安仁基点水稻新品种抗白叶枯病研究进展

湖南省农科院水稻研究所安仁基点通过对水稻白叶枯病的多年研究,找到了水稻白叶枯病的发生规律,提出了以选用抗病、优质、高产品种为中心,以栽培管理为基础,药剂防治为辅的防治措施;鉴定了白叶枯病材料5万多份,筛选出高抗材料100多份,抗病材料500多份;在此基础上,选育出了一批多抗性品种在生产上应用,产生了很好的社会、经济及生态效益。认为筛选抗源、选育抗多种病、虫的抗性品种仍是今后育种的重要目标。     

水稻白叶枯病(Xanthomonas campestris pv.oryzae)抗性遗传研究 Ⅱ.水稻品种对五个菌系的抗性遗传分析

研究了5个水稻品种邳早15、蚌珠芒、南粳15、中百4号和青华矮6号对3个水稻白叶枯病菌系的抗性遗传和抗性基因等位关系。这5个品种分别与感病品种沈农1033杂交,对各组合的F_1、F_2和B_1F_1群体的抗性测试表明:邳早15和蚌珠芒由一对显性基因控制其抗性。南粳15和中百4号均由两对连锁的显性基因控制,交换值为30%。等位性测定表明:邳早15和蚌珠芒的一对显性基因与Xα-3等位,南粳15和中百4号也均有一对显性基因与Xα-3等位;青华矮6号的一对不完全显性基因与Xα-4是等位的。     

水稻白叶枯病(Xanthomonas campestris pv．oryzae)抗性遗传研究:II．水稻品种对五个菌系的抗性遗传分析

 研究了5个水稻品种邳早l5、蚌珠芒、南粳l5、中百4号和青华矮6号对3个水稻白叶枯病菌系的抗性遗传和抗性基因等位关系。这5个品种分别与感病品种沈农lO33杂交，对各组合的F1、F2和B1F1群体的抗性测试表明：邳早l5和蚌珠芒由一对显性基因控制其抗性。南粳l5和中百4号均由两对连锁的显性基因控制，交换值为30％。等位性测定表明，邳早15和蚌珠芒的一对显性基因与Xa-3等位，南粳l5和中百4号也均有一对显性基因与Xa-3等位；青华矮6号的一对不完全显性基因与Xa-3是等位的。     

Improvement of Rice Resistance to Sheath Blight by Pyramiding QTLs Conditioning Disease Resistance and Tiller Angle

Rice resistance to sheath blight （SB） is controlled by polygenes or quantitative trait loci （QTLs） and affected by plant morphological traits, qSB-9^TQ and TAG1^TQ, which control SB resistance and tiller angle （TA）, respectively, were employed to test whether the combination of the two genes will further improve rice SB resistance and reduce yield loss rather than only one of them or neither. Using two pairs of near isogenic lines （NILs）, TAC1^TQ was confirmed to contribute to SB resistance. However, its effect was less considerable than that of qSB-9^TQ. Subsequently, the two genes were introduced into two commercial rice varieties to develop a series of NILs. The NILs carrying both TAG1^TQ and qSB-9^TQ showed more resistance than the NILs containing only one of them. Comparing the grain yield per plant （GYP） under the three different SB disease conditions, namely slight, moderate and severe conditions, NILs carrying both genes apparently lost lower GYP than the NILs without the two genes and the NILs carrying only TAC1^TQ. Under slight disease condition, no significant differences were found on morphology, development and GYP associated traits except for TA between the NILs carrying both genes and either of them, indicating that the two genes have no inferior effect on rice agronomic traits. Results indicated that mAC1^TQ and qSB-9^TQ have high breeding potential, and pyramiding SB resistance QTL and morphological trait QTL is a potential approach in improving rice SB resistance.     

Marker-Assisted Pyramiding of Genes Conferring Resistance Against Bacterial Blight and Blast Diseases into Indian Rice Variety MTU1010

Two major bacterial blight(BB) resistance genes(Xa21 and xa13) and a major gene for blast resistance(Pi54) were introgressed into an Indian rice variety MTU1010 through marker-assisted backcross breeding. Improved Samba Mahsuri(possessing Xa21 and xa13) and NLR145(possessing Pi54) were used as donor parents. Marker-assisted backcrossing was continued till BC2 generation wherein PCR based functional markers specific for the resistance genes were used for foreground selection and a set of parental polymorphic microsatellite markers were used for background selection at each stage of backcrossing. Selected BC2F1 plants from both crosses, having the highest recoveries of MTU1010 genome(90% and 92%, respectively), were intercrossed to obtain intercross F1(ICF1) plants, which were then selfed to generate 880 ICF2 plants possessing different combinations of the BB and blast resistance genes. Among the ICF2 plants, seven triple homozygous plants(xa13xa13Xa21Xa21Pi54Pi54) with recurrent parent genome recovery ranging from 82% to 92% were identified. All the seven ICF2 plants showed high resistance against the bacterial blight disease with a lesion lengths of only 0.53–2.28 cm, 1%–5% disease leaf areas and disease scoring values of ‘1' or ‘3'. The seven ICF2 plants were selfed to generate ICF3, which were then screened for blast resistance, and all were observed to be highly resistant to the diseases. Several ICF3 lines possessing high level of resistance against BB and blast, coupled with yield, grain quality and plant type on par with MTU1010 were identified and advanced for further selection and evaluation.     

Genetics and Improvement of Bacterial Blight Resistance of Hybrid Rice in China

Since 1980s,rice breeding for resistance to bacterial blight has been rapidly progressing in China. The gene Xa4 was mainly used in three-line indica hybrid and two-line hybrid rice. The disease has been ‘quiet’ for 20 years in China,yet in recent years it has gradually emerged and been prevalent in fields planted with newly released rice varieties in the Changjiang River valley. Under the circumstances,scientists inevitably raised several questions:what causes the resurgence and what should we do next? And...     

三个粳稻品种的稻瘟和白叶枯病抗性遗传分析

 分析了城特232、嘉23和浙湖8号等3个粳稻品种对稻瘟病菌ZD1、ZE1和ZF1及白叶枯病菌8810-1的抗性遗传,结果表明,3个抗病亲本对ZD1、和ZF1的抗性都带有2对显性重复基因。等位性测定表明其中至少有1对是等位的，对ZE1小种的抗性均受1对显性基因控制，等位性分析三者的抗性基因各不相同。城特232和嘉23对白叶枯病抗性是由1对显性基因控制，而浙湖8号为2对显性互补基因控制。等位性测定表明城特232和嘉23的1对基因是等位的，但与浙湖8号的2对抗性基因是不等位的。推断了抗病亲本的可能的抗性基因。     

三个粳稻品种的稻瘟和白叶枯病抗性遗传分析

分析了城特232、嘉23和浙湖8号等3个粳稻品种对稻瘟病菌ZD_1、ZE_1和ZF_1及白叶枯病菌8810-1的抗性遗传。结果表明,3个抗病亲本对ZD_1和ZF_1的抗性都带有2对显性重复基因,等位性测定表明其中至少有1对是等位的。对ZE_1小种的抗性均受1对显性基因控制,等位性分析三者的抗性基因各不相同。城特232和嘉23对白叶枯病抗性是由1对显性基因控制,而浙湖8号为2对显性互补基因控制。等位性测定表明城特232和嘉23的1对基因是等位的,但与浙湖8号的2对抗性基因是不等位的。推断了抗病亲本的可能的抗性基因。     

Breeding Rice Restorer Lines with High Resistance to Bacterial Blight by Using Molecular Marker-Assisted Selection

Rice bacterial blight, one of the major diseases of rice caused by Xanthomonas oryzae pv. oryzae, Xoo, jeopardizes rice diversely. It causes leaf wilting, affects photosynthesis and reduces 1000-grain weight and generally results in yield loss by 20-30 pe…     

利用分子标记辅助育种技术选育高抗白叶枯病恢复系

通过常规回交育种结合分子标记辅助选择技术,已将来自IRBB24的2个抗白叶枯病基因, Xa21和Xa4, 聚合到感病的杂交稻恢复系绵恢７２５中。通过分子标记检测目标基因和亲本遗传背景差异分析快速获得了4个高抗白叶枯病的恢复系姊妹系R207 1、R207 2、R207 3和R207 4。采用与目标抗性基因相应的菲律宾菌系P1、P6 和7个中国病原型代表菌系（CⅠ~CⅦ）对4个姊妹系及其杂交组合进行田间接种。结果表明,这些姊妹系及所配制的杂交组合抗病性强、抗谱广,其中杂交组合G46A/R207 2具有良好的产量潜力,将R207 2定名为蜀恢207。     

中国杂交水稻白叶枯病抗性的遗传改良

 20世纪80年代,中国杂交水稻抗白叶枯病育种进展迅速。在大面积种植的籼型三系和两系杂交稻中主要应用白叶枯病抗性基因Xa4,白叶枯病在生产中几乎“销声匿迹”了20年。但近年来,此病害却在长江流域一些种植新组合的稻田里又爆发了。什么原因引起它再度流行？品种的抗性是否还有效？抗病育种是否还是水稻改良的主要目标之一？通过哪些途径才能更有效地利用抗病基因培育出更为持久的抗性品种？为回答这些问题,就我国杂交水稻对白叶枯病抗性的改良,寄主与病菌群体的互动演变效应进行了分析,讨论了拓宽抗性遗传基础、白叶枯病菌毒性群体结构、基因轮换、合理利用基因等问题。 在采用了包括传统方法、分子标记辅助选择和转基因技术的综合策略后,杂交水稻抗白叶枯病育种研究将出现新的局面。     

分子标记辅助选择与花药培养相结合快速聚合水稻白叶枯病抗性基因

以受微效多基因控制白叶枯病抗性的五丰占2号和主基因[i]xa5[/i]控制的IRBB5为材料,应用分子标记辅助选择、花药培养和回交技术研究了主基因与微效多基因聚合的途径。经查阅GeneBank中RG556的序列,利用在线引物设计软件Primer 3设计了一条新的R引物：5′CCAGACACCACTGCACATTC3′,克服了原引物Tm值相差太大,扩增效率低的缺点,使PCR扩增效率提高了近10倍。采用病斑长度与五丰占2号相近且携有xa5基因的五丰占2号[sup]2[/sup]/IRBB5 B[sub]1[/sub]F[sub]1[/sub]植株进行花药培养,获得30株二倍体植株,其中16株携有[i]xa5[/i]基因。携有[i]xa5[/i]基因的植株的平均病斑长度仅0.1 cm,对白叶枯病的抗性明显强于双亲。成功地聚合了白叶枯病抗性主基因和微效多基因。从配组到获得主基因和微效多基因聚合材料仅用两年时间,比常规育种方法缩短1~2年。     

Breeding of R8012,a Rice Restorer Line Resistant to Blast and Bacterial Blight Through Marker-Assisted Selection

Genetic improvement is one of the most effective strategies to prevent rice from blast and bacterial blight(BB) diseases,the two most prevalent diseases jeopardizing rice production.Rice hybrids with dural resistance to blast and BB are needed for sustainable production of food.An incomplete diallele design resulted in 25 crosses between five blast and five BB resistant germplasm accessions.Only one pair of parents,DH146 × TM487,showed polymorphism for all the markers to identify one blast resistance gene Pi25 and three BB resistance genes,Xa21,xa13 and xa5,thus it was used in the marker-assisted selection(MAS).F2 individuals of DH146 × TM487 were genotyped using flanking markers of RM3330 and sequence tagged site(STS) marker SA7 for Pi25.The resistant F2 plants with Pi25 were used for pyramiding BB resistance genes Xa21,xa13 and xa5 identified by the markers pTA248,RM264 and RM153,respectively in subsequent generations.Finally,after selection for agronomic traits and restoration ability among 12 pyramided lines,we acquired an elite restorer line,R8012 including all four target genes(Pi25+Xa21+xa13+xa5).Hybrid Zhong 9A/R8012 derived from the selected line showed stronger resistance to blast and BB,and higher grain yield than the commercial checks uniformally in experimental plots,2007 state-wide yield trial and 2008 nation-wide yield trial.This study provides a paradigmatic example to show that MAS is a practically feasible tool in effectively pyramiding multiple resistance genes.The resultant restoring line and its hybrid would play an important role in securing rice production in China.     

抗水稻细条病和水稻白叶枯病转基因水稻植株的获得

抗水稻细条病和水稻白叶枯病转基因水稻植株的获得ＲｅｇｅｎｅｒａｔｉｏｎｏｆＴｒａｎｓｇｅｎｉｃＲｉｃｅＰｌａｎｔｓＲｅｓｉｓｔａｎｔｔｏＢａｃｔｅｒｉａｌＬｅａｆＳｔｒｅａｋａｎｄＢａｃｔｅｒｌａｌＢｌｉｇｈｔｏｆＲｉｃｅ￥中国水稻研究所生物工程系和...     

水稻白叶枯病的抗性遗传研究

 以4个晚粳品种为材料，采用双亲本回交设计对白叶枯病抗性的遗传特性及基因效应作了分析。参试的晚粳品种对两个菌系KS-6-6和浙173的抗性是不完全隐性遗传，符合加性－显性模型；基因的加性效应为极显著，显性效应和上位性效应则皆不显著。加性变异和显性变异并存，但以加性遗传变异为主，表现具有较高的广义、狭义遗传率。菌系Ⅱ与Ⅳ的病级间的关联性表明，晚粳品种嘉23对白叶枯病两菌系的抗性属同一多基因系控制的不完全隐性的数量性状遗传；从有效因子数目估值来看，本研究参试材料至少有一对隐性抗病基因在起作用。     

水稻抗白叶枯病基因定位、克隆及利用研究进展

白叶枯病是水稻生产上主要的细菌性病害之一,严重影响水稻的产量和品质。传统的化学防治和生物防治法收效甚微,利用抗病基因培育抗病品种是最经济、有效和环保的途径。截至目前,从栽培稻和野生稻中鉴定的抗白叶枯病基因有40个,其中32个已被定位,9个已被分离克隆。本文对这些抗白叶枯病基因的定位、克隆、基因特征和作用方式进行了介绍,重点对这些基因在生产上的应用进行了综述,并对水稻白叶枯病抗病育种做出了展望。     

Strategy for Use of Rice Blast Resistance Genes in Rice Molecular Breeding

Rice blast is one of the most destructive diseases affecting rice production worldwide. The development and rational use of resistant varieties has been the most effective and economical measure to control blast. In this review, we summarized the cloning and utilization of rice blast resistance genes, such as Pi1, Pi2, Pi9, Pi54, Pigm and Piz-t. We concluded that three main problems in the current breeding of rice blast resistance are: availability of few R(resistance) genes that confer resistance to both seedling and panicle blast, the resistance effect of pyramided lines is not the result of a simple accumulation of resistance spectrum, and only a few R genes have been successfully used for molecular breeding. Therefore, novel utilization strategies for rice blast R genes in molecular breeding were proposed, such as accurately understanding the utilization of R genes in main modern rice varieties, creating a core resistant germplasm with excellent comprehensive traits, screening and utilizing broadspectrum and durable resistance gene combinations. Lastly, the trends and possible development direction of blast resistance improvement were also discussed, including new genes regulating resistance identified via GWAS(genome-wide association study) and improving rice blast resistance using genetic editing.     

通过分子标记辅助选择技术选育携有水稻白叶枯病抗性基因Xa23的水稻株系

 通过杂交和分子标记辅助选择技术,将亲本材料18113携有的水稻白叶枯病抗病基因Xa23导入亚种间恢复系H705和优质恢复系H706。利用EST标记C189检测目的基因,在18113/H705 F3和18113/H706 F3株系中,分别获得71和52份携有Xa23纯合基因型恢复系。采用水稻白叶枯病Ⅳ型小种代表菌株浙173进行剪叶接种,分别鉴定出61和44份抗病株系,它们的分子标记辅助选择准确率分别为85.92%和84.61%。研究结果表明,C189是检测Xa23基因的有效分子标记之一,不过,其假阳性的几率高于理论交换率的现象还有待于进一步研究。     

Resistance of Antimicrobial Peptide Gene Transgenic Rice to Bacterial Blight

Antimicrobial peptide is a polypeptide with antimicrobial activity. Antimicrobial peptide genes Np3 and Np5 from Chinese shrimp (Fenneropenaeus Chinensis) were integrated into Oryza sativa L. subsp. japonica cv. Aichi ashahi by Agrobacterium mediated transformation system. PCR analysis showed that the positive ratios of Np3 and Np5 were 36% and 45% in T0 generation, respectively. RT-PCR analysis showed that the antimicrobial peptide genes were expressed in T1 generation, and there was no obvious difference in agronomic traits between transgenic plants and non-transgenic plants. Four Np3 and Np5 transgenic lines in T1 generation were inoculated with Xanthomonas oryzae pv. oryzae strain CR4, and all the four transgenic lines had significantly enhanced resistance to bacterial blight caused by the strain CR4. The Np5 transgenic lines also showed higher resistance to bacterial blight caused by strains JS97-2, Zhe 173 and OS-225. It is suggested that transgenic lines with Np5 gene might possess broad spectrum resistance to rice bacterial blight.     

茄子抗青枯病研究现状与展望

茄子青枯病是茄子的主要病害,对茄子的质量和产量造成严重影响。国内外学者已从多个方面对茄子青枯病进行研究,并取得一定的进展。本文对其研究进展进行综述,包括茄子青枯病抗性的遗传规律、抗性品种的筛选和选育、茄子青枯病的综合防治,同时对茄子抗青枯病研究中存在的问题进行了归纳与讨论,并提出一些可行性建议,为以后的研究提供参考。