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《河南职业技术师范学院学报(职业教育版)》2016,(1)
2013—2015年从河南新乡地区5个县市采集玉米小斑病标样,对分离出的413个玉米小斑病菌菌株进行了生理小种鉴定和群体结构分析.结果表明:新乡地区玉米小斑病菌有T、C、S、O等4种生理小种.其中,O小种的分离频率最高,是新乡地区玉米小斑病菌的优势小种,分离频率为56.1%;其次是S小种和T小种;C小种的出现频率最低,分离频率仅为5.1%.群体结构分析表明,在2013—2015年不同小种的数量在年度间动态变化规律有所差异:O小种群体数量逐渐减少;T小种和S小种群体数量逐年增加;C小种群体数量基本保持稳定.新乡地区玉米小斑病菌优势小种O小种具有不同的致病能力,强致病力菌株出现频率为23.36%,中致病力菌株出现频率为37.98%,弱致病力菌株出现频率为38.66%. 相似文献
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利用荧光光谱法、紫外吸收光谱法、同步荧光法和三维荧光法研究了金属离子Fe2＋、Fe3＋与牛血清白蛋白（BSA）在模拟生理条件下的竞争结合作用.结果表明,Fe2＋、Fe3＋对BSA的内源荧光都有明显的猝灭作用,猝灭机理均为静态猝灭和动态猝灭的联合作用,主导作用分别为静态猝灭和动态猝灭,并分别计算了结合常数、结合位点数和热力学参数,Fe3＋与BSA的结合能力强于Fe2＋.弱的结合力使BSA与Fe2＋、Fe3＋相互作用后构型没有明显改变.当Fe2＋、Fe3＋同时与BSA相互作用时,二者表现出弱的竞争取代现象. 相似文献
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用已筛选的3种寡聚糖激发子A1、B、C3分别诱导毛白杨愈伤组织,以加无菌水为对照,并在诱导48 h后挑战接种杨树溃疡病菌,测定毛白杨愈伤组织中苯丙氨酸解氨酶、几丁质酶和抗坏血酸氧化酶活性的变化。结果表明,3种寡聚糖激发子A1、B、C3诱导48 h后接种杨树溃疡病菌,毛白杨愈伤组织中苯丙氨酸解氨酶和几丁质酶活性均呈单峰曲线变化,并且变化趋势基本上满足:A1>B>C3>CK(对照接种),而抗坏血酸氧化酶活性的变化为:在发病初期和中期(0-48 h)诱导接种毛白杨愈伤组织均高于对照接种,而在发病后期(t>48 h)对照接种毛白杨愈伤组织高于诱导接种,因此,可以得出寡聚糖激发子A1的诱导抗病性比寡聚糖激发子B和C3都强。 相似文献
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采用活体接种的方法,比较致病疫霉在辣椒和番茄上的致病性差异;结果表明致病疫霉在两种寄主上都能侵染,但是在番茄上的致病能力远远强与辣椒上的致病能力. 相似文献
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为了检验狐米草低能重离子各诱变株系在表型、生物量和内部生理生化状态发生变化的同时,其遗传物质DNA是否发生改变,试验检测了狐米草对照株系与各诱变株系的ITS序列.结果发现,所检测的狐米草10个诱变株系的ITS序列与对照株系完全一致,仅与美国德克萨斯州和路易斯安那州的狐米草株系差别1-2个碱基,显示低能重离子束诱变并没有导致狐米草株系在ITS区段发生变异. 相似文献
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抗CMV病毒外壳蛋白CP基因导入黄瓜的研究 总被引：3，自引：0，他引：3
将CMV-CP基因经农杆菌感染介导转化黄瓜子叶,将CMV-CP基因导入黄瓜细胞,在含有卡那霉素和羧卡青霉素的MS培养基上诱导子叶分化,获得一批转化处理的黄瓜再生苗,分化率为23%左右,转基因黄瓜试管苗移栽在蔬菜种植土沙有机质为541的混合土中,其移栽成活率可达56%;委托省农科院品种引进中心进行转基因黄瓜再生植株对CMV的抗性接种试验结果表明7号株系为高抗,2、4号株系为中抗. 相似文献
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利用不同浓度的镰刀菌粗毒素和水杨酸溶液处理供试大豆,观察粗毒素和水杨酸溶液对大豆种子萌发、生长情况及对大豆根腐病的诱导抗病性研究.结果表明:经镰刀菌毒素处理的大豆,随着处理浓度的升高,萌发率下降了10%.将镰刀菌毒素和水杨酸溶液接种于大豆植株进行盆栽试验,诱导其对大豆根腐病菌的抗性,试验结果表明:经镰刀菌毒素处理的大豆植株,对根腐病菌的抗性比对照提高了10%,而经水杨酸溶液处理的大豆植株,对根腐病菌的抗性比对照提高了5%左右.筛选出广谱、高效、无毒的诱导抗病剂,并应用于大豆根腐病的防治将成为植物病害防治的一种新途径. 相似文献
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近20年来,人们对3,4-二甲基-2-苯基-1,4-氧氮杂-5,7-二酮（Ⅰ）这一重要手性化合物进行了大量研究工作,利用它的手性诱导作用合成了许多高光产率的化合物,这其中包括生物碱及抗白血病药物．随着不对称合成全盛的发展,对（Ⅰ）合成生物活性的化合物前景看好． 相似文献
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Liu XIE Jing-ze ZHANG Yao WAN Deng-wei HU 《Journal of Zhejiang University. Science. B》2010,11(1):61-70
Strawberry anthracnose, caused by Colletotrichum spp., is a major disease of cultivated strawberry. This study identifies 31 isolates of Colletotrichum spp. which cause strawberry anthracnose in Zhejiang Province and Shanghai City, China. Eleven isolates were identified as C. acutatum, 10 as C. gloeosporioides and 10 as C. fragariae based on morphological characteristics, phylogenetic and sequence analyses. Species-specific polymerase chain reaction (PCR) and enzyme digestion further confirmed the identific... 相似文献
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近年来,在连云港前三岛发现一数量极多、危害严重的“吸血蝇”。经鉴定为厩螫蝇Stomoxys calcitrans(Linnaeus,1758).属蝇科Muscidae、螫蝇属Stomoxys Geoffroy.据文献记载,该蝇不仅吸食人、畜血液,还会传播炭疽病等多种传染病。本文在综述的基础上将对其生活习性、分布、生活史等做进一步研究,旨在提出防治和控制措施。 相似文献
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为明确脐橙炭疽病的病原,本研究调查江西赣南地区的脐橙园炭疽病流行情况,采集病症突出的叶片和果实,在实验室进行分离鉴定得致病菌纯培养.对其进行形态学和菌落特征鉴定,测定其生物学特性和生理生化特性.试验结果表明脐橙炭疽病为胶孢炭疽菌Colletotrichum.gloeosporioides(penz.)sacc.在PDA上,菌丝生长和孢子萌发的适温为23℃-28℃.最适pH为6.0.能利用多种碳源和氮源,其中葡萄糖是最佳碳源,硝酸钾是最佳氮源. 相似文献
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目的 :观察泌尿生殖道感染病原菌临床分布特点及耐药性方法 :采集 10 3例男性患者尿道分泌物标本 ,分离培养同时检测各菌株药物敏感性结果 :共分离出凝固酶阳性葡萄球菌 (CNS) 5 0株 ,肠球菌 31株 ,金黄色葡萄球菌 9株 ,棒状杆菌 10株 ,真菌 3株 .耐药率较高 5种抗生素为 :青霉素G ,苯唑青霉素 ,先锋V ,环丙沙星 ,阿奇霉素 ;未发现耐万古霉素 ,丁胺卡那菌株。结论 :葡萄球菌是泌尿生殖道感染中最重要的病原体之一。 相似文献
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Young Soo Kim Kotnala Balaraju Yongho Jeon 《Journal of Zhejiang University. Science. B》2016,17(12):931-940
In this study, plant growth-promoting rhizobacteria (PGPR) were evaluated as potential biocontrol agents against postharvest pathogens of apple fruits. In vitro bioassays revealed that, out of 30 isolates screened, isolates APEC136 and APEC170 had the most significant inhibitory effects against the mycelial growth of several fungal pathogens. Analysis of 16S ribosomal RNA (rRNA) sequences identified the two effective isolates as Paenibacillus polymyxa and Bacillus subtilis, respectively. The two strains showed greater growth in brain-heart infusion broth than in other growth media. Treatment of harvested apples with suspensions of either strain reduced the symptoms of anthracnose disease caused by two fungal pathogens, Colletotrichum gloeosporioides and Colletotrichum acutatum, and white rot disease caused by Botryosphaeria dothidea. Increased productions of amylase and protease by APEC136, and increased productions of chitinase, amylase, and protease by APEC170 might have been responsible for inhibiting mycelial growth. The isolates caused a greater reduction in the growth of white rot than of anthracnose. These results indicate that the isolates APEC136 and APEC170 are promising agents for the biocontrol of anthracnose and white rot diseases in apples after harvest, and suggest that these isolates may be useful in controlling these diseases under field conditions. 相似文献
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Po Po THAN Haryudian PRIHASTUTI Sitthisack PHOULIVONG Paul W.J. TAYLOR Kevin D. HYDE 《Journal of Zhejiang University. Science. B》2008,9(10)
Anthracnose disease is one of the major economic constraints to chilli production worldwide, especially in tropical and subtropical regions. Accurate taxonomic information is necessary for effective disease control management. In the Colletotrichum patho-system, different Colletotrichum species can be associated with anthracnose of the same host. Little information is known concerning the interactions of the species associated with the chilli anthracnose although several Colletotrichum species have been reported as causal agents of chilli anthracnose disease worldwide. The ambiguous taxonomic status of Colletotrichum species has resulted in inaccurate identification which may cause practical problems in plant breeding and disease management. Although the management and control of anthracnose disease are still being extensively researched, commercial eultivars of Capsicum annuum that are resistant to the pathogens that cause chilli anthracnose have not yet been developed. This paper reviews the causal agents of chilli anthracnose, the disease cycle, conventional methods in identification of the pathogen and molecular approaches that have been used for the identification of Colletotrichum species. Pathogenetic variation and population structure of the causal agents of chilli anthracnose along with the current taxonomic status of Colletotrichum species are discussed. Future developments leading to the disease management strategies are suggested. 相似文献
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O. Roger Anderson 《科学教学研究杂志》1969,6(3):265-273
This paper combines biological, biochemical and psychological data toward the construction of a bio-psychological theory of behavior. The fundamental assumptions are that the environment favored the evolution of organisms possessing receptors sensitive to periodic or repetitive stimuli. Moreover the presence of periodic stimuli in space and time have induced, through natural selection, the appearance of highly advanced forms of living organisms capable of exploiting the environment by utilizing information in periodic stimuli. Indeed, this dependency on periodic stimulation, such as light energy and movement of surrounding matter, has induced a psychological, perceptual bias to readily assimilate repetitive stimuli thereby producing changes in behavior. This perceptual bias favored by organic evolution and reinforced by stimulation of the organism during development produces communication patterns in higher animals characterized by repetitive sounds. The relationship of this theory to current learning models is discussed and applications are made to human learning. 相似文献
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城市绿地群落构建现存问题与优化 总被引：6，自引：0，他引：6
本文分析了目前城市绿地群落构建中存在的问题，讨论了绿地群落的特征和合理结构，并探讨了基于生物多样性的城市绿地群落构建途径。即开发以地带性物种为核心的多样化绿化植物品种，培育苗木产业；模拟地带性群落的结构特征，遵从“生态位”原则，构建乔灌草复层群落结构；适当恢复和重建城市近自然绿地群落，创建野生动植物的适宜栖息地。 相似文献