水稻黑条矮缩病抗性资源的筛选和抗性QTL的定位

通过水稻黑条矮缩病的田间鉴定发现,分蘖盛期的病状最为显著,是病症观察的最佳时期。对江苏省311份粳稻品种进行重病区田间鉴定试验,未发现对黑条矮缩病毒(RBSDV)免疫的品种。江苏省目前正在推广的24个主栽水稻品种发病率在10.0%～30.0%之间,曾推广的287份粳稻品种中,71.5%的品种发病率在10.0%～29.0%之间,其余品种发病率在29%以上。来源于日本的粳稻品种Koshihikari的黑条矮缩病发病率相对较低,籼稻高产品种桂朝2号为感病品种。利用Koshihikari/桂朝2号RILs群体进行抗RBSDV的基因定位,结果在第3染色体上标记RM7～RM5748之间检测到1个抗黑条矮缩病的QTL,来自Koshihikari的等位基因增强了水稻黑条矮缩病的抗性,携带抗性位点的家系明显提高了对RBSDV的抗性。本研究结果将为研究水稻黑条矮缩病和水稻抗黑条矮缩病分子育种提供重要信息。     

培育抗灰飞虱水稻品种可减轻水稻黑条矮缩病的危害

<正>为分析水稻品种对黑条矮缩病和灰飞虱抗性的关联性,江苏省连云港市农业科学院、江苏徐淮地区连云港农业科学研究所、江苏省现代作物生产协同创新中心研究人员对49个品种进行田间接种鉴定、人工接种鉴定、抗生性和排驱性试验。结果表明,田间接种中发病率低于20%的品种较多,田间接种鉴定受到外部环境影响因素较大,发病率明显低于     

水稻黑条矮缩病抗性QTL定位

发掘水稻黑条矮缩病的抗性基因有助于抗病品种的选育,减少黑条矮缩病对水稻生产的危害。本研究构建了包含222个家系的L5494/IR36重组自交系群体。对该群体进行黑条矮缩病的田间诱发鉴定,抗性亲本IR36发病率为28.70%,感病亲本L5494发病率为84.26%,群体发病率范围为11.21%～89.81%。利用134对分子标记构建覆盖12条染色体的遗传连锁图谱,总遗传距离为1475.97 cM,平均标记间距为11.1 cM。利用QTL IciMapping 4.0对抗黑条矮缩病QTL进行分析,共检测到4个QTL,其中第1、第2、第9染色体上QTL的表型贡献率分别为12.64%、16.00%和8.43%,抗病等位基因来自抗病亲本IR36;第6染色体上QTL的表型贡献率为10.82%,抗病等位基因来自感病亲本L5494。在此基础上,利用93-11为供体、日本晴为背景的近等基因系材料,在qRBSDV-1定位区间内检测到来自93-11的抗性QTL。本研究结果为水稻黑条矮缩病抗性基因定位及分子标记辅助选择育种提供借鉴。     

水稻品种‘连粳7号’对黑条矮缩病的抗性分析

为分析水稻品种‘连粳7号’对水稻黑条矮缩病的抗性,获得与抗性基因紧密连锁的分子标记,通过田间自然接种和室内人工接种方法,对‘连粳7号’及其与感病品种‘培矮64’衍生来的F_2:3群体进行黑条矮缩病抗性鉴定。结果表明,‘连粳7号’发病率最高为12.25%,最低为5.5%。‘连粳7号’的亲本中,仅‘中粳川-2’的抗性与‘连粳7号’相近。另外,‘连粳7号’对灰飞虱不具有抗性,所以‘连粳7号’对黑条矮缩病的抗性是品种本身对病毒的抗性所致。连粳7号/培矮64 F_2:3群体中,各个家系表型呈现连续分布,并具有超亲分离特点,说明抗性由多基因控制。最终,通过BSA法获得与抗性位点紧密连锁的标记RM287。综上,‘连粳7号’对黑条矮缩病具有较强抗性,抗性来自亲本‘中粳川-2’,标记RM287将为利用分子标记辅助培育抗黑条矮缩病水稻新品种提供有力工具。     

水稻黑条矮缩病抗性QTL分析

利用珍汕97B/明恢63的重组自交系群体,采用自然发病鉴定的方法,以穴发病率为表型值,对各株系进行黑条矮缩病抗性鉴定。群体的穴发病率偏向于抗病亲本,且呈连续性分布,表明水稻黑条矮缩病抗性受数量性状基因控制。利用WinQTLcart 2.5软件对黑条矮缩病抗性QTL进行分析,共检测到6个QTL,其中第6、11染色体上各有2个,第7、9染色体各有1个。第6、7、9染色体上的4个QTL在两个地点都能检测到,是稳定表达的QTL,尤其是第6染色体上的2个QTL,LOD值分别为12.09和9.77,贡献率分别为20.20%和18.68%,是主效QTL,能在分子标记辅助选择育种中加以利用。     

以标记辅助选择改良江苏主栽粳稻品种“淮稻5号”黑条矮缩病抗性

水稻黑条矮缩病是由灰飞虱传播的一种病毒病,最近在江苏、浙江等省暴发给水稻生产造成严重威胁。本研究在前期对水稻黑条矮缩病抗性基因初步定位的基础上,针对第6染色体短臂上紧密连锁的两个抗性QTL,以抗性亲本“明恢63”为供体,感病亲本“淮稻5号”为轮回亲本,通过标记辅助选择,构建了携带目标抗性QTL的系列近等基因系。自然接种和人工接种鉴定表明新培育的近等基因系其发病率较对照轮回亲本下降25%左右,抗性得到显著改良。农艺性状调查结果显示大多数近等基因系其生育期、株高及产量构成性状等与轮回亲本相似,表明目标区段存在较少的累赘连锁。此外,对有关如何实现目标QTL的精细定位,以及利用标记辅助选择聚合多个抗性QTL培育抗病品种的策略也进行了探讨。     

植物病毒病发生威胁粮食作物稳产(译)

近年来我国水稻生产上病毒病频繁发生,已对部分地区水稻生产安全造成一定影响,目前在国家区试中已率先启动了水稻条纹叶枯病、水稻黑条矮缩病和南方水稻黑条矮缩病鉴定,本译文旨在介绍当前威胁和有潜在威胁的水稻为主的谷物病毒病生物学特性、传播流行规律、病毒带毒监测技术、病毒的基因功能及其与介体互作分子机制、抗病毒新材料的创制等方面的研究进展,为开展水稻病毒病抗性品种选育及病害防控技术开发相关研究提供参考借鉴.     

普通野生稻对南方水稻黑条矮缩病的抗性机制分析及主效QTL定位

南方水稻黑条矮缩病给水稻生产带来巨大的产量损失,开展水稻对该病的抗性机制分析及抗性基因定位,将为抗病品种培育提供材料基础和理论依据。本研究利用QTL-seq技术结合连锁分析定位抗病野生稻材料Y11的抗性主效QTL。结果表明,Y11对南方水稻黑条矮缩病的抗性源于对病毒的抗性而非抗虫性,属于数量性状。此外,在第6染色体上SSR标记RM20148和RM20297之间检测到一个新的南方水稻黑条矮缩病抗性主效QTL qSRBSDV6。本研究初步阐明了普通野生稻对南方水稻黑条矮缩病的抗性机制,定位到一个新的南方水稻黑条矮缩病抗性主效QTL。研究结果将为南方水稻黑条矮缩病的分子育种奠定基础。     

杂交水稻黑条矮缩病发生为害损失与防治指标研究

根据1998-2003年杂交水稻黑条矮缩病发生为害损失与防治指标研究,测定了杂交水稻不同组合、不同生育期的发病率,以及秧苗期与大田期的侵染机率,分析了杂交水稻黑条矮缩病前后作发病率关系：M=1.6822m+0.1049,以及株发病率(M%)与产量损失率(Y%)的关系：Y=0.9776M-0.1935;阐述了灰飞虱不同虫量(X)与发病率和产量损失率(Y%)的关系：秧苗期为Y1=12.1841X1-1.0784 , 大田前期为Y2=4.5159X2-0.4620。在拟定经济允许损失水平的基础上,提出杂交水稻秧苗2-5叶期和大田初期为防治适期,并制定杂交水稻黑条矮缩病的策略性防治指标为前作穗期防治的黑条矮缩病株发病率1.0%,制定秧苗期防治指标为带毒灰飞虱0.15只/0.11m2、大田初期防治指标为带毒灰飞虱4000只/667m2(百丛带毒灰飞虱20只)。经应用验证,与实际基本吻合。     

气象因素对南方水稻黑条矮缩病的影响及预测模型的创建

南方水稻黑条矮缩病是近年来在中国南方稻区新发生的一种重要病毒性病害。为了明确气象因素与发病间的关系,提高预测能力,避免严重的损失,利用化州市2006—2014年的气象数据与南方水稻黑条矮缩病田间实际发生数据,采用逐步回归和通径分析研究了南方水稻黑条矮缩病发病率与气象因素的关系。结果表明：6月中旬至7月上旬降水日数、6月下旬至7月上旬相对湿度和8月上旬平均最高气温等3个气象因子对南方水稻黑条矮缩病发病率影响最为关键。利用气象因子建立了南方水稻黑条矮缩病发病率回归模型为：y?＝-531.9999-4.4850x1+1.0238x2+3.6891x3+7.0837x4+1.0286x5-2.8431x6,利用该回归方程对历史资料的拟合效果非常好,预测能力强,适宜于化州本地乃至粤西地区。     

利用MR1523/苏御糯F_(2:3)群体定位水稻抗灰飞虱QTL

灰飞虱是我国水稻生产的主要害虫之一,不仅直接取食危害水稻,还是水稻主要病毒病的传播介体,严重制约水稻生产。籼稻品种MR1523对灰飞虱表现较强的排趋性。为发掘抗灰飞虱新基因,本研究利用MR1523与感虫粳稻品种苏御糯构建了一个包含200个家系的F2:3分离群体,进行灰飞虱抗性鉴定。并利用120对均匀分布在水稻12条染色体的多态性SSR标记,构建了全基因组连锁图谱,进行抗灰飞虱QTL定位。结果分别在水稻第2、第5和第6染色体上检测到Qsbph2、Qsbph5a、Qsbph5b和Qsbph6 4个抗灰飞虱QTLs,分别位于分子标记RM526–RM3763、RM17804–RM13、RM574–RM169和RM190–RM510之间,LOD值分别为2.14、3.13、3.23和2.35,贡献率分别为12.0%、14.7%、17.4%和14.1%,各QTL的抗性等位基因效应均来自抗虫亲本MR1523。该结果为后续抗灰飞虱基因的精细定位及通过分子标记辅助选择培育抗灰飞虱水稻新品种奠定了基础。     

利用Mudgo/武育粳3号F2群体分析水稻抗灰飞虱QTL

灰飞虱是我国水稻生产上的重要害虫。Mudgo是一个高抗灰飞虱的籼稻品种,对灰飞虱具有强的排驱性和抗生性抗性。利用Mudgo/武育粳3号F₂群体,构建了含有177个单株的F₂群体的遗传连锁图谱。该连锁图包含104个SSR标记和3个Indel标记,覆盖整个水稻基因组1 409.9 cM,每两个标记之间的平均距离为13.2 cM。采用改进的苗期集团筛选法对177个F_2:3家系进行了抗性鉴定,通过Windows QTL Cartographer 2.5进行复合区间作图分析,在第2、3、12染色体上分别检测到抗灰飞虱QTL Qsbph2b、Qsbph3d和Qsbph12a,分别位于标记RM5791~RM29、RM3199~RM5442和I12-17~RM333 1之间,单个LOD值分别为3.25、3.11和6.82,贡献率分别为17.3%、15.6%和35.8%,各QTL增强抗性的等位基因效应均来自Mudgo。其中Qsbph12a与标记RM3331和I12-17紧密连锁。结合表型鉴定的结果,Qsbph12a应为抗灰飞虱主效QTL,与该位点紧密连锁的标记可用于抗灰飞虱快速选择辅助育种。     

分子标记辅助选育聚合抗稻瘟病基因Pi5及Pita的水稻新品系

稻瘟病是对水稻生产具有严重威胁的真菌病害,选育并推广聚合多个抗稻瘟病基因的抗病品种是防控该病最为经济有效的途径。本研究以携带不同抗稻瘟病基因的‘吉粳105’(Pita)和‘T639’(Pi5)为亲本杂交衍生的后代群体为试材,利用分子标记辅助育种技术,筛选到3个聚合抗稻瘟病基因Pita和Pi5的后代。并以其中一个株系‘吉2011TK50’为试验材料,利用人工接种鉴定、显微观察及定量PCR等技术研究‘吉2011TK50’的抗病表型及抗性分子机制。结果表明,抗稻瘟病基因的聚合能够增强该品系对稻瘟病的抗性。显微观察和抗稻瘟病基因表达分析发现,基因聚合株系在接种稻瘟病菌后24 h PR基因表达量显著升高,被稻瘟病菌侵染的细胞开始出现过敏性死亡等抗病反应,抑制了稻瘟病菌的进一步侵染。研究结果证实聚合Pita和Pi5可提高水稻品种对抗稻瘟病的抗性,这可为抗病基因聚合育种提供参考。     

水稻恢复系C224抗条纹叶枯病相关QTL的检测

在实验室采用人工接种方法鉴定了亲本及192个99B/C224杂交后代F2∶3家系对水稻条纹病毒的抗性,表型值用条纹叶枯病病情指数表示,利用QTL IciMapping软件,采用完备区间作图法分析水稻条纹叶枯病抗性基因,共检测到5个QTLs:分别为qstv1、qstv2、qstv3-1、qstv3-2和qstv11,位于...     

Screening for Resistance to Bacterial Blight in Upland Cotton (Gossypium hirsatum L.)

Fifty four varieties of upland cotton (Gossypium hirsutum L.) were screened for resistance to bacterial blight caused by Xanthomonas malvacearum E. F. Smith, (Dowson) under natural field conditions and artificial Inoculation. In general, moderately high levels of field infection provided useful information on susceptibility of varieties but 11 needed to be1 supplemented with artificial inoculation to confirm resistance. Hypocotyl regions of one week-old seedlings were subjected to artificial inoculation with bacterial blight crude isolate using hypodermic needles. None of the fifty lour varieties tested was immune to disease 18.5 % showed a high level of resistance, 29.6 % were recorded as resistant while 20.4 % were susceptible. Another 18.5 % were highly susceptible and 13.0 % showed inconsistent disease reaction under natural field conditions. However, under artificial inoculation the seedlings showed lesions of varied sizes but none of the varieties was found to be resistant. Statistical analysis showed non-significant (P = 0.05) disease interaction indicating susceptibility to disease at the seedling stage. This may be due to lower levels of resistance in seedlings than in mature cotton plants. The resistant varieties were mainly of African origin and well adapted to local conditions. They are therefore potentially useful as commercial varieties in their own right or as donor parents for blight resistance.     

Inheritance of resistance to rice stripe virus in rice line `BL 1'

Rice stripe is the most serious virus disease in temperate rice-growing countries. The most economical and environmentally safe practice for controlling this disease is virus-resistant cultivars. ‘BL 1’ is an elite germplasm line with the blast resistance gene Pib, and has been used as a differential line for testing the pathogenicity of the blast fungus. We found that certain progenies from BL 1 showed resistance to both blast and rice stripe virus (RSV). The objectives of this study were to evaluate the RSV resistance in the field and under artificial conditions, to assess the reaction to the insect vector(small brown plant hopper, SBPH), and to examine its inheritance and its relationship to blast resistance in BL 1.BL 1 was susceptible to SBPH, but resistant to RSV in field and artificial inoculation tests. The inheritance of RSV resistance in F₃ lines from the cross Nipponbare (NPB)/BL 1 was studied using artificial inoculation with a population of viruliferous SBPH. A serological assay for RSV infection using an enzyme-linked immunosorbent assay (ELISA) was used. RSV resistance in BL 1 was controlled by a single major gene with incomplete dominance. The locus responsible for RSV resistance was genetically independent of the blast resistance gene Pib. The resistance gene for RSV infection in BL 1 was also independent of Stvb-i, a gene widely distributed in resistant Japanese cultivars. Resistance to RSV must be diversified in rice cultivars considering the potential for future emergence of new RSV strains. The new resistance gene identified in BL 1, which has improved plant type and blast resistance, is considered useful for breeding RSV-resistant cultivars in japonica rice. This revised version was published online in August 2006 with corrections to the Cover Date.     

寒地水稻优质稻米抗稻瘟病性鉴定研究

通过人工接种和自然感病两种方法,共鉴定寒地水稻新品种(系)292份(次),鉴定出高抗新品种(系)22份,适合寒地稻区种植的优质、抗病、农艺性状优良的新品种（系）7份,扩大和充实了抗病基因库。     

应用相对抗病性指数评价胡萝卜种质资源黑腐病抗性

研究旨在建立胡萝卜苗期黑腐病品种抗病性鉴定方法,并筛选出胡萝卜黑腐病抗病种质资源。通过连续2年同一地块苗期人工喷雾接菌方法对胡萝卜种植资源进行胡萝卜黑腐病抗性鉴定,应用相对抗病性指数和聚类分析方法建立品种抗病性评价标准,对供试品种进行品种抗病性分析。依据相对抗病性指数进行聚类分析,确定胡萝卜黑腐病品种抗性类型划分标准为：高抗(HR),RRI≥1.4;抗病(R),1.1≤RRI＜1.4;中抗(MR),0.5≤RRI＜1.1;感病(S),0.1≤RRI＜0.5;高感(HS),RRI＜0.1。供试11个品种中高抗品种2个、抗性品种3个、中抗品种3个、感病品种1个、高感品种2个。试验建立了胡萝卜品种田间抗病性鉴定方法和评价标准,可为胡萝卜抗病育种研究和田间种植品种选择提供理论依据。     

不同土壤对元阳传统水稻品种稻瘟病抗性的影响

为研究不同品种水稻稻瘟病发病情况与土壤理化特性的相关性,本研究以元阳传统水稻品种‘月亮谷’为主要研究对象,分别将‘月亮谷’和‘日本晴’种植于元阳梯田土和温室土中,‘月亮谷’、‘红阳3号’、‘蒙古稻’、‘日本晴’和‘越光’种植于元阳梯田土和东港稻田土中,在水稻生长到三叶一心期时,进行稻瘟病接菌处理,同时对种植土壤理化性质进行测定,分析各理化指标与不同水稻品种稻瘟病病情指数的相关性。结果表明,‘日本晴’在两种土中的稻瘟病病情指数为29.07%和29.63%,是‘月亮谷’的两倍(12.04%,14.81%);元阳梯田土有效磷含量与‘月亮谷’‘日本晴’病情指数相关性指数分别为-0.945,-0.946。东港稻田土有效磷含量是元阳梯田土的2.68倍,呈极显著差异(p<0.01)。‘月亮谷’、‘红阳3号’、‘蒙古稻’病情指数在东港稻田土中分别比在元阳梯田土中增加了10%、25%、15%,‘越光’‘日本晴’分别降低了7%、15%。元阳水稻品种在元阳梯田土中均发病较低,而在东港土中发病程度加剧。说明稻瘟病的发生与水稻的品种,土壤pH值、有机质含量以及碱解氮均有显著的相关性。本试验为进一步研究元阳梯田土壤与当地水稻品种抗稻瘟病之间的关系提供了理论基础、明确了梯田土壤对当地水稻品种抗稻瘟病的促进作用。     

Evaluation of whitefly-mediated inoculation techniques to screen Lycopersicon esculentum and wild relatives for resistance to Tomato yellow leaf curl virus

For two consecutive years nine hybrids and three varieties of tomato, four Lycopersicon peruvianum and four Lycopersicon chilense accessions were screened for Tomato yellow leaf curl virus (TYLCV) resistance. Three inoculation techniques using Bemisia tabaci, the vector of TYLCV, were compared: (1) artificial mass inoculation-simultaneous infection of cultivated and wild material in greenhouses; (2) artificial cage inoculation-individual infection in insect-proof cages; (3) natural field infection. Artificial inoculations led to higher levels of infection, but different patterns of response to each inoculation technique were found depending on the resistance level. Tomato varieties showed an important fruit set reduction after both artificial and natural inoculations. In contrast, field infection was milder in tomato hybrids, in which yield was barely affected. These hybrids showed a wide range of reactions with the two artificial inoculation techniques, but infection was always more severe after mass inoculation. Extreme severity of mass infection made it difficult to differentiate among variable degrees of resistance that were more reliably detected with cage inoculation. The hybrids F3524, F3522, Fiona, and Tyking showed the highest level of resistance. F3524 and F3522 had an acceptable yield in field and cage assays, but their resistance collapsed under massive conditions of infection. Tyking and Fiona exhibited the best response in all conditions, although their yield was moderately reduced in mass assays. Mass inoculation was not adequate for the screening of wild Lycopersicon. Some susceptible plants escaped infection, probably as a consequence of non-preference mechanisms and loss of vector infectivity. Individual inoculation in cages prevented the risk of non-infection, ensuring 100% disease incidence. This technique allowed the selection of highly resistant wild sources. L. chilense LA 1969 and LA 1963 had the highest level of resistance with the three inoculation techniques. L. peruvianum PI-126944 and L. chilense LA 1932, which were only tested in mass and field conditions, also exhibited a promising response. The results proved that the inoculation technique influences the response of tomato and wild Lycopersicon spp to TYLCV. It is concluded that artificial cage inoculation, although more time-consuming, is the most efficient, adequate, and reliable technique to screen both cultivated and wild Lycopersicon species for resistance to TYLCV. This revised version was published online in July 2006 with corrections to the Cover Date.