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玉米大斑病菌毒素对玉米叶肉细胞脂氧合酶活性的影响 总被引：1，自引：0，他引：1
玉米大斑病菌2号小种粗毒素(HT-C)和标准毒素(5-羟甲基-2-呋喃甲醛,HT-I)处理玉米叶片,都能诱导3种供试基因型玉米叶片中脂氧合酶活性增高,但是不同基因型玉米对HT-C和HT-I的反应不同,HT-I对含有Ht1基因的品系诱导时间早,水平高,HT-C对于不带Ht基因的品系LOX的影响略高于HT-I;不同浓度的HT-I在OH43和OH43Ht1玉米叶片中诱导的LOX酶活性不同,高浓度HT-I和HT-C对LOX酶活诱导时间早,水平高,浓度降低诱导水平降低;外源H2O2对HT-I和HT-C在OH43叶片中LOX酶活性诱导作用的影响不同。 相似文献
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玉米大斑菌Ht-毒素组分分析 总被引：11，自引：1，他引：11
对分别属于玉米大斑病菌(Helminthosporium turcicum)1号和2号生理小种的致病毒素进行硅胶TL层析、薄层扫描和生物监测的结果发现,两个小种的毒性组分不同。2号小种可分离到I(Rf0.50)、Ⅱ(Rf0.36)、Ⅲ(Rf0.67)、Ⅳ(Rf0.80)、Ⅴ(Rf0.13)、Ⅵ(Rf0.25)6种组分,而1号小种最多可分离到除Ⅳ以外的其它5种组分,这些组分均有不同程度的紫外吸收。对在200~360nm有明显紫外吸收的4种组分(Ⅰ、Ⅱ、Ⅲ、Ⅳ)的生物监测结果表明,只有组分Ⅲ对带Ht1基因和不带Ht1基因的Oh43和B372对玉米自交系不具任何致病活性,组分Ⅰ、Ⅱ对不带Ht1基因的玉米自交系具有致病活性,而对带Ht1基因的玉米自交系却无毒性。值得重视的是组分Ⅳ的致病特性与组分Ⅰ、Ⅱ正好相反,即对带Ht1基因的玉米自交系具有致病活性,却对不带Ht1基因的玉米自交系没有致病作用。结论指出,Ht-毒素的TLC组分Ⅰ、Ⅱ、Ⅳ玉米斑菌诱致玉米发病的主要活性成份,其中组分Ⅳ是2号小种与Ht1基因玉米互作的特异性因子。 相似文献
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玉米大斑病菌生理小种研究初报 总被引：14，自引：2，他引：12
1980年至1981年两年的试验结果表明:我国玉米大斑病菌存在着两个生理小种,即生理小种1号和生理小种2号。病菌标样采自辽宁、广西、浙江、陕西、黑龙江等地玉米大斑病菌共105个标样,病菌经分离培养接种在具有Ht1、,Ht2单基因抗性寄主以及多基因抗性寄主上。测定结果证明:接种在具有Ht1、Ht2单基因抗性寄主上表现为褪绿斑的菌株,属于生理小种1号,其毒力公式为Ht1Ht2/O (有效抗性基因/无效寄主基因)。接种在具Ht1单基因抗性寄主上表现有毒力产生萎蔫斑,而对Ht2鉴别寄主表现无毒力产生褪绿斑的菌株属于生理小种2号,其毒力公式为Ht2/Ht1。
目前玉米大斑病菌生理小种2号只在辽宁发现,尤以丹东地区出现频率较高。 相似文献
目前玉米大斑病菌生理小种2号只在辽宁发现,尤以丹东地区出现频率较高。 相似文献
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小麦抗条锈病已知基因对中国当前流行小种的有效性分析 总被引：1，自引：0，他引：1
小麦条锈病是危害我国小麦生产最为严重的病害之一,评价已知抗条锈病基因相对于当前主要流行小种的抗病性对开展预见性抗病育种工作具有重要的指导意义。本研究利用当前流行频率最高的2个小种(CYR32、CYR33)和1个对Yr26基因有毒性的新菌系V26/CM42对已知抗条锈病(Yr)基因的小麦材料分别进行苗期小种抗病性鉴定和成株期病圃抗病性调查,以评估各已知Yr基因在中国抗病育种中的有效性。结果表明,只有3个Yr基因(Yr5、Yr15和Yr61)对当前流行小种和贵22新菌系表现为全生育期抗病性;3个Yr基因(Yr32、YrTr1和YrTye)具有成株期抗病性;此外,Mega、Ibis、Hyak、Maris Huntsman、Hobbit、CarstensV、Express、Lee和Compair等9个含多个Yr基因组合的抗源品种表现出良好的成株期抗条锈性。 相似文献
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采用我国当前流行的小麦条锈菌小种和重要致病类型, 在常温条件下对普通小麦-华山新麦草易位系H9015-17进行苗期抗条锈性鉴定, 并用当前主要流行小种CYR32对H9015-17与铭贤169的杂交后代及其双亲进行抗条锈性遗传分析, 以揭示H9015-17抗条锈性遗传基础。结果显示, H9015-17对小麦条锈菌小种CYR31、CYR32、CYR33和致病类型Su11-4、Su11-7、V26、Su11-11均有良好的抗病性, 对当前主要流行小种CYR32的抗病性由1对显性基因控制, 暂命名为YrHua1。 采用分子标记定位技术,筛选到5个与抗病基因YrHua1连锁的RGAP标记(M1、M2、M3、M4和M5)和1个SSR标记(Xgwm292),这些标记与抗病基因YrHua1的遗传距离分别为17.3、15.7、13.1、3.3、2.9和11.2,并将基因YrHua1定位在小麦染色体5DL上。研究结果将为分子标记辅助选择改良小麦抗条锈性提供宝贵的种质材料,建议在抗病育种加以利用。 相似文献
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中国玉米大斑病菌生理分化及新命名法的初步研究 总被引：27，自引：0，他引：27
在分别含Ht1、Ht2、Ht3和HtN的单基因玉米鉴别寄主上测定了全国玉米各产区的百余份大斑病菌标样。结果表明,按传统方法命名的1号(或称0号)生理小种仍然是优势小种,占供试菌株的73.0%;2号(1号)生理小种占1.9%。虽然未出现已报道的3号(23号)、4号(23N号)和5号(2N号)小种,但特别值得注意的是出现了25.1%的未定名的新类群。为克服传统命名方法的局限性及指导抗病育种及品种布局,本文初步提出用毒力频率法分析玉米大斑病菌的生理分化状况,并进一步指明了不同致病类群在我国的分布频率及Ht基因的可用范围。 相似文献
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香蕉假茎细胞对枯萎病菌不同小种及其粗毒素的病理反应 总被引：17，自引：0，他引：17
以香蕉枯萎病菌(Fusarium oxysporum f.sp.cubense)1号小种和4号小种及其粗毒素分别接种香牙蕉和粉蕉的组培苗及离体假茎后,用组织切片法观察香蕉假茎细胞的病理反应,以探明香蕉枯萎病菌不同小种及其粗毒素的致病作用。结果表明,枯萎病菌不同小种人工接种仅能感染相应的香蕉种类,但不同香蕉种类的离体假茎细胞用不同小种接种及其粗毒素处理,均产生褐变等病理反应,且病变程度不存在小种间的差异。表明枯萎病菌不同小种对香蕉不同种类的致病力差异可能与存在其它致病因子或专化性识别的因子有关。同时证实了病菌不同小种的毒素对蕉类不存在着选择毒性 相似文献
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N. Strampelli是由意大利引入我国的小麦持久抗病性品种,对我国目前多数的条锈菌流行小种均有良好的抗性。为了明确其抗条锈病基因的遗传机制,利用小麦条锈病小种CYR30、CYR31、Su-4和Su-14对N. Strampelli与中国春杂交后代进行遗传分析,结果表明N. Strampelli对CYR30、CYR31的抗病性均由1对显性基因和1对隐性基因互补控制,对Su-14、Su-4的抗病性各由1对隐性基因控制,将其中控制Su-14抗病性的隐性基因暂时命名为YrNS-1。利用分离群体分析法(BSA)对接种Su-14的正交F2代群体进行SSR分子标记,在1BL上找到4个与YrNS-1紧密连锁的微卫星标记Xwmc719、Xgwm124、Xwmc44和Xcfa2147,遗传距离分别为3.2、4.6、5.7和10.3cM。与已知位于1BL染色体上的抗条锈基因比较分析表明,YrNS-1可能是1个新的抗条锈病基因。 相似文献
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陕西省115个小麦品种(系)抗条锈病基因的分子检测 总被引：3，自引：0，他引：3
为掌握陕西省主栽与后备小麦品种对我国条锈菌的抗性水平,明确其抗锈基因分布,本研究选用条锈菌流行小种CYR32和新毒性小种V26对115份陕西省主栽和后备小麦品种(系)进行苗期抗病性鉴定,并分别利用抗条锈病基因Yr5、Yr9(1B/1R)、Yr10、Yr18和Yr26的紧密连锁分子标记对这115份材料进行了分子检测。结果表明,供试小麦品种(系)中,抗CYR32的有61份,占53.04%;抗V26的有84份,占73.04%;对2个小种均抗病的有50份,占43.48%。分子检测发现115份材料均不含有Yr10;可能携带Yr9基因的有41份,占35.65%;可能含有Yr5、Yr18和Yr26的材料分别为3份、3份和2份,占2.61%、2.61%和1.74%。因此,当前陕西省主栽与后备小麦品种(系)对CYR32和V26的抗性整体水平还有待进一步提高,Yr9分布频率较高,而Yr5、Yr10、Yr18和Yr26分布频率较低,建议在以后小麦育种中减少Yr9的使用,加强利用Yr5和Yr18与其他有效基因聚合培育持久抗条锈病品种。 相似文献
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福寿螺配偶个体大小选择性初步观察 总被引：7，自引：0，他引：7
通过野外观察与实验研究,掌握了福寿螺的婚配体制及其配偶选择性规律。福寿螺与多数低等动物一样,其婚配属于乱交制,无固定配偶;雌螺对与其交配的雄螺个体大小没有选择性,而雄螺对雌螺的个体大小有选择性,倾向于与较大个的雌螺交配。 相似文献
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F.M. Ashton O.T. de Villiers R.K. Glenn W.B. Duke 《Pesticide biochemistry and physiology》1977,7(2):122-141
Time- and concentration-course studies were conducted to determine the effect of thirteen herbicides on photosynthesis, respiration, RNA synthesis, protein synthesis, and lipid synthesis using isolated single leaf cells. Each herbicide was from a different chemical class. Appropriate 14C-substrates and product purification procedures were used for each process prior to liquid scintillation counting. The most sensitive metabolic site of inhibition was photosynthesis for atrazine, bromacil, dichlobenil, monuron, and paraquat; RNA synthesis for dalapon and dinoseb; protein synthesis for chlorpropham; and lipid synthesis for CDAA, chloramben, 2,4-D, EPTC, and trifluralin. However, with several herbicides, one or more process was almost as sensitive as the one mentioned above. All herbicides inhibited more than one process, and the most sensitive site of inhibition may not be the same process that was inhibited the greatest at the maximum concentration and maximum exposure time used. Therefore, a concept of metabolic sites of action, rather than a primary site of action, appears to be more meaningful for herbicides. 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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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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Magdalina I. Luzhnova Lyudmila M. Shekhtman 《Pesticide biochemistry and physiology》1975,5(3):205-210
The effect of meturine on the light processes of photosynthesis was studied.Meturine is a herbicide for weed control in potato and cotton crops. It is a N-phenyl—N-hydroxy—N′-methylurea.The experiments were carried out on isolated pea and spinach chloroplasts.When examining photosystem I, reduced DPIP was used as an electron donor, whereas methyl-viologen served as an electron acceptor. When examining photosystem II, DPIP represented the electron acceptor.The obtained experimental results have pointed to the absence of the effect of meturine upon the photoreaction I.Unlike N-phenyl—N′, N′-dimethylureas (CMU, DCMU) meturine has been a very weak inhibitor of photoreaction II.The authors explain the photoreaction II inhibition of chloroplasts from plants treated with herbicidal doses of meturine by conversion of N-phenyl—N-hydroxy—N′-methylurea into Hill reaction inhibitor(s). N-Phenyl—N′-methylurea can be one of such meturine metabolites.Meturine herbicidal action is accounted for by meturine transformation into Hill reaction inhibitor(s) in the plant tissues. 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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ABSTRACT Conventional models for the durability of resistant cultivars focus on the dynamics of the frequency of resistance genes. This leads to a definition of the durability of resistance as the time from introduction of the cultivar to the time when the frequency of the virulence gene reaches a preset threshold. It is questionable whether this is the most appropriate way to measure durability. Here we use a simple epidemiological model to link population dynamics and population genetics to compare three measures of durability: (i) the expected time until invasion of the virulent genotype, by mutation or immigration, and subsequent establishment of a population (T(invasion)); (ii) the virulence frequency related measure of the time for the virulent genotype to take-over the pathogen population ( T(take-over)); and (iii) the additional yield, measured by the additional number of uninfected host growth days (T(additional)). Specifically, we show how the measures of durability are affected by deployment and epidemiological parameters. We use a combination of numerical solution and analytical approximation of a model for the population dynamics of avirulent and virulent genotypes of a pathogen growing in dynamically changing populations of resistant and susceptible cultivars. The three measures of durability are compared. Some consequences of the results for durable resistance in multilines and mixtures and the regional deployment of resistant cultivars are discussed. 相似文献
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