烟草花叶病普遍率与严重度的关系及感病品种与转基因抗病品系间的比较

 利用田间调查取得的数据,分析了烟草花叶病在转基因抗病品系上和感病对照品种上的普遍率与严重度的关系(I-S)。结果表明感病品种的I-S关系以指数函数拟合较好;在普遍率小于35%左右时可以用直线方程(b₁)拟合。在转基因抗病品系上I-S关系呈现为直线方程(b₂)。b₁、b₂两直线方程的斜率不同,感病品种的斜率显著大于转基因抗病品系的。根据两品种(系)间的I-S关系的显著差异,从流行学角度探讨了转基因抗病品系对压低流行强度的作用、并分别用抗感品种(系)建模以外的另一种数据对利用普遍率估测严重度的可行性进行验证,抗感品种(系)预测的平均准确度分别为85.9%和83.3%。     

稻瘟病普遍率与严重度关系初步探讨

作者对田间自然发病情况的观察和盔栽接种试验,获得92组叶稻瘟和80组穗颈稻瘟普遍率和严重度间对应关系的数据,在计算机上分别分析了叶瘟和穗颈瘟普遍率与严重度之间的关系(I-S)。结果表明:叶瘟I-S关系和穗颈瘟I-S关系均可用直线方程描述,其直线回归方程为:叶瘟:SL=-1.104+0.455IL(SL,IL——叶瘟严重度和普遍率)穗颈瘟:SE=-3.717+0.737IE(SE,IE——穗颈瘟严重度和普遍率)协方差分析结果表明:水稻品种的抗病性对稻瘟病 I-S 关系有一定影响。     

大豆灰斑病叶部病害普遍率与严重度关系初步探讨

 1992~1995年在田间接种条件下对大豆灰斑病叶部发病情况进行系统调查,获得86组感病品种(合丰22)和66组抗病品种(合丰25)普遍率与严重度间对应关系数据,在计算机上分析了两者的关系(I-S关系)。结果表明,感病品种和抗病品种叶部病害的I-S关系均可用直线方程描述,其直线回归方程分别为:#br#SS_感=-2.8029+0.5252IS±6.4364(SS、IS-感病品种严重度和普遍率)#br#SR_抗=-0.3843+0.6334IR±3.7679(SR、IR-抗病品种严重度和普遍率)#br#协方差分析结果表明,大豆品种的抗病性对大豆灰斑病叶部病害的I-S关系有一定影响。     

2011-2020年河南省审定小麦品种抗病性评价

为了解河南省小麦品种抗病性水平,对2011年以来河南省审定的302个小麦品种进行条锈病、叶锈病、纹枯病、白粉病和赤霉病等5种病害的抗病性评价.结果表明,供试材料中具有抗病性的品种数量比例较小,未发现对叶锈病、白粉病和赤霉病表现高抗的品种;65％以上的品种对条锈病、叶锈病、白粉病和纹枯病表现中感,95％以上的品种对赤霉病...     

山西小麦品种和育种材料抗锈病、白粉病鉴定

2011—2015年,采用人工接菌方法,对25个育种单位的601份小麦品种和育种材料进行了小麦条锈病、叶锈病和白粉病的抗病性鉴定,筛选出对小麦条锈病抗性表现良好的品种材料36份,对小麦叶锈病抗性表现良好的品种材料16份,对小麦白粉病抗性表现良好的品种材料12份。     

三唑酮防治成株期小麦条锈病的初步研究

试验结果表明,三唑酮对小麦条锈病防病保产效果好,残效期长,用药量低,安全低毒,内吸传导性能强,使用方法多,是目前比较理想的防锈药剂。在小麦初见剑叶及其前后,病叶率在2～4%时,施药较为适合,每亩用药量7～20克。用此法施药一次,平均防病效果在90%以上,保产效果在13.3～36.2%,平均病指压低在3%以下,可控制整个成株期条锈病危害。中、低和超低容量以及淋浇、泼浇的施药效果与常规叶面喷雾的相似,都是可行的方法。三唑酮还可兼治小麦白粉病和叶锈病。     

小麦条锈菌、叶锈菌和白粉菌混合侵染对病斑扩展的影响

 小麦条锈病、叶锈病和白粉病是小麦主要的叶部病害,它柄在侵染特点、发病规律及危害特性等方面均有许多相似之处。     

83份西农系小麦品种（系）抗性鉴定及抗病基因分子检测

为西北农林科技大学小麦新育成品种（系）在黄淮麦区的大面积推广,该研究对83份西农新育成的小麦品种（系）进行苗期抗条锈病和白粉病鉴定,成株期抗条锈病、白粉病、叶锈病和赤霉病鉴定,并在田间自然环境下对其抗性进行鉴定及对相关抗病基因进行分子检测。结果显示,在苗期人工接种鉴定中,有63、29和16份小麦品种（系）分别对条锈菌Puccinia striiformis f.sp.tritici生理小种CYR32、CYR33和CYR34表现出抗性,9份小麦品种（系）对3个条锈菌生理小种均表现出抗性;有10、3和0份小麦品种（系）分别对白粉菌Blumeria graminis f.sp.tritici生理小种E15、E09和A13表现出抗性。在成株期人工接种鉴定中,有23、15、28和62份小麦品种（系）分别对条锈病、白粉病、叶锈病和赤霉病表现出抗性。在83份小麦品种（系）中有6份在苗期和成株期均对小麦条锈病表现出抗性。在田间抗性鉴定中,有57、6、65和40份小麦品种（系）分别对条锈病、白粉病、赤霉病及叶锈病表现出抗性。在83份小麦品种（系）中,3份含有Yr5基因,22份含有Yr9基因,3份含有Yr17基因,2份含有Pm24基因,14份含有Lr1基因,所占比例分别为3.6%、26.5%、3.6%、2.4%和16.8%。     

水稻不育系粒黑粉病普遍率与严重度间的关系

 稻粒黑粉病(病原菌Neovossia horrida (TaK.)Padw. et A. Kahn)是杂交稻繁殖制种田不育系上的主要病害,流行频率高,危害损失大。普遍率和严重度的关系(I-S关系)是植病流行学观测技术上的一个重要问题。     

2020-2021年河北省审定冬小麦品种抗病性分析

为了解河北省冬小麦品种抗病性水平,以2020-2021年河北省审定的90个冬小麦品种为试验材料,分析其抗病性.结果表明,审定品种抗病性整体水平较低,其中抗条锈病小麦品种占比26.67％,抗白粉病小麦品种占比4.44％,抗叶锈病小麦品种占比6.67％;兼抗条锈病和叶锈病以及兼抗3种病害的品种均为2个.经系谱分析发现,抗条...     

三唑酮(粉锈宁)拌种控制小麦条锈病流行的初步研究

四年试验结果表明,用三唑酮拌种对防治小麦秋苗条锈病,压低田间菌量都有显著作用。这对控制越夏区(包括传播桥梁地带)的菌量保护广大麦区具有实际意义;对翌春条锈病有控制流行的作用,可推迟暴发期8～15天,保产效果为6～15.6％。试验结果还说明,拌种对翌春条锈病的控制作用,是在于压低初始菌量。因此拌种方法,适用于春季菌源以当地为主的地区,适用于春季流行的关键因素是越冬菌量的地区,并且处理的范围越大,越彻底,效果越好。还讨论了用拌种防治秋苗叶锈病和白粉病的作用。     

Genetics of resistance to wheat leaf rust, stem rust, and powdery mildew in Aegilops sharonensis

Aegilops sharonensis (Sharon goatgrass) is a wild relative of wheat and a rich source of genetic diversity for disease resistance. The objectives of this study were to determine the genetic basis of leaf rust, stem rust, and powdery mildew resistance in A. sharonensis and also the allelic relationships between genes controlling resistance to each disease. Progeny from crosses between resistant and susceptible accessions were evaluated for their disease reaction at the seedling and/or adult plant stage to determine the number and action of genes conferring resistance. Two different genes conferring resistance to leaf rust races THBJ and BBBB were identified in accessions 1644 and 603. For stem rust, the same single gene was found to confer resistance to race TTTT in accessions 1644 and 2229. Resistance to stem rust race TPMK was conferred by two genes in accessions 1644 and 603. A contingency test revealed no association between genes conferring resistance to leaf rust race THBJ and stem rust race TTTT or between genes conferring resistance to stem rust race TTTT and powdery mildew isolate UM06-01, indicating that the respective resistance genes are not linked. Three accessions (1644, 2229, and 1193) were found to carry a single gene for resistance to powdery mildew. Allelism tests revealed that the resistance gene in accession 1644 is different from the respective single genes present in either 2229 or 1193. The simple inheritance of leaf rust, stem rust, and powdery mildew resistance in A. sharonensis should simplify the transfer of resistance to wheat in wide crosses.     

The development of the leaf rust,Puccinia hordei,population during winter,spring and early summer in 11 winter barley cultivars

The overwintering and the epidemic development in spring of leaf rust was studied in 11 winter barley cultivars at two different sites near Wageningen in 1976/1977. The amount of leaf rust decreased through the winter at both sites. Cultivars differed considerably in the amount of leaf rust in late winter. Both the moment and the rate of increase of leaf rust after the winter varied with cultivars. The ultimate amount of leaf rust in a cultivar was therefore determined by three factors: The amount of overwintering leaf rust, the onset of leaf rust increase and the rate of increase. The latter was determined by the partial resistance of the cultivar. Why the epidemics did not start at the same moment is yet unknown. The differential overwintering could be explained from the amounts of leaf rust and powdery mildew at the start of the winter, the effect of powdery mildew being a negative one. The correlation coefficient between the values observed in March and those predicted from the December leaf rust and powdery mildew readings was 0.93. In a second experiment carried out in 1979/1980 with six winter barley cultivars chosen from the first experiment the powdery mildew was succesfully excluded by treatment with fungicides. There was no decrease in the leaf rust over the winter nor a differential cultivar effect on overwintering.     

远中5号中来自天兰偃麦草的一个染色体组对三种锈病的抗性作用

 八倍体小偃麦具有偃麦草的抗锈、大穗、多花等优良性状,是小麦育种中的重要种质资源。本研究通过体细胞染色体组型的观察和比较推断八倍体的小偃麦品种远中5号比其变异系多一组来自天兰(中间)偃麦草(Agropyron glaucum)的特有的染色体组EE或FF。远中5号与其变异系之间对三种锈病的抗性差异表明:远中5号对条锈菌七个生理小种(条中22、23、25、26、27、28、29)和对秆锈菌六个生理小种(21C3、34、34C1、34C2、34C4、119)的抗病基因由来自天兰偃麦草的EE或FF染色体组所携带,而在AABBDD染色体组上存在着对叶锈菌四个生理小种(叶中3、4、20、38)的抗病基因。在EE或FF染色体组上也可能含有抗叶锈病的基因,至少由于EE或FF染色体组的存在大大地提高了远中5号对叶锈病的抗病性。     

甘肃平凉苹果病虫害调查初报

采用大面积普查的方法对甘肃省平凉市苹果病虫害的发生种类?发生程度?分布特点?危害程度等进行了系统调查?调查发现全市苹果病虫害至少54种, 其中害虫37种, 病害17种, 优势病虫害9种?苹果树腐烂病?斑点落叶病?花叶病毒病和金纹细蛾是普遍发生的优势病虫害, 以苹果树腐烂病和斑点落叶病发生最重, 前者病株率为19.72%~30.54%, 后者病园率?病叶率和病情指数分别达到95.83%~100.00%?11.11%~95.56%和2.22~34.56; 苹果黑星病?褐斑病?锈病?白粉病和绣线菊蚜是局部发生的优势病虫害, 其中苹果黑星病仅分布于静宁?庄浪和灵台县, 且呈严重发生和迅速扩散态势, 病园率?病叶率?病情指数分别达到66.67%~100.00%?7.26%~35.71%和1.74~10.78, 苹果褐斑病在崆峒?崇信?泾川县(区)重或较重发生, 苹果锈病在泾川?庄浪县较重发生, 苹果白粉病在崇信县中度发生, 苹果绣线菊蚜除在个别果园发生较重外, 整体呈轻度以下发生?由病害引起的苹果叶片提早脱落现象在六盘山以东普遍和严重发生, 落叶率达到11.89%~58.67%, 是影响苹果产量和质量的关键因素之一?     

大叶白蜡树锈病及其重寄生菌研究

 小叶白蜡树锈孢锈菌(Aecidium fraxinibungeanae Diet.)引起大叶白蜡树(Fraxinus chinensis var.rhynchophylla Hemsl)锈病为国内新记录。该锈病在我国重要白蜡产区乐山市严重发生,病株率和病叶率分别可达100%和56%,造成叶片病部坏死,病叶脱落,严重影响白蜡产量。大叶白蜡树锈病菌的重寄生菌(Tuberculina sp.)为国内外首次报道。该重寄生菌在乐山市及雅安市大叶白蜡树锈病菌上寄生很普遍,自然重寄生率达46.8%。重寄生菌寄生在大叶白蜡树锈菌春孢子器(锈子器)出口处,阻碍春孢子(锈孢子)的释放。本文还报道了大叶白蜡树锈病的危害、症状特点、病原形态特征及大叶白蜡树锈病菌的重寄生现象和重寄生菌形态特征。     

Surveys of cereal diseases and pests in the Netherlands. 4. Occurrence of powdery mildew and rusts in winter wheat

Results of annual surveys of winter wheat fields from 1974 to 1986 were compiled to describe epidemics of powdery mildew and rusts in relation to weather and cultivar resistance.An average of 29 and 70% of fields were infected by powdery mildew in May and July, respectively. Mildew prevalence in May was positively correlated with average temperature in October and with average temperature over the months December, January, February and March. In addition, it was correlated negatively with the average grade of mildew resistance of the cultivars sown each year. Prevalence of mildew in July did not show consistent correlations with weather characteristics nor with mildew prevalence in May.Yellow rust was usually not detected in May and on average 18% of the fields was infected in July. The occurrence of yellow rust decreased after 1977, when the farmers adopted cultivars resistant or moderately resistant to yellow rust.Brown rust was usually not detected in May, while in July on average 48% of the fields was infected. Brown rust intensity in July was high in years with a high March temperature and high precipitation during April and May.Black rust was rare in the Netherlands, with 3 and 1% of the fields infected in July 1977 and 1981, respectively.     

The effect of film-forming anti-transpirants on leaf rust and powdery mildew incidence on wheat

Various film-forming anti-transpirants effectively controlled leaf rust and powdery mildew on wheat in the field. Two applications of anti-transpirant emulsions applied after flag leaf emergence were sufficient to suppress leaf rust and powdery mildew on wheat leaves. When applied before, but not after, inoculation anti-transpirant polymers also reduced leaf rust on seedling plants in a growth room experiment.