the F2 generation.     

Blast-Resistance Inheritance of Space-Induced Rice Lines and Their Genomic Polymorphism by Microsatellite Markers

To understand the resistance inheritance basis of space-induced rice lines to blast, and to probe mutants＇ genomic DNA polymorphism compared with ground control by microsatellite markers, three space-induced lines were crossed with a highly susceptible variety LTH, and their F1 and F2 populations were inoculated by two representative blast isolates with broad pathogenicity to analyze their resistance inheritance basis. Meanwhile three mutant lines and the ground control were analyzed by 225 rice SSR （simple sequence repeat） primer pairs selected throughout the 12 chromosomes of whole rice genome, to scan the mutagenesis in genome of the mutant lines. The results indicated the blast-resistant genes harbored in these mutant lines were dominant. It was demonstrated that the resistance of mutant H1 to isolate GD0193 and GD3286 was controlled by a single gene, respectively; while mutants H2 and H3 were controlled by two pairs of major genes against isolate GD3286 and H2 showed complicated genetic mechanism to isolate GD0193. H3＇s resistance to isolate GD0193 was verified to be controlled by a single gene. According to the results of SSR analysis, three mutant lines showed different mutant rates as compared with the ground control, and the mutant rates also varied. Resistance genes can be induced from rice by space mutation, and different genomic variations were detected in blast-resistant lines.     

Detection of QTLs for Important Agronomic Traits and Analysis of Their Stabilities Using SSSLs in Rice

Single segment substitution lines （SSSLs） each with a single chromosome segment from a donor under the same genetic background as the recipient were developed in rice by advanced backcrossing and molecular marker-assisted selection. Using the SSSLs, the QTLs for the important agronomic traits in rice would be detected under different environmental conditions. Detection of the QTLs controlling 22 important traits in rice was done with 32 SSSLs by the randomized block design in 2-4 cropping seasons. 59 QTLs were detected and distributed on chromosomes 1, 2, 3, 4, 6, 7, 8, 10, and 11, of which 18 QTLs were detected more than twice. Only 30.5% of the QTLs were detected repeatedly in different cropping seasons. Most of the QTLs of important agronomic traits were of little additive effects and instability. The QTLs controlling the traits, such as grain weight, grain length, ratio of grain length to width, and heading date were relatively stable. The stable QTLs usually had larger additive effects and were less affected by environment. The QTLs for the important agronomic traits were detected using the SSSLs in rice with high resolution under different environmental conditions. The instability of the QTLs may be the basis of the variation of rice plants during growth and development. It would be the genetic basis for improving yield and quality in rice cultivars by farming methods.     

Comparing Genetic Characteristics of Retrotransposon TOS17 During Different Tissue Culture Processes in the Rice Cultivars Nipponbare and Shishoubaimao

As a retrotransposon, TOS17 was a useful tool for rice genetic and functional genomic research. To ascertain the feasibility of constructing a TOS17 insertion mutation library in the rice cultivar Shishoubaimao, the genetic and expression characteristics of TOS17 were analyzed. We made solid and suspension tissue cultures and confirmed the copy numbers of TOS17 at different time points in both tissue culture processes by real-time quantitative PCR （RT-qPCR）. Three primary copies of TOS17 were detected in naturally grown Shishoubaimao. TOS17 was activated by tissue culture, and the copy numbers of TOSI7 increased along with a prolonged tissue culture time in both the Nipponbare and the Shishoubaimao cultivars. Therefore, Shishoubaimao is a potential candidate for constructing a TOS17 insertion mutant library. Compared with Nipponbare, TOS17 was more active in Shishoubaimao during tissue culture. Higher copy numbers of TOS17 were obtained with the suspension tissue culture process than with the solid tissue culture process over the same time courses. We concluded that 3-4 months of suspension tissue culture time is suitable for constructing a TOS17 insertion mutant library in Shishoubaimao.     

云南地方香稻与非香稻遗传多样性比较(英文)

[Objective] The genetic diversity of the local cultivated aromatic rice and non-aromatic rice in Yunnan Province were compared to provide further genetic resources for breeding practice.[Method] Genetic diversity of 10 aromatic rice and 45 non-aromatic rice were analyzed by 64 SSR primers covered on 12 rice chromosomes. [Result] Per locus 5.44 and 7.98 alleles in average were detected, ranging from 2 to 12 and from 2 to 17 in aromatic and non-aromatic rice , respectively. Average genetic multiplicity index(Hs) was 0.46 and 0.67 respectively. The average polymorphism information content (PIC) was 0.43 and 0.58 in aromatic and non-aromatic rice respectively.[Conclusion] The results indicated that genetic diversity was higher in non-aromatic rice than in aromatic rice.     

Analysis of Sugar Components of Fermented Rice Wine by Ion Chromatography

[Objective] The aim was to analyze sugar components in fermented rice wine by ion chromatography. [Method] The optimal condition for chromatography system of sugar analysis was selected by measuring sugars in fermented rice wine with ion chromatography and pulsed amperometric detection. [Result] The optimal measurement conditions were as follows： Leacheate （Leachate）, consisting of NaOH and CH3COONa, was eluted by gradient concentrations, with column temperature at 35 ℃ and flow rate at 0.4 ml/min. In the condition, sugars in rice wine were ana- lyzed and the results showed that the method is featured by low detection limit, good repetition and high recovery rate. [Conclusion] The research establishes and determines the approaches and optimum conditions for sugar analysis in rice wine by ion chromatography and pulsed amperometric detection, providing references for advancement of research on quality improvement of fermented rice wine.     

T-DNA插入产生的水稻小粒突变体遗传分析

[目的]研究水稻粒形突变体的遗传特性及其在水稻遗传改良中的作用。[方法]筛选水稻T-DNA插入纯合体,鉴定表型变异,通过表型突变的遗传分析及其与T-DNA插入共分离的检测,研究水稻表型突变的遗传特性。[结果]观察到1个粒形突变体T56。主要表现为粒长变短、粒宽变窄及千粒重降低;对该突变体进行遗传分析,分离群体出现野生型和突变体2种类型,其分离比符合3∶1,表明该突变体表型受1对隐性基因控制。突变体及其后代分离群体的Basta抗性检测和PCR分子检测结果表明,该突变体由T-DNA插入所引起,突变性状与T-DNA共分离。[结论]该材料可用于插入座位的基因克隆和水稻遗传改良的种质资源。     

批量筛选水稻T-DNA插入突变体库获得生殖发育相关突变体

针对花器官形态和种子发育突变表型对大型水稻T-DNA插入突变体库进行筛选,获得了大量突变体信息及材料,在9 760个突变体家系中筛选得到177个花器官形态和数量异常的突变家系,突变频率为1.81%;对9 760个家系中的3 432个家系筛选得到179个种子发育缺陷的突变家系,突变频率为5.22%。对所获得的270个突变家系进行了T-DNA插入的阳性检测,阳性率为64.8%。利用公共数据库RMD(Rice MutantDatabase,RMD)给定的侧翼序列,鉴定了其中1个结实率较低的突变体家系,表明其突变表型和T-DNA插入共分离,为深入研究该基因的功能提供了重要的遗传材料。     

稻瘟菌若干T-DNA插入突变体初步分析

为揭示稻瘟菌致病分子机制,创建了该菌T-DNA插入突变体库．部分突变体经表型分析,获得3个生长发育及致病性同时发生变异,5个生长发育正常但致病性变异及2个生长发育变异但致病性正常的突变体；以TAIL-PCR方法获得了这些突变体T-DNA插入位点及其边界序列,并用生物信息方法对被T-DNA标签的基因进行了分析,为进一步研究这些基因的功能提供了重要信息．     

水稻穗形态建成基因PMM1的遗传分析与初步定位

在水稻粳稻品种中花11T-DNA插入突变体库中鉴定了3个穗形态突变体,它们均表现为植株半矮、叶夹角变小、一次枝梗轮生、复粒、粒长变短、粒宽变宽等突变表型。基因双突变杂交F1表型考查证明这3个突变体为等位突变体,T-DNA标签共分离检测表明这3个突变体的表型与T-DNA插入无关。通过与籼稻品种珍汕97配置3个杂交组合,由经典的孟德尔遗传分离比显示,突变性状受1对隐性基因(panicle morphological mutant 1,PMM1)控制。采用基因图位克隆的方法,已将基因PMM1定位在第4染色体长臂上的RM3866-1和X4(InDel)标记之间,其两侧物理图距为147kb左右。     

一个水稻生物产量突变体的遗传分析

突变体是研究基因功能的重要材料。除自然突变和物理、化学方法外，T—DNA插入诱变、转座子插入诱变等分子生物学手段也得到广泛的应用。而水稻全基因组测序的完成和水稻分子标记技术发展，使得通过图位克隆法从非插入突变的水稻突变体获得相关基因变得相对容易，目前，在水稻上通过图位克隆已克隆到一些重要的基因。该研究在转Bar基因水稻后代T1代群体中发展了一个高生物产量突变体，并对该突变体进行遗传分析，为该基因的克隆和功能分析提供参考。     

Genetic Analysis of a Biomass Mutant in Oryza sativa

[Objective] The study aimed to reveal the genetic model of a biomass mutant in Oryza sativa. [Method] ln the process of seresning and iden-tification of Bar-transgenic rice, a biomass mutant was found in 10 lines of TI progenies. The mutant was investigated for genetic analysis and agronomic traits by herbicide spraying and PCR amplification. [Result] The segregation ratio is consistent with mendelian law(3:1). The mutant assumed not only higher plant height, wider straw and earlier florescence, but also more tillers, bigger spikes and resuhantly higher biomass. PCR detections indicated that no co-segregation was observed between mutant traits and target gene(Bar) in the T-DNA inserted, proving that the mutant is not caused by the insertion of T-DNA containing target gene (Bar). [Conclusion] Our study may avail to understand the cloning of mutant gene and the mechanism of the mutant gene on biomass.     

一个水稻生物产量突变体的遗传分析

[目的]对1个水稻生物产量突变体进行遗传分析。[方法]对转Bar基因水稻后代的筛选和鉴定的过程中,在T1代群体10个株系中发现1个生物产量突变株系;采用除草剂Basta喷洒及PCR扩增等方法对该株系进行遗传分析并进行农艺性状考察。[结果]该基因突变除了使株型增高外,径秆也较粗,开花较早,分蘖多,穗大,生物产量高。该株系分离比率为3∶1,符合孟德尔遗传分离规律。PCR分子检测证实,突变性状与T-DNA插入的目的基因(Bar)没有共分离,表明突变体不是由目的基因的T-DNA插入所引起的。[结论]该研究有助于克隆该突变体诱发基因及理解其对生物产量影响机制。     

一个水稻卷叶突变体zw209的遗传分析与精细定位

叶片是植物光合作用的主要场所,优良的叶片形态有利于塑造理想株型,提高光合效率。为了研究叶片形态建成的分子机制,从水稻T-DNA突变体库中筛选到1个叶片极度卷曲的突变体zw209,突变体有2个显著特征:1突变体泡状细胞数量和面积均变小;2突变体的叶绿素含量较高,具有较高的光合效率。遗传分析表明,zw209的突变性状由一对隐性核基因控制。通过图位克隆,将基因(ZW209)精细定位到9号染色体长臂上,位于In Del136和In Del140之间的92.3 kb区域内。在这个区域内,尚未见报告已克隆的卷叶基因,很可能是一个新的基因位点。上述结果明确了突变体的表型特征及遗传规律,为克隆ZW209基因和揭示其作用机理奠定基础。     

一个水稻T-DNA插入类病斑突变体的初步研究

从T-DNA插入突变体中筛选到一个类病斑突变体AZT91,主要表现为生长缓慢、植株矮小、叶片出现条状褐斑,最后死亡。对突变体及其后代分离群体进行潮霉素抗性检测,证明该突变体是由T-DNA插入突变引起的,突变性状与T-DNA共分离。PCR和TAIL-PCR分析进一步证明了上述的观点。利用TAIL-PCR扩增了左边界侧翼序列,通过分析,初步推测该突变体可能是由于T-DNA插入后激活了单加氧酶基因的过量表达,破坏正常代谢途径,导致突变体死亡。该材料可用于水稻代谢调控机理的研究。