Mechanism of immunization of rice seedlings

In saline paddy soil in the north of China, the technique of immunization of rice nursery (IRN) was applied in 1990‘s and succesfuully met the production needs. It had more advantages than paddy soil land nursery (PSLN).     

Development of Chinese near-isogenic lines of rice and their differentiating ability of pathogenic races of blast fun-gus

To use common differential varietiesin the world, a set of internationaldifferential varieties, including 6 in-dica and 2 japonica rice varieties,were set up in the midddle of 1960s;in 1976, a set of differential varietiescmposed of 9 japonica varieties withknown resistance gene were estab-lished; and later a set ofnear-isogenic lines (NILs), 4 lines     

Effect of desiccation on regeneration frequency of green plantlets and some biochemical properties of calli of wild rice

Wild rice is an important resource of useful genes to rice breeders. However, low regeneration frequency is an obstacle to use the valuable genes. We used desiccation to improve the regeneration frequency and studied the biochemical changes of calli of wild rice after desiccation,     

Levels of β-carotene and effects of processing on selected fruits and vegetables of the arid zone of India

Some locally available fruits and vegetables of the arid zone of Rajasthanwere analyzed for their -carotene content; the selected fruits and vegetables were: Dansra (Rhus myserensis), Kachri (Cucumis collosus), fruit Kachri (Cucumis collosus), Kair (Capparisdecidua) and Sanghri (Prosopis cineriria). The -carotene contents of the samples were estimated in fresh and various processed states (blanched, dried and roasted). The results showed the heat lability of -carotene. Among the samples, kair was found to be the richest source of -carotene. Variety, too, had an impact on the content of this fat soluble vitamin.     

Serological specificity of leaf streak pathogen of rice

The leaf streak of rice is one of the seedborne and quarantine bacterial disease in China. The rice seeds must be strictly inspected to prevent the disease from spreading. The serological test is a rapid and accurate method of identifying seedborne bacterial plant pathogens. But the specificity and thus reliability of any serological method depend first on the specificity of the antiserum. Therefore, a high specificity of antiserum is always required for and has become a key in detecting the leaf streak pathogen in rice seeds. The present study was conducted on the method of improving the specificity. Two group of antigen, the yellow and white proteins, were extracted from the cells of Xanthornonas oryzae pv. oryzicola by the methods of stepwise precipitation with ammonium sulfate and differential centrifugation. Antiserum A and B against the yellow and white proteins were each produced in white rabbit immunized with the proteins respectively. The tittle of the two antiserum were the same(1: 6400).     

AMMI analysis of interaction of genotype and environment in chalkiness of indica rice

Chalkiness is an unpleasant trait for rice con-sumer. which is known to be controlled geneti-cally and affected by environment during grainmaturing. We used the model of Additive MainEffects and Multiplieative Interaction (AMMI)for interpreting the result of genotype by env-iornment interaction (G×E) in the chalkinessof indica rice varieties.     

Influence of nitrogen on relative parasitic fitness of cultivar-race combinations of rice blast

Rice blast, caused by Magnaporthe grisea, is one of the most important rice diseases in China. Resistance breakdown often happened, especially in the field supplied with high nitrogen fertilizer. In the simulation study on race dynamics and cultivar-race interaction on population level, the influence of nitrogen on the relative parasitic fittness of cultivar-race combinations should be realized quantitative-ly.     

粳稻BT型细胞质雄性不育恢复基因功能标记的开发与应用

 为提高粳稻BT型细胞质雄性不育恢复基因的选择效率,在前人克隆的基础上,根据其恢复系与不育系在Rf1a位点574 bp的碱基插入/缺失,设计出功能标记InDel Rf1a。利用该标记对不同地区来源的72份籼、粳稻材料进行检测,结果表明所有的常规籼稻品种、恢复系及保持系在Rf1a位点并不存在缺失,其基因型为Rf1aRf1a。这些材料对粳稻BT型细胞质雄性不育系具有恢复育性的作用;而绝大多数常规粳稻品种（爱知106和伊粳12号除外）在该位点存在缺失,其基因型为rf1arf1a,它们对BT型细胞质雄性不育系具有保持不育的能力。同时,为进一步验证该标记对不同基因型的检测效果,利用其对粳稻恢复系、不育系、杂交组合以及863A/宁恢 8号 F2分离群体的DNA进行扩增,根据其电泳带型可准确区分出Rf1a位点的3种基因型。     

分子标记辅助选择改良C418对红莲型粳稻不育系的恢复力

【目的】高效选育红莲型(Honglian,HL)粳稻恢复系有助于HL型杂交粳稻育种,对促进三系杂交粳稻的发展具有重要的意义。【方法】Rf6是一个HL型恢复基因,来源于HL型籼稻强恢复系9311。前期研究中,在以9311为供体、日本晴为受体的一套染色体片段代换系中鉴定出携带Rf6的株系R1093。本研究利用R1093与BT型粳稻恢复系C418(携带Rf1)杂交,通过常规回交育种结合分子标记辅助选择技术,将Rf6导入C418中,进行Rf6与Rf1聚合育种;利用BT型、HL型六千辛A进行测交鉴定改良系的恢复力。【结果】共获得12个BC₃F₄株系和55个BC₄F₃株系,其中6个改良系的农艺性状已基本接近C418;测交鉴定结果表明聚合Rf6的改良系对HL型粳稻不育系的恢复度达到85%以上,可应用于水稻生产;对BT型粳稻不育系的恢复度提升效果不显著。【结论】聚合Rf6能有效改良BT型粳稻恢复系对HL型粳稻不育系恢复力,是选育HL型粳稻恢复系的一条重要途径。     

Development of Simple Functional Markers for Low Glutelin Content Gene 1 （Lgc1） in Rice （Oryza sativa）

Rice with low glutelin content is suitable as functional food for patients affected by kidney failure. Low glutelin-content gene Lgc1 in rice has a 3.5-kb deletion between two highly similar glutelin genes GluB4 and GluB5, which locates on the short arm of chromosome 2. To improve the selection efficiency in low glutelin-content rice breeding, two molecular markers designated as InDel-Lgc1-1 and InDel-Lgc1-2 were developed to detect the low glutelin-content gene Lgc1. A double PCR detection indicated that combined use of the two markers could easily distinguish the genotypes of Lgc1 from different rice varieties. Therefore, as a simple and low-cost technique, the molecular marker could be widely used to identify different varieties with Lgc1 gene and applied in marker-assisted selection of low glutelin-content rice.     

红莲型不育细胞质在杂交粳稻育种中的应用

为了探讨红莲型不育细胞质应用于杂交粳稻育种的可能性,利用包台(BT)型、红莲(HL)型、茶野(CL)型、野败(WA)型等4种细胞质的同核异质不育系六千辛A与181个粳稻亲本测交,根据测交F1的小穗育性,筛选HL型粳稻恢复系。在此基础上,对筛选出的HL型粳稻恢复系与更多HL型不育系复测,并进行不同细胞质杂交粳稻的比对试验。研究结果表明:1)HL型和CL型不育系的恢、保关系十分一致,测交F1小穗育性间的相关性达极显著水平。2)HL型和CL型粳稻不育系的可恢性虽不如BT型不育系,但明显优于WA型粳稻不育系;以测交F1小穗育性达到85%以上作为选择标准,从BT型恢复系和广亲和恢复系中筛选出25个HL型(CL型)粳稻恢复系。3)不育系的核背景对杂种育性有影响,HL型六千辛A可恢性最好,其次为HL型陵香A,HL型珍5A可恢性最差。4)与BT型不育系配制的杂种相比,HL型和CL型不育系配制的杂种育性稳定性相对较差。5)HL型不育系配制的杂种与BT型、WA型不育系配制的杂种在播种至抽穗历期、株高、产量及品质性状上均无明显差异;HL型不育系配制的杂交粳稻结实率正常,与BT型不育系配制的杂种无明显差异,明显高于WA型不育系配制的杂种。说明HL型不育细胞质应用于杂交粳稻育种是可行的。     

BT型粳稻不育系8006A的选育与应用

8006A是用BT型不育系863A与优质早熟晚粳稻品种8006杂交并回交转育而成的早熟晚粳稻不育系,具有米质较优、不育性稳定、较易制繁种等特点,所配组合结实率和千粒重高、丰产性好、米质较优,具有较好的应用前景。8006A及其与恢复系湘晴配组育成的新组合苏粳优2号(原名T优011)均于2006年1月通过江苏省品种审定。     

优质粳型不育系爱知香A的选育与利用

爱知香A是用日本优质抗病粳稻品种爱知香与BT型不育系六千辛A测交并连续回交转育而成的早熟中粳不育系，具有米质优、抗病性强，农艺性状优良、花粉败育彻底、配合力好等特点，2002年8月通过江苏省技术鉴定，2003年1月通过江苏省品种审定。利用其配制的杂交粳稻新组合香优18(爱知香A/MR18)表现优质，高产，抗病，于2003年1月通过江苏省品种审定。     

Development of Novel Cytoplasmic Male Sterile Source from Dongxiang Wild Rice (Oryza rufipogon)

This study was conducted to develop and characterize a novel cytoplasmic male sterile(CMS)source which was identified from Dongxiang wild rice(Oryza rufipogon)by crossing Dongxiang wild rice as female with Zhongzao 35,an indica inbred variety,as male and continuous backcrossing with Zhongzao 35.Observation under optical microscope manifested that this novel CMS belonged to typical abortion type with less pollen compared with wild abortive type cytoplasm(CMS-WA).Sequential planting showed that this novel CMS has complete and stable male sterility.Testcross experiment showed that all the 24 tested materials including maintainer and restorer lines of CMS-WA and Honglian type cytoplasm(CMS-HL)and other indica inbred varieties are the maintainers with complete maintaining ability,suggesting that this novel CMS has fertility restoration totally different from CMS-WA and CMS-HL and belongs to a novel type of CMS.So far,we only discovered a unique fertility restoration source for this novel CMS.Inheritance analysis showed that the fertility restoration of this CMS was governed by three pairs of independent dominant genes.Prospect for application of this novel CMS system in hybrid rice breeding was also discussed.     

利用轮回选择法创造粳稻三系恢复系的研究

利用8份光温敏核不育粳稻材料及28份北方寒冷稻作区优良粳稻品种(系)作为原始亲本开展轮回选择育种,育成了吉粳85、吉524、E180和E385等4个具有三系恢复基因的粳型恢复系。这些恢复系性状稳定,恢复度好,测交F1代产量优势明显,表明轮回选择为粳稻恢复系选育提供了一条新的技术途径,并使三系杂交稻在北方寒冷稻作区的大面积推广成为可能。     

RFLP mapping of a fertility restorer gene for rice (O. sativa L.) ′BT′ type CMS line

The Boro type (BT) cytoplasmic male sterility (CMS) line is the main CMS type for the utilization of heterosis in japonica rice. There is no restorer gene for BT CMS line in japonica rice and it was all from indica rice. The restorer gene used in China is from an IRRI indica variety, IR 8.     

水稻广亲和恢复系的选育及其利用

选用具有广亲和基因的粳稻品种与籼稻恢复系杂交，成功地将两个基因重组于一体，育成了籼粳中间型的广亲和恢复系，经与三系不育系配组鉴定，杂种优势强、抗性好，已进入扩大示范并展示出应用的前景。同时，也对广亲和恢复系选育提出若干问题，供共同讨论。