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为了解致病类型G22-83及流行小种CYR32和CYR33对四川省近年小麦生产品种和后备品种的寄生适合度,在田间分别将致病类型G22-83、流行小种CYR32和CYR33接种于四川省109个小麦品种(系),采用综合病情指数法测定3个供试菌株的相对寄生适合度。结果显示,致病类型G22-83、流行小种CYR32和CYR33的平均寄生适合度分别为0.1930、0.0560和0.0379,且前者显著高于后两者;流行小种CYR32和CYR33的平均相对寄生适合度有差异,但是差异不显著。致病类型G22-83、流行小种CYR32和CYR33在四川省109个小麦品种(系)上相对寄生适合度的中位数分别为0.0626、0.0000和0.0000,前者在四川省109个小麦品种(系)上相对寄生适合度的平均水平和波动程度均高于后两者。致病类型G22-83在四川省小麦生产品种和后备品种上的寄生适合度较高,在今后一段时间内可能成为该地区小麦条锈菌的优势菌系。 相似文献
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云南马铃薯晚疫病菌生理小种的研究 总被引：13，自引：1，他引：13
从采自云南省5个地州12个县市的马铃薯晚疫病标本上分离纯化出152个分离物 ,按马铃薯种植面积的多少每地选取代表性菌株41个 ,供作马铃薯晚疫病菌生理小种鉴定。用离体叶片测定法和Black等生理小种与鉴别寄主基因型关系表 ,确定其生理小种。鉴定结果表明 ,云南省马铃薯晚疫病菌生理小种有4种类型 ,为0号、3号、4号和3,4号小种 ,其中3号小种占所测菌株的39.02% ,分布在丽江等8个县市;0号小种占31.70% ,分布在昭通等8个县市;3,4号小种占21.95% ,分布在昆明等3个县市;4号小种占9.75% ,分布在昆明地区 相似文献
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为明确宁夏回族自治区马铃薯主产区晚疫病菌的交配型种类以及生理小种的类型、组成和分布,为宁夏有针对性地选育马铃薯抗晚疫病品种提供科学依据。利用A1、A2交配型标准菌株和含有11个主效抗性基因的鉴别寄主,对2018年-2019年从原州区、泾源县、彭阳县、隆德县、西吉县、盐池县、海原县采集得到的130个马铃薯晚疫病菌菌株进行交配型和生理小种鉴定。结果表明,宁夏马铃薯晚疫病菌群体的交配型和生理小种存在多样性,采集地交配型有A1、A2、SF(自育型)3类,分别占被测菌株的30%、63.8%、6.2%;生理小种有8种类型,其中生理小种1.2.3.4.5.6.7.8.9.10.11发生频率最高,占被测菌株总数的44.62%,是宁夏马铃薯主栽区的晚疫病菌优势小种,在各测试地均有分布;次优势小种为3.4.10和1.2.3.5.6.7.8.11,发生频率分别为12.31%和10.77%。宁夏不同种植区域马铃薯晚疫病菌交配型组成复杂,采集地组成差异较大,但西吉县、原州区交配型年度间的变化基本趋于一致。宁夏马铃薯晚疫病菌群体组成日趋复杂,生产中要合理布局已有抗病品种,挖掘培育抗病水平高的新品种,综合防控马铃薯... 相似文献
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黑龙江省马铃薯晚疫病菌交配型及对甲霜灵敏感性测定 总被引：1，自引：0，他引：1
马铃薯晚疫病(late blight)是由致病疫霉(Phytophthora infestans)引起的马铃薯生产中最具毁灭性的病害,明确晚疫病菌的交配型及对甲霜灵敏感性状况对制定马铃薯晚疫病防治策略具有重要意义。本研究对2011—2013年采自黑龙江省黑河、齐齐哈尔、绥化等马铃薯主产区的晚疫病菌菌株进行交配型及对甲霜灵敏感性测定,采用对峙培养法对153株晚疫病菌进行交配型检测,结果表明,A1交配型79株,占51.63%,A2交配型74株,占48.37%;采用菌落直径法对143株晚疫病菌进行甲霜灵敏感性测定,结果表明,83.92%表现高抗,8.39%表现中抗,7.69%表现敏感。 相似文献
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植物病原菌寄生适合度测定方法的研究（以小麦条锈菌为例） 总被引：15，自引：6，他引：9
在多品种-多小种系统的群体动态研究中,各小种在各品种上的相对寄生适合度的测定是一个关键问题。根据推理论证和模拟试验,作者认为:采用相对r值作为寄生适合度的量化指标是合理可行的。相对r值可以采用分小种方块圃法或根据田间病情进行直接测定,也可采用分小种短行圃法进行间接测定,即根据流行组分观察数据或反应型、普遍率、严重度和潜育期的记载,通过模型模拟推算出相对寄生适合度。间接测定较易操作,但它要求有一个相当可靠的流行模拟模型,并在模拟中选用适当的环境条件。根据反应型、普遍率、严重度和潜育期推算和模拟寄生适合度,是较最简便的间接测定方法,此法可利用品种抗病性分小种鉴定的数据来推算寄生适合度。 相似文献
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在多品种－多小种系统的群体动态研究中，各小种在各品种上的相对寄生适合度的测定是一个关键问题。根据推理论证和模拟试验，作者认为：采用相对ｒ值作为寄生适合度的量化指标是合理可行的。相对ｒ值可以采用分小种方块圃法或根据田间病情进行直接测定，也可采用分小种短行圃法进行间接测定，即根据流行组分观察数据或反应型、普遍率、严重度和潜育期的记载，通过模型模拟推算出相对寄生适合度。间接测定较易操作，但它要求有一个相当可靠的流行模拟模型，并在模拟中选用适当的环境条件。根据反应型、普遍率、严重度和潜育期推算和模拟寄生适合度，是较最简便的间接测定方法，此法可利用品种抗病性分小种鉴定的数据来推算寄生适合度。 相似文献
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Christopher D. Keating Lindy M. Holden-Dye Robert J. Walker 《Pest management science》1996,46(3):263-266
The neuropeptide AF2 has a complex set of actions on the dorsal muscle strip of Ascaris suum, including a potentiation of the acetylcholine-stimulated muscle contraction. Caffeine at 100 μm and 5 mm inhibited this potentiation, as did 100 μm theophylline in two out of six studies. The cyclic-AMP-potentiating compounds IBMX, dibutyryl cAMP and forskolin had no effect on the AF2-induced potentiation of the acetylcholine-stimulated muscle contraction. These preliminary data suggest that the potentiating action of AF2 is not mediated by a cAMP pathway. 相似文献
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Effects of timing and method of application of Penicillium oxalicum on efficacy and duration of control of Fusarium wilt of tomato 总被引：3，自引：0，他引：3
The effects of timing and method of application of Penicillium oxalicum on the control of fusarium wilt of tomato were investigated. Application of P. oxalicum to tomato seedlings in seedbeds reduced disease caused by Fusarium oxysporum f.sp. lycopersici in a growth chamber by 45–49% and in glasshouse experiments by 22–69%. Disease suppression was maintained for 60–100 days after inoculation with the pathogen in the glasshouse. No disease reduction was observed in tomato plants where P. oxalicum was applied to seeds. Treatment with P. oxalicum did not affect the population of F. oxysporum f.sp. lycopersici in the rhizosphere. 相似文献
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棉花黄萎病菌致病型的AFLP分析 总被引：16，自引：0，他引：16
选用41个棉花黄萎病菌(Verticillium dahliae)代表菌系,在温室条件下,对4个棉花品种鄂荆1号(感)、中棉所12(耐)、文-5(抗)和唐棉2号(抗)进行致病性测定,结果可将供试菌系分为落叶型与非落叶型2类。选取8对AFLP引物PCR扩增的结果中,统计带型稳定、清晰且有多态性的条带,共169条作系统聚类分析,将上述菌系分为2大类,第一类为非落叶型菌系,包括10个非落叶型菌系和1个过渡菌系;第二类为30个落叶型菌系。根据聚类分析建立树状图,发现菌系与地理来源存在一定的相关性,而依据菌系致病力强弱分类则相关关系不大。选用25对EcoRⅠ和MseⅠ引物组合,对供试的41个V.dahliae进行AFLP扩增,筛选到2对引物E64(GACTGCGTACCAATTCGAC)、M53(GATGAGTCCTGAGTAACCG)和E49(GACTGCGTACCAATTCCAG)、M65(GAT-GAGTCCTGAGTAAGAG),能分别扩增出433bp和110bp2条仅为V.dahliae非落叶型菌系独有的特异片段,可将落叶型与非落叶型菌系分开,这2条特异片段被命名为EM433和EM110。 相似文献
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The mode of action of the 2,4-diphenyl-1,3-oxazoline acaricide/insecticide etoxazole has been argued to be moulting inhibition, but experimental results supporting this hypothesis are lacking. This study investigated the effect of etoxazole on chitin biosynthesis in the fall armyworm, Spodoptera frugiperda (Smith) (Lepidoptera: Noctuidae). Etoxazole induced moulting defects in fall armyworm larvae similar, if not identical, to those caused by benzoylphenylureas, a well-known class of insecticidal chitin biosynthesis inhibitors. Furthermore, in contrast to untreated larvae, the chitin content in the integuments of larvae several days after treatment did not differ from that in freshly ecdysed individuals, thus suggesting strong chitin biosynthesis inhibition in vivo. A more detailed investigation of the inhibitory potential by incubating cultured integument pieces from larvae of S. frugiperda with [14C]N-acetyl-D-glucosamine, a radiolabelled chitin precursor, revealed I50 values of 2.95 and 0.071 microM for etoxazole and triflumuron respectively. The incorporation of radiolabel into potassium hydroxide-resistant material was inhibited by etoxazole in a dose-dependent manner. Based on these results, it is concluded that the acaricidal and insecticidal mode of action of etoxazole is chitin biosynthesis inhibition. 相似文献
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为了研究青稞种子外部和内部携带真菌情况,比较不同杀菌剂对青稞种子的带菌消毒效果和对幼苗生长的影响,为青稞种子播前包衣处理和种传真菌病害防控提供依据,采用离体平皿法对云南迪庆‘云青1号’、‘云青2号’和‘短白青稞’3个主栽品种进行带菌检测,并对种子进行拌种或浸种处理测定6种杀菌剂对种子消毒效果,分析杀菌剂对种子发芽和幼苗生长的影响。结果表明:供试青稞种子表面携带的优势菌群为青霉(Penicilliumspp.)、镰刀菌(Fusariumspp.);种子内部寄藏的真菌主要为镰刀菌、核腔菌(Pyrenophoraspp.)、附球菌(Epicoccumspp.)、丝核菌(Rhizoctoniaspp.)、链格孢(Alternariaspp.)和木霉(Trichoderma spp.)。青稞不同品种的种子表面及内部携带的真菌种类差异较大。致病性测定表明,镰刀菌对种子萌发和幼苗生长影响最大,后期出现幼苗坏死现象。45%咪鲜胺EW、75%百菌清WP、50%福美双WP对青稞种子携带真菌均有显著抑制作用和消毒效果,50%福美双WP消毒效果最优,达100%;45%咪鲜胺EW、75%百菌清WP、50%福美双WP处理对青稞种子发芽和幼苗生长均无显著影响。 相似文献
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调查了甘肃省临洮县为害百合的地下害虫种类, 并以主要发生为害种类为供试对象, 采用拌土法测定了几种生物（源）农药对主要害虫的室内毒力和致死中时。调查发现小云斑鳃金龟Polyphylla gracilicornis、棕色鳃金龟Holotrichia titanis为主要发生及为害种类, 不同时间发生种类存在差异, 9月份以小云斑鳃金龟幼虫发生为害为主, 发生量占地下害虫总数的66.16%, 平均种群密度为10.48头/m2, 10月份, 则以棕色鳃金龟幼虫发生为主, 发生量占地下害虫总数的96.86%, 平均种群密度为7.79头/m2, 主要取食百合根系和鳞茎, 造成根系数量减少, 鳞茎出现不规则褐色缺口或凹陷斑。药剂筛选结果表明, 1.8%阿维菌素乳油、200亿孢子/g球孢白僵菌粉剂对两种蛴螬均具有较高的杀虫活性和速效性, 药后7 d时, 校正死亡率在82.22%以上, 对小云斑鳃金龟幼虫和棕色鳃金龟幼虫的LC50分别为0.161、0.060 mg/g和5.558×107、0.362×107孢子/g, LT50分别为2.237 d（2.2 mg/g）、1.393 d（2.2 mg/g）和6.645 d（40.0×107孢子/g）、4.940 d（2.0×107孢子/g）, 这两种生物（源）农药对两种蛴螬的LC50和LT50值均略大于两种化学农药25%二嗪磷乳油、40%辛硫磷乳油处理的, 且对小云斑鳃金龟幼虫的杀虫活性均低于对棕色鳃金龟幼虫的杀虫活性, 致死中时则长于对棕色鳃金龟幼虫的致死中时。 相似文献
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Sj J. Gerbrandy 《European journal of plant pathology / European Foundation for Plant Pathology》1992,98(5):269-276
The variability of dormancy of sclerotia of ten isolates ofSclerotium cepivorum was investigated. Of all isolates tested, the freshly harvested sclerotia were dormant. After drying for 48 hours the sclerotia of six isolates were able to germinate, two isolates stayed dormant and two isolates were infested by hyperparasitic fungi. After storage in soil at 5°C or 20°C, the sclerotia of the different isolates exhibited considerable differences in respect to germination capability, but all isolates showed highest germination after a treatment of 8 weeks at 20°C followed by 8 weeks at 5°C. The sclerotia of all isolates showed an increased capacity to germinate withoutAllium extracts at 10°C after pretreatment at 30°C for 28 days. 相似文献
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Zahida Iqbal Syuntaro Hiradate Akio Noda Sei-Ichi Isojima Yoshiharu Fujii 《Weed Biology and Management》2002,2(2):110-115
The allelopathic potential of buckwheat ( Fagopyrum esculentum ) was investigated. Field study showed that living buckwheat reduced weed biomass compared with plots without buckwheat. Laboratory study revealed that root exudates suppressed root and shoot growth of weeds and reduced weed dry weight. Sequential partitioning of the aqueous ethanolic extract of the aerial parts of buckwheat showed that the chloroform extract caused an 80% reduction in radicle elongation of lettuce seedlings at a concentration of less than 100 p.p.m. Fagomine, 4-piperidone and 2-piperidinemethanol were isolated and identified by 1 H and 13 C nuclear magnetic resonance from the chloroform extract. These compounds caused a 50% inhibition of radicle elongation in lettuce seedlings at concentrations of less than 100 p.p.m. These results suggest that compounds 1, 2, and 3 might act as allelochemicals and affect the growth or germination of different plant species. 相似文献