Study on the control of rice stripe disease with Bilken virusicide

The paper reviewed the function mechanism of Bilken virusicide against rice stipe disease, and then introduced its control effects in field test as well as its application method.

Effect of Rice Sowing Date on Occurrence of Small Brown Planthopper and Epidemics of Planthopper-Transmitted Rice Stripe Viral Disease

To understand the relationship between rice sowing date and occurrence of the rice small brown planthopper （SBPH） Laodelphax striatellus Fallen and the epidemics of the planthopper-transmitted rice stripe viral （RSV） disease, four sowing dates of rice were evaluated in 2006 and 2007. The results showed that the peak density of SBPH and RSV incidence in the nursery and in the transplanted field decreased with the delay of sowing date in single crop of japonica rice in north Zhejiang Province of China. The relationship between seedling RSV incidence at the end of the nursery trial with sowing date was well described by Weibull equation. The area under the curve of population dynamics （AUCPD or planthopper-day accumulation） or the peak density of the planthopper in the nursery could be summarized by a logistic equation. RSV incidence in the transplanted fields could be characterized quantitatively by a multivariate regression equation, including the variables of sowing date, peak density of the vector, and RSV incidence at the end of the nursery trial. That the descriptive model excluded the AUCPD in transplanted field implies that this variable is not necessary in forecasting disease epidemics in the field. The 2-year experiments sufficiently indicated that suitable sowing of rice could be used as one of the effective measures to control the vector population and therefore the planthopper-transmitted RSV on a larger scale. The optimal sowing date for the single-cropped transplanted japonica rice is recommended from late May to early June in north Zhejiang, China.

Genetic Improvement of Japonica Rice Variety Wuyujing 3 for Stripe Disease Resistance and Eating Quality by Pyramiding Stv-b^i and Wx-mq

Japonica rice variety Kanto 194 as the donor of resistance gene Stv-b^i and Iow-amylose content gene Wx-mq was used to improve the resistance and eating quality of Wuyujing 3 by the breeding strategy of backcross. In continuous backcross and selfcross generations, the related molecular markers with Stvobi and Wx-mq genes were utilized for genotypic detection by associated with resistance identification of rice stripe disease and agronomic traits selection. Finally, 10 improved lines with homozygous genotype Stv-b^i Stv-b^iWx-mqWx-mq were obtained from BC3F4 generation. The results of comparative analysis indicated that most characters of these lines were consistent with those of recipient parent Wuyujing 3, except for the improved resistance, appearance and eating quality. By evaluation of the comprehensive performance of them, two excellent lines K01 and K04 were selected for further experiments.

Detection,Occurrence,and Survey of Rice Stripe and BlackStreaked Dwarf Diseases in Zhejiang Province,China

The major viral diseases that occur on rice plants in Zhejiang Province, eastern China, are stripe and rice black-streaked dwarf diseases. Rice stripe disease is only caused by rice stripe tenuivirus （RSV）, while rice black-streaked dwarf disease can be caused by rice black-streaked dwarf fijivirus （RBSDV） and/or southem rice black-streaked dwarf fijivirus （SRBSDV）. Here we review the characterization of these viruses, methods for their detection, and extensive surveys showing their occurrence and spread in the province.

Transferring Translucent Endosperm Mutant Gene Wx-mq and Rice Stripe Disease Resistance Gene Stv-bi by Marker-Assisted Selection in Rice (Oryza sativa)

A high-yielding japonica rice variety, Wuyunjing 7, bred in Jiangsu Province, China as a female parent was crossed with a Japanese rice variety Kantou 194, which carries a rice stripe disease resistance gene Stv-b＇ and a translucent endosperm mutant gene Wx-mq. From F2 generations, a sequence characterized amplified region （SCAR） marker tightly linked with Stv-b＇ and a cleaved amplified polymorphic sequence （CAPS） marker for Wx-mq were used for marker-assisted selection. Finally, a new japonica rice line, Ning 9108, with excellent agronomic traits was obtained by multi-generational selection on stripe disease resistance and endosperm appearance. The utilization of the markers from genes related to rice quality and disease resistance was helpful not only for establishing a marker-assisted selection system of high-quality and disease resistance for rice but also for providing important intermediate materials and rapid selection method for good quality, disease resistance and high yield in rice breeding.

Disaster Prevention and Mitigation Technologies of Rice Virus Diseases Spread by Small Brown Planthopper (SBPH)

Rice stripe virus disease （RSVD） and rice black-streaked dwarf virus disease （RBSDVD） are two epidemic diseases in Yancheng City, Jiangsu Province in the last decade. The authors investigated the disaster regularity, prevention and control technology of RSVD and RBSDVD systematically. The occurrence and virus transmission of SBPH and disaster regularity of virus diseases were studied; the resistance of some rice varieties was cleared; the effects of physical and agricultural measures such as insect net blocking, appropriate late sowing and plowing on controlling occurrence and virus transmission of SBPH were figured out; a hatch of chemical agents were screened, providing efficient and harmless pesticides for effective control against SBPH and prevention against virus diseases. A set of disaster control and mitigation technologies was proposed in this paper, which was practical, sustainable, and easy to operate for the local planting patterns.

湖南省道县水稻叶条斑病病原菌分离与鉴定

【目的】2023年6月在湖南省永州市道县仙子脚镇多个村的水稻上发现一种叶条斑病,发生面积超过30 hm^(2),为探究发病原因,开展相关研究。【方法】利用组织分离法对道县采集的水稻病叶进行病原菌分离,对分离到的病菌进行形态学观察,结合ITS、TEF1-α和TUB2基因序列联合建树,确定病原物,利用柯赫氏法则进行病原物验证。【结果】湖南省永州市道县仙子脚镇发生的水稻叶条斑病病原菌为稻黑孢(Nigrospora oryzae)。【结论】明确了湖南省道县水稻叶条斑病的病原菌,为今后防控工作的开展提供参考。

Interaction between Rice stripe virus Disease- Specific Protein and Host PsbP Enhances Virus Symptoms

Rice stripe virus （RSV） causes severe diseases in Oryza sativa （rice） in many Eastern Asian countries. Diseasespecific protein （SP） of RSV is a non-structural protein and its accumulation level in rice plant was shown to determine the severity of RSV symptoms. Here, we present evidence that expression of RSV SP alone in rice or Nicotiana benthamiana did not produce visible symptoms. Expression of SP in these two plants, however, enhanced RSV- or Potato virus X （PVX）- induced symptoms. Through yeast two-hybrid screening, GST pull-down, and bimolecular fluorescence complementation assays, we demonstrated that RSV SP interacted with PsbP, a 23-kDa oxygen-evolving complex protein, in both rice and N. benthamiana. Furthermore, our investigation showed that silencing of PsbP expression in both plants increased disease symptom severity and virus accumulation. Confocal microscopy using N, benthamiana protoplast showed that PsbP accu- mulated predominantly in chloroplast in wild-type N. benthamiana cells. In the presence of RSV SP, most PsbP was recruited into cytoplasm of the assayed cells. In addition, accumulation of SP during RSV infection resulted in alterations of chloroplast structure and function. Our findings shed light on the molecular mechanism underlying RSV disease symptom development.

两种药剂对水稻细菌性条斑病的防治效果研究

【目的】验证碧生(20%噻唑锌悬浮剂)对水稻细菌性条斑病的防治效果。【方法】将碧生与当地种植户常使用的辛菌胺醋酸盐细菌剂的方法进行对比,在湛江市文竹村选择近3年发病较重的水稻田开展相关试验。【结果】使用碧生和辛菌胺醋酸盐细菌剂分别在水稻封行期、分蘖末期、破口期进行施药试验,其中使用碧生对水稻细菌性条斑病的防治效果比辛菌胺醋酸盐细菌剂的更好,防效可达63.28%,且处理后水稻产量(干重)最高,为577 kg,同时还能提高水稻产量和有效控制细条病的蔓延。【结论】浙江新农化工股份有限公司自主研发的碧生(20%噻唑锌悬浮剂)可广泛应用于防治细菌性病害,如水稻细菌性条斑病,从作物苗期开始,整个生育期都可用药,具有很高的安全性且效果非常理想。

水稻播种期对灰飞虱及其传播的条纹叶枯病发生流行的影响

【目的】了解水稻播种期对灰飞虱及其传播的条纹叶枯病发生流行的影响。【方法】2006～2007年2年田间设置4个播种期,调查分析水稻灰飞虱种群动态和条纹叶枯病发病的程度。【结果】播种期是影响条纹叶枯病的重要因子。在浙江北部,单季晚稻随着播种期的推迟,病情递减;秧田期株发病率与播种期的关系可以Weibull方程来描述、与秧田期灰飞虱种群动态曲线下面积(AUCPD,即累计虫日)或高峰期密度则呈Logistic关系;本田稳定期发病率则可以以播种期、秧田期灰飞虱高峰期密度、秧田末期的株发病率来描述,而本田期的AUCPD并不是描述该阶段的发病率的必要变量。【结论】在综合治理中,适期播种是控制该病害流行的最有效方法之一,在浙江北部单季粳稻移栽的适宜播种期为5月底～6月上旬。

抗条纹叶枯病香稻新品种的分子标记辅助选育

为解决上海主栽水稻品种普遍对条纹叶枯病缺乏抗性、大多数品种成熟期偏晚且食味品质不佳的状况,该研究以高产、广适性粳稻品种‘武运粳7号’为母本,与高抗条纹叶枯病水稻品系‘武2699’进行杂交,获得F1种子,再以早熟、香型优质品种‘太湖香粳’为父本,与(‘武运粳7号’ב武2699’)F_1进行复交,开展聚合育种;并分别利用与水稻抗条纹叶枯病基因QSTV-11b紧密连锁和香味控制基因Badh2共分离的分子标记,对分离世代进行辅助选择,筛选到含这2个基因的纯合基因型单株,结合田间抗性鉴定及香味测定,育成具有香味、高抗水稻条纹叶枯病、高产、优质等特点的早熟晚粳新品种‘沪香粳151’。

水稻条叶枯病毒(RStV)基因组组分4的克隆与序列分析

利用ＲＴＰＣＲ技术合成并扩增了水稻条叶枯病毒（ＲＳｔＶ）中国云南分离物基因组组分４的全长ｃＤＮＡ，将ＰＣＲ产物克隆在载体ｐＣＲＩ上，并进行全序列测定，所得核苷酸序列及推测的氨基酸序列与日本分离物Ｔ进行比较。结果表明，在核苷酸水平，两分离物的ｖＯＲＦ、ｖｃＯＲＦ及基因间非编码区序列的同源性分别为９４９％、９４１％、８６１％，５’端非编码区序列相同，而３’非编码区同源性为９６１％，仅有两个核苷酸不同；在氨基酸水平，ｖＯＲＦ及ｖｃＯＲＦ编码蛋白的同源性分别为９９４％和９８３％。可见，编码区的大小及其氨基酸序列和两末端序列都是很保守的。因此，中国云南分离物Ｙ与日本分离物Ｔ可能有很近的亲缘关系。

稻鸭共作对水稻条纹叶枯病发生规律的影响

由灰飞虱传毒危害的水稻条纹叶枯病是近年来在我国部分稻作区严重发生的病毒病害.作为稻作生产生态实践模式之一的稻鸭共作技术对稻田病虫草具有显著的控制效应,然而目前还没有关于稻鸭共作对灰飞虱和条纹叶枯病影响的报道.因此,于2004～2005年在南京农业大学东台试验场进行了田间实验,共设计了4个处理,分别为常规稻作区（不养鸭、施药）、稻鸭共作区（养鸭、不施药）和秧田期覆盖防虫网、栽后大田稻鸭共作区（秧田覆盖防虫网、栽后稻田养鸭、不施药）和对照区（不养鸭、不施药）.结果表明：稻鸭共作以及秧田期覆盖防虫网、栽后大田稻鸭共作处理对灰飞虱有显著的控制效应,因此也显著降低了两处理在水稻整个生长期间条纹叶枯病的发病率;稻鸭共作处理对条纹叶枯病的综合防效为79.44﹪,略高于常规稻作78.82﹪的防效,而秧田期覆盖防虫网、栽后大田稻鸭共作处理对稻田灰飞虱和条纹叶枯病的防治效果最好,对条纹叶枯病的防效超过94.01﹪.总之,通过以上试验结果可知,稻鸭共作尤其是秧田期覆盖防虫网、栽后稻鸭共作处理为防治条纹叶枯病提供了一条安全高效的生态控制途径.

水稻条纹叶枯病抗性育种研究

利用日本育成的抗条纹叶枯病优质粳稻品种,与江苏高产品种杂交,将其条纹叶枯病抗性导入江苏高产粳稻品种,达到有利基因的聚合,改良现有粳稻品种的条纹叶枯病抗性。结果表明,在充分发病的自然条件下对条纹叶枯病抗性选择的效果十分明显,只要具有一定的选择压,很容易选择到抗性好的株系。关东194是一个优良的条纹叶枯病抗源亲本,在粳稻条纹叶枯病抗性改良和品质改良中值得加以利用。通过连续3年的定向选择,已经获得一批抗条纹叶枯病的优良品种(系)。其中"宁4009"已于2007年1月通过江苏省审定,定名为"南粳44"。

利用分子标记辅助选择聚合水稻抗病基因Pi-ta、Pi-b和Stv-b^i

水稻稻瘟病和条纹叶枯病是长江中下游粳稻稻区两大主要病害,选育抗病品种是防治这两大病害最有效的方法。以同时含有稻瘟病抗病基因Pi-ta和Pi-b的武运粳8号,含有条纹叶枯病抗病基因Stv-bi的镇稻42为基因供体配置杂交组合。利用Pi-ta和Pi-b的基因标记和Stv-bi紧密连锁的分子标记对分离世代进行基因位点的检测,结合田间多代选育、抗性鉴定将3个抗病基因同时转育到高产品种中,选育出高产、优质、多抗水稻新品系74121。利用分子标记辅助选择,为选育多抗水稻新品种提供了一种简单、快捷的选择方法,同时也为水稻抗病育种提供了新的遗传资源。

主栽品种镇稻88对水稻条纹叶枯的抗性特征及其遗传研究

【目的】明确镇稻88对水稻条纹叶枯病的抗性特征及其抗性遗传模式,寻找与抗条纹叶枯病基因连锁的分子标记。【方法】利用单分蘖鉴定、苗期接种鉴定、非嗜性测验和抗生性测验分析镇稻88对水稻条纹叶枯病和介体灰飞虱的抗性;分别采用单分蘖鉴定和苗期接种鉴定方法对武育粳3号与镇稻88构建的F2群体、F2:3家系进行水稻条纹叶枯病抗性遗传分析;以SSR标记连锁分析方法对抗病基因进行定位。【结果】镇稻88表现出较强的病毒抗性和较弱的抗虫性;其对水稻条纹叶枯病的抗性表现为显性单基因的遗传模式;SSR标记分析显示该抗病基因位于水稻第11染色体上,与标记RM229间的遗传距离为4.7cM。【结论】镇稻88对水稻条纹叶枯病的抗性主要来自于对病毒的抗性,由一对主效核基因控制,以镇稻88为抗病亲本结合本研究结果,可望加快水稻条纹叶枯病抗性品种选育的速度。

分子标记辅助选择改良武育粳3号的条纹叶枯病抗性

在对抗水稻条纹叶枯病品种Dular进行抗性基因定位的基础上,以它为抗性供体亲本,武育粳3号为抗性受体亲本,通过杂交和回交,从BC1F1开始利用与条纹叶枯病抗性QTLqSTV-11b和qSTV-11c紧密连锁的4个分子标记进行辅助选择,改良武育粳3号的条纹叶枯病抗性和选育抗病新品种。对检测到抗病基因的回交后代进行主要性状的聚类分析,分别有9个抗病基因纯合的BC3F2单株和31个抗病基因杂合的BC4F1单株与武育粳3号聚为一类。经进一步纯合稳定,有望筛选到抗性得到改良、性状回复到武育粳3号的株系。对18个抗病基因纯合的BC2F3株系进行鉴定,其条纹叶枯病的抗性均达到抗的水平,有5个株系丰产性较武育粳3号有明显提高,其中2个株系外观品质也较武育粳3号有了明显改进,达到国家优质稻谷标准。

分子标记辅助选择聚合水稻暗胚乳突变基因Wx-mq和抗条纹叶枯病基因Stv-b^i

以江苏高产粳稻品种武运粳7号为母本,具有条纹叶枯病抗性基因Stv-bi和暗胚乳突变基因Wx-mq的日本粳稻品种关东194作父本配制杂交组合进行聚合育种。利用与Stv-bi基因共分离的SCAR标记及与暗胚乳突变基因Wx-mq紧密连锁的CAPS功能标记对其分离世代进行标记位点的检测,结合田间多代选育、抗性鉴定和籽粒胚乳外观鉴定,将条纹叶枯病抗性基因Stv-bi和暗胚乳突变基因Wx-mq同时转育到高产品种中,筛选、培育出优质、抗病、高产且农艺性状优良的水稻新品系宁9108。利用与水稻优质及抗病基因紧密连锁的分子标记,不仅初步建立了优质、抗病育种的分子标记辅助选择体系,也为水稻优质、抗病、高产育种提供了一种简单、快捷的选择方法和重要的中间材料。

江苏省主栽水稻品种对条纹叶枯病与灰飞虱的抗性评价

为明确江苏省主栽抗病粳稻品种对条纹叶枯病的抗性特征,采用苗期接种鉴定、非嗜性测验和抗生性测验的方法,分析了8个主栽抗病品种对水稻条纹病毒和介体灰飞虱的抗性。结果发现:品种的抗病性和抗虫性表现并不一致。抗病性分析发现,供试品种均抗条纹病毒;抗虫性分析发现,镇稻88等4个品种表现为较弱的抗虫性,其余品种均表现为无抗虫性。表明:供试抗病品种对水稻条纹叶枯病表现的抗性主要来源于对条纹病毒的抗性。

以分子标记辅助选择育成抗条纹叶枯病水稻新品种“武陵粳1号”

条纹叶枯病是21世纪以来江苏省最重要的水稻病害之一。食味品质较优的主栽品种武育粳3号因高度感染该病而种植面积锐减。本研究以镇稻88为抗条纹叶枯病毒病基因Stvb-i的供体亲本,采用回交育种策略,改良武育粳3号的抗条纹叶枯病性能。在连续回交和自交过程中,以紧密连锁的双侧分子标记对Stvb-i进行"前景"选择,同时对后代与轮回亲本遗传背景的相似程度进行分子标记辅助"背景"选择,在短期内育成抗条纹叶枯病的"武育粳3号",命名为"武陵粳1号"。新品种保持了原品种的基本农艺性状、丰产性、稳产性和优异的食味品质,并大幅度提高了其条纹叶枯病抗性水平,在江苏省多点抗性鉴定试验中的平均病株率仅为4.4%,极显著低于原品种(53.2%)。