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水稻条纹叶枯病以其常发性和对水稻产量造成的巨大损失而越来越受到重视,许多省份已将其列为水稻生产上的第一大病害.笔者就水稻条纹叶枯病发病概况、抗病基因定位、抗性遗传研究以及抗病育种进行了综述,认为目前水稻抗条纹叶枯病研究中主要存在以下问题:在粳稻中缺乏高水平(免疫)抗源;分子遗传研究和抗病育种脱节以及抗性机理研究薄弱等.结合本课题组所进行的工作,认为当前水稻条纹叶枯病抗病遗传育种研究应着重于以下方面:继续筛选、创制粳稻抗源;应将聚合杂交育种和分子标记辅助选择结合应用,培育多基因抗病品种,同时展望了今后水稻条纹叶枯病的研究前景. 相似文献
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天津地区在20世纪80年代中期就有水稻条纹叶枯病零星发生。2000年以后该病逐年加重,2005年部分地区严重发生,病穴率30%~60%,稻谷减产10%~30%。目前其为害已超过稻瘟病和纹枯病,成为水稻的主要病害之一。前几年江苏省等南方地区粳稻条纹叶枯病大发生。我们学习南方的防治经验,在宁河县的防治实践中体会到,北方水稻条纹叶枯病的防治主要途径,是选用抗病品种和治虫防病。1选用抗病品种选用抗病品种是防治水稻条纹叶枯病最为经济有效的途径。天津及周边地区,抗条纹叶枯病的水稻品种比较多。津原45(W45)、津原47、津原17、中作52(中作9052)、… 相似文献
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水稻条纹叶枯病发生规律及防治技术研究进展 总被引:5,自引:0,他引:5
水稻条纹叶枯病自1990年以来在江苏省及其周边地区,呈逐年严重发生态势。就近年来水稻条纹叶枯病发生规律及防治技术研究进展进行了综述。 相似文献
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防治水稻条纹叶枯病的误区 总被引:2,自引:0,他引:2
水稻条纹叶枯病乃水稻生产大敌。近年江苏省因该病肆虐,造成水稻大面积减产。大敌当前,切不可掉以轻心。回顾近年水稻条纹叶枯病的防治工作,发现部分农户在防治上存在着六大误区。1选种不科学部分农户认为更换抗条纹叶枯病品种,就可以高枕无忧。殊不知,水稻条纹叶枯病是本省近几年才开始上升的新病害。由于我国针对该病害的抗性育种起步较晚,抗病品种的筛选和鉴定工作才刚刚起步,虽然生产上出现了一些抗性较好的品种,但抗性机理尚未完全明确,抗性稳定性有待考证。加之有些抗性品种综合抗性差(只抗条纹叶枯病,而高感其他病害,易倒伏等)或品质… 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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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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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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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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E. LIMPERT B. C. CLIFFORD A. DREISEITL R. JOHNSON K. MÜLLER A. ROELFS C. WELLINGS 《EPPO Bulletin》1994,24(1):109-112
A variety of systems of designation has evolved to name pathotypes of plant pathogens. The systems were evaluated to determine those best suited for particular purposes. Virulence and avirulence/virulence formulae of pathotypes have advantage over the use of consecutive numbers or letters given in chronological order of pathotype discovery. As soon as pathotype information exceeds a certain level of complexity, mathematical codes are most advantageous, in particular two codes, octal notation and coded triplets. A more universal adoption of the most appropriate codes is recommended to ease communication and comparisons of results. 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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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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