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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. 相似文献
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Key weather factors determining the occurrence and severity of powdery mildew and yellow rust epidemics on winter wheat were identified. Empirical models were formulated to qualitatively predict a damaging epidemic (>5% severity) and quantitatively predict the disease severity given a damaging epidemic occurred. The disease data used was from field experiments at 12 locations in the UK covering the period from 1994 to 2002 with matching data from weather stations within a 5 km range. Wind in December to February was the most influential factor for a damaging epidemic of powdery mildew. Disease severity was best identified by a model with temperature, humidity, and rain in April to June. For yellow rust, the temperature in February to June was the most influential factor for a damaging epidemic as well as for disease severity. The qualitative models identified favorable circumstances for damaging epidemics, but damaging epidemics did not always occur in such circumstances, probably due to other factors such as the availability of initial inoculum and cultivar resistance. 相似文献
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小麦白粉病与温度的定量关系研究 总被引:5,自引:0,他引:5
温度对小麦白粉病影响试验的结果表明,此病害适宜发生的温度为15~20℃,低于10℃或高于25℃对该病有明显抑制作用。当温度高于26℃时,试验显示随着温度的升高,终止小麦白粉病病程的时间缩短,据此建立了不同温度(x)与相应终止病程的时间(y)的关系模型为y=21 900e-0.303 5x(χ2=1.65<χ20.05,7=14.07)。同时,根据高温区病害的严重度(y)与温度(x)的试验数据,建立了其关系模型为:y=-3.00x+76.60(r2=0.922 1**),由此计算获得了连续10 d(一个病程时间)温度为25.53℃即可终止此病害的病程。该试验结果将为小麦白粉病的越夏区划提供基础数据。 相似文献
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Yoshinori Yamanaka Masaru Moritomo Katsutoshi Fujii Toshinobu Tanaka Yasuhisa Fukuda Keiichiro Nishimura 《Pest management science》1998,54(3):223-229
Members of a new class of fungicide containing benzylaminopyrimidine as a core structure were synthesized and their fungicidal potencies against wheat brown rust, Puccinia recondita, and barley powdery mildew, Erysiphe graminis, were assessed. Among these fungicides, N-(fluoroalkoxy or fluorophenoxybenzyl)-4-pyrimidinamines showed notable preventive activities. The potency of the new pyrimidines was increased when a difluoromethoxy or tetrafluorophenoxy group was introduced at the 4- or 3-position of the phenyl moiety and a methyl or ethyl group was introduced at the benzyl position. Structure–activity relationships are discussed. © 1998 Society of Chemical Industry 相似文献
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小麦条锈病、白粉病是发生于甘肃陇南乃至全国小麦生产上的最主要病害之一, 种植抗病品种是防治病害最经济有效且绿色环保的措施。兼抗种质资源材料的匮乏是制约甘肃陇南小麦条锈病和白粉病品种选育和病害有效防控的主要因素。农家品种是小麦抗病种质资源重要的基因库, 开展兼抗病害材料鉴定是准确评价供试材料抗病性的基础性工作。2021年和2022年, 在甘肃省农业科学院植物保护研究所兰州温室和甘谷试验站, 对127份小麦农家品种进行了苗期、成株期抗条锈病和白粉病性鉴定, 结果发现:供试材料中苗期对条锈菌和白粉菌混合菌表现抗病的分别有36份和24份, 占28.35%和18.90%;兼抗材料15份, 占11.81%。成株期在接种及自然诱发条锈菌和白粉菌条件下, 表现抗病的分别有39份和72份, 占30.71%和56.69%;兼抗材料有27份, 占21.26%。全生育期兼抗材料有11份, 占8.66%。抗白粉病基因分子检测结果发现, 含有抗病基因Pm2、Pm4a、Pm8、Pm21的分别占30.71%、86.61%、25.20%、3.15%;含有2个及以上基因组合品种有60个, 占47.24%。结合前期抗条锈病研究结果, 将会为筛选出的优异材料利用和持续解决甘肃陇南兼抗品种匮乏难题提供材料支撑。 相似文献
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R. Rabbinge I. T. M. Jorritsma J. Schans 《European journal of plant pathology / European Foundation for Plant Pathology》1985,91(5):235-247
Abastract The photosynthesis and transpiration rates of winter wheat leaves were measured at different developmental stages and at various levels of mildew infection. Even at low levels of infection, circa 4% leaf area being covered, both the assimilation and transpiration rates at light satiation were considerably reduced. Light use efficiency and dark respiration were not significantly affected. The physiological background of these effects was analysed by photosynthesis measurements at different external CO2 concentrations. It was shown that the carboxylation resistance was increased due to mildew infection and that stomatal resistance, boundary layer resistance and transport resistance in the mesophyll were only indirectly affected.A simulation model was used to compute the consequences of these effects on daily growth rate of a winter wheat canopy at different development stages and with different levels of mildew severity. These computations show that a low infection level may result in a considerable reduction of the crop growth rate. This effect was more pronounced when the sky was clear than overcast.Samenvatting Bepalingen van fotosynthese en verdamping werden verricht bij verschillende ontwikkelingsstadia van wintertarwe, die in verschillende mate was aangetast door meeldauw. Zelfs bij vrij lage infectiepercentages (circa 4%) was er al een aanzienlijke reductie van assimilatie en verdampingssnelheid bij lichtverzadiging. Lichtbenuttingsefficiëntie en donkerademhaling werden niet significant beïnvloed.De fysiologische achtergrond van deze effecten werd onderzocht door fotosynthesemetingen bij verschillende externe CO2 concentraties. Er werd aangetoond dat de carboxylatieweerstand werd verhoogd door meeldauwinfectie en dat de huidmondjesweerstand, grenslaagweerstand en transportweerstand in het mesofyl indirect werden beïnvloed.De gevolgen van deze effecten op de dagelijkse groeisnelheid van een wintertarwegewas in verschillende ontwikkelingsfasen en met verschillende LAI werd nagegaan met een simulatiemodel. Deze berekeningen tonen aan dat een geringe meeldauwaantasting resulteert in een aanzienlijke reductie van de groeisnelheid van het gewas. Dit effect was duidelijker bij heldere dan bij bewolkte hemel. 相似文献
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G. J. Niemann J. Dekker 《European journal of plant pathology / European Foundation for Plant Pathology》1966,72(3-6):213-221
Twenty-fivepara phenylenediamines and related compounds were tested for activity against powdery mildew on cucumber and against rust on bean. Some remarkable changes in activity resulted from minor changes in the chemical structure of the compounds. It is suggested that the fungicidal activity of the phenylenediamines is correlated with the polarographic halfwave potentials. This might indicate that one of the oxidation products, probably the semiquinone ion, is responsible for activity. 相似文献
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O. Ziv 《Phytoparasitica》1983,11(1):33-38
The effect of several epidermal coating polymers (antitranspirants) on two leaf diseases, Septoria leaf blotch and powdery mildew, was studied in wheat and barley, respectively. The commercial antitranspirants ‘Wilt Pruf’ and ‘Vapor Gard’ were the most effective polymers in controlling both diseases. 相似文献
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小麦白粉病反应型和产孢量的关系 总被引:1,自引:0,他引:1
利用小麦的6个品种及小麦白粉菌的3个小种研究了小麦苗期白粉病反应型与产孢量之间的关系。分别用累积单斑产孢量(LBSY)、累积单位面积产孢量(LASY)与反应型组建了反应型-产孢量关系模型:Y_1=exp(1.7178×lnX 0.0256X-2.484)(LBSY法);Y_2=exp(1.5168×lnX 0.052X-2.309)(LASY法)(X为反应型,Y为产孢系数)。通过LBSY方法获得反应型0,1,2,3~-,3,3~ ,4~-,4所对应的产孢系数分别为0,0.09,0.29,0.49,0.60,0.71,0.96,1。 相似文献
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种植模式、种植密度及施肥水平对小麦白粉病发生的影响 总被引:2,自引:0,他引:2
小麦白粉病是由布氏白粉菌Blumeria graminis (DC.) Speer.f.sp.tritici Marchal.引起的我国小麦生产上的重要病害。近年来,受品种、病原变异、气候、耕作制度及栽培条件等因素影响,其危害呈逐年加重的趋势,一般可减产5~10%,重病田减产20%以上,已成为制约小麦高产的重要因素[1]。研究表明,该病菌是一种专性寄生的子囊菌,分生孢子萌发温度范围为0.5~30 ℃,以10~20 ℃最适宜。小麦白粉病流行没有明显的周期性,一般中度或重度流行年后2~5年轻度流行。目前在我国广大小麦产区常采用含三唑酮成分的单剂或混剂进行防治,小麦白粉病菌产生了较为严重的抗药性。本试验在四川雅安小麦产区研究了小麦种植模式、密度及施肥水平对小麦白粉病发生及小麦产量的影响。 相似文献
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利用经初选确定的5种具有较好保鲜能力的配方,采用离体叶段滤纸保存法、离体叶段琼脂保存法和试管苗保存法对小麦白粉病菌纯化菌系保存效果进行了研究.结果表明,对小麦幼苗第一叶叶段保鲜效果最好的配方是沈保6号,当使用40~60μg/mL最适浓度时,第25天叶段绿色仍可达到90%以上.保存菌种的最适环境条件研究结果表明,在4℃冰箱中,以离体叶片沈保6号琼脂保存和离体叶沈保6号浸润滤纸保存效果最佳,在第40天叶片绿色仍分别达到78.0%和68.0%,孢子萌发率可达26.7%和26.8%. 相似文献
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R. A. Daamen I. T. M. Jorritsma 《European journal of plant pathology / European Foundation for Plant Pathology》1990,96(1):35-46
Wheat yield losses caused by powdery mildew were computed based on effects of the disease on leaf photosynthesis. Powdery mildew was introduced in a crop model of wheat by quantification of five parameters, taking the vertical and horizontal distribution of mildew in the crop into account. The most important parameters were those of the mildew intensity, the distribution of mildew in the crop, and the effect of mildew on assimilation at light saturation. Measured mildew epidemics in field experiments in three different years, were used to compute yield losses. Computed losses were compared to measured losses. On average, computed yield loss approached measured, but measured yield loss was underestimated, especially in early mildew epidemics due to the computation of partitioning and reallocation of assimilates. Other processes which may cause an underestimation are described. The use of crop models as a method to upgrade disease management systems is discussed.Samenvatting Opbrengstderving van wintertarwe werd berekend aan de hand van het effect dat meeldauw heeft op de blad-fotosynthese. Een rekenmodel voor de gewasgroei van tarwe werd uitgebreid met meeldauw. Met inachtneming van de vertikale en horizontale verdeling van meeldauw in het gewas, werd meeldauw in het model gekwantificeerd door vijf parameters. De belangrijkste parameters waren die van de meeldauwintensiteit, de verdeling van meeldauw in het gewas en het effect van meeldauw op de assimilatie bij een overvloed aan licht. Epidemieën van meeldauw, gemeten in veldproeven in drie verschillende jaren, werden gebruikt om opbrengstdervingen te berekenen. Gemiddeld kwam deze redelijk overeen met de in de veldproeven gemeten opbrengstderving. De gemeten opbrengstderving werd echter onderschat, vooral bij vroege epidemieën van meeldauw door de wijze waarop de (her)verdeling van assimilaten wordt berekend. Andere mechanismen, die een onderschatting van opbrengstderving kunnen veroorzaken worden besproken. Of deze modellen als methode gebruikt kunnen worden om systemen voor de geleide bestrijding van ziekten te verbeteren wordt bediscussieerd. 相似文献
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Infection by Erysiphe polygoni was followed on the components of five mixed populations containing different proportions of a partially resistant swede variety, Ruta Øtofte (RØ), and a highly susceptible variety, Ne Plus Ultra (NPU) (100:0; 75:25; 50:50; 25:75; 0:100). Disease levels remained much lower on RØ than on NPU in all populations. For several weeks, disease on NPU was greatest in pure plots and was progressively reduced in mixtures with increasing proportions of RØ. Later, disease levels on NPU were similar in all populations. Disease on RØ was not increased in mixtures with NPU. Root yield of NPU, but not of RØ, was greater in mixtures than in pure stands. The possible use of variety mixtures to control powdery mildew in swede crops is discussed. 相似文献